WorldWideScience

Sample records for ponderosa pine stands

  1. Heavy thinning of ponderosa pine stands: An Arizona case study

    Science.gov (United States)

    Peter F. Ffolliott; Jr. Baker; Gerald J. Gottfried

    2000-01-01

    Growth and structural changes in a mosaic of even-aged ponderosa pine (Pinus ponderosa) stands were studied for 25 years to determine the long-term impacts of a heavy thinning treatment to a basal-area level of 25 ft2/acre. Basal area and volume growth of these stands has increased since thinning and likely will continue to...

  2. Mountain pine beetle-killed trees as snags in Black Hills ponderosa pine stands

    Science.gov (United States)

    J. M. Schmid; S. A. Mata; W. C. Schaupp

    2009-01-01

    Mountain pine beetle-killed ponderosa pine trees in three stands of different stocking levels near Bear Mountain in the Black Hills National Forest were surveyed over a 5-year period to determine how long they persisted as unbroken snags. Rate of breakage varied during the first 5 years after MPB infestation: only one tree broke during the first 2 years in the three...

  3. Susceptibility of ponderosa pine, Pinus ponderosa (Dougl. Ex Laws.), to mountain pine beetle, Dendroctonus ponderosae Hopkins, attack in uneven-aged stands in the Black Hills of South Dakota and Wyoming USA

    Science.gov (United States)

    Jose F. Negron; Kurt Allen; Blaine Cook; John R. Withrow

    2008-01-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins can cause extensive tree mortality in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests in the Black Hills of South Dakota and Wyoming. Most studies that have examined stand susceptibility to mountain pine beetle have been conducted in even-aged stands. Land managers...

  4. Site classification of ponderosa pine stands under stocking control in California

    Science.gov (United States)

    Robert F. Powers; William W. Oliver

    1978-01-01

    Existing systems for estimating site index of ponderosa pine (Pinus ponderosa Laws.) do not apply well to California stands where stocking is controlled. A more suitable system has been developed using trends in natural height growth, derived from stem analysis of dominant trees in California. This site index system produces polymorphic patterns of...

  5. FINE ROOT TURNOVER IN PONDEROSA PINE STANDS OF DIFFERENT AGES: FIRST-YEAR RESULTS

    Science.gov (United States)

    Root minirhizotron tubs were installed in two ponderosa pine (Pinus ponderosa Laws.) Stands of different ages to examine patterns of root growth and death. The old-growth site (OS) consists of a mixture of old (>250 years) and young trees (ca.45 yrs)< and is located near clamp S...

  6. SEASONAL PATTERNS OF FINE ROOT PRODUCTION AND TURNOVER IN PONDEROSA PINE STANDS OF DIFFERENT AGES

    Science.gov (United States)

    Root minirhizotron tubes were installed in two ponderosa pine (Pinus ponderosa Laws.) stands around three different tree age classes (16, 45, and > 250 yr old) to examine root spatial distribution in relation to canopy size and tree distribution, and to determine if rates of fine...

  7. Effects of stand density on top height estimation for ponderosa pine

    Science.gov (United States)

    Martin Ritchie; Jianwei Zhang; Todd Hamilton

    2012-01-01

    Site index, estimated as a function of dominant-tree height and age, is often used as an expression of site quality. This expression is assumed to be effectively independent of stand density. Observation of dominant height at two different ponderosa pine levels-of-growing-stock studies revealed that top height stability with respect to stand density depends on the...

  8. Economics of replacing young-growth ponderosa pine stands . . . a case study

    Science.gov (United States)

    Dennis E. Teeguarden

    1968-01-01

    Compares the expected capital value growth of five ponderosa pine stands (70 to 80 years old) on the Challenge Experimental Forest, Yuba County, Calif., with the cost of delaying harvest (defined as sum of stock-holding and land-holding costs). Suggests that replacement of all five stands would be financially desirable under constant stumpage prices. Recommends...

  9. ROOT GROWTH AND TURNOVER IN DIFFERENT AGED PONDEROSA PINE STANDS IN OREGON, USA

    Science.gov (United States)

    The impacts of pollution and climate change on soil carbon dynamics are poorly understood, in part due to a lack of information regarding root production and turnover in natural ecosystems. In order to examine how root dynamics change with stand age in ponderosa pine forests (...

  10. Economics of thinning stagnated ponderosa pine sapling stands in the pine-grass areas of central Washington.

    Science.gov (United States)

    Robert W. Sassaman; James W. Barrett; Justin G. Smith

    1972-01-01

    Present net worth values earned by investments in precommercial thinning of stagnated ponderosa pine sapling stands are reported for three stocking levels. Thirteen timber management regimes are ranked by their returns from timber only, and 22 regimes are ranked according to their returns from timber and forage, with and without the allowable cut effect.

  11. Ponderosa pine ecosystems

    Science.gov (United States)

    Russell T. Graham; Theresa B. Jain

    2005-01-01

    Ponderosa pine is a wide-ranging conifer occurring throughout the United States, southern Canada, and northern Mexico. Since the 1800s, ponderosa pine forests have fueled the economies of the West. In western North America, ponderosa pine grows predominantly in the moist and dry forests. In the Black Hills of South Dakota and the southern portion of its range, the...

  12. Efficacy of verbenone for protecting ponderosa pine stands from western pine beetle (Coleoptera: Curculionidae: Scolytinae) attack in California.

    Science.gov (United States)

    Fettig, Christopher J; McKelvey, Stephen R; Borys, Robert R; Dabney, Christopher P; Hamud, Shakeeb M; Nelson, Lori J; Seybold, Steven J

    2009-10-01

    The western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae: Scolytinae), is a major cause of ponderosa pine, Pinus ponderosa Dougl. ex Laws., mortality in much of western North America. Currently, techniques for managing D. brevicomis infestations are limited. Verbenone (4,6,6-trimethylbicyclo [3.1.1] hept-3-en-2-one) is an antiaggregation pheromone of several Dendroctonus spp., including D. brevicomis, and it has been registered as a biopesticide for control of mountain pine beetle, Dendroctonus ponderosae Hopkins, and southern pine beetle, Dendroctonus frontalis Zimmermann. We evaluated the efficacy of a 5-g verbenone pouch [82%-(-); 50 mg/d] applied at 125 Ulha for protecting P. ponderosa stands (2 ha) from D. brevicomis attack over a 3-yr period. No significant differences in levels of D. brevicomis-caused tree mortality or the percentage of unsuccessfully attacked trees were found between verbenone-treated and untreated plots during each year or cumulatively over the 3-yr period. Laboratory analyses of release rates and chemical composition of volatiles emanating from verbenone pouches after field exposure found no deterioration of the active ingredient or physical malfunction of the release device. The mean release rate of pouches from all locations and exposure periods was 44.5 mg/d. In a trapping bioassay, the range of inhibition of the 5-g verbenone pouch was determined to be statistically constant 2 m from the release device. We discuss the implications of these and other results to the development of verbenone as a semiochemical-based tool for management of D. brevicomis infestations in P. ponderosa stands.

  13. Stand-replacing wildfires increase nitrification for decades in southwestern ponderosa pine forests.

    Science.gov (United States)

    Kurth, Valerie J; Hart, Stephen C; Ross, Christopher S; Kaye, Jason P; Fulé, Peter Z

    2014-05-01

    Stand-replacing wildfires are a novel disturbance within ponderosa pine (Pinus ponderosa) forests of the southwestern United States, and they can convert forests to grasslands or shrublands for decades. While most research shows that soil inorganic N pools and fluxes return to pre-fire levels within a few years, we wondered if vegetation conversion (ponderosa pine to bunchgrass) following stand-replacing fires might be accompanied by a long-term shift in N cycling processes. Using a 34-year stand-replacing wildfire chronosequence with paired, adjacent unburned patches, we examined the long-term dynamics of net and gross nitrogen (N) transformations. We hypothesized that N availability in burned patches would become more similar to those in unburned patches over time after fire as these areas become re-vegetated. Burned patches had higher net and gross nitrification rates than unburned patches (P < 0.01 for both), and nitrification accounted for a greater proportion of N mineralization in burned patches for both net (P < 0.01) and gross (P < 0.04) N transformation measurements. However, trends with time-after-fire were not observed for any other variables. Our findings contrast with previous work, which suggested that high nitrification rates are a short-term response to disturbance. Furthermore, high nitrification rates at our site were not simply correlated with the presence of herbaceous vegetation. Instead, we suggest that stand-replacing wildfire triggers a shift in N cycling that is maintained for at least three decades by various factors, including a shift from a woody to an herbaceous ecosystem and the presence of fire-deposited charcoal.

  14. Stand Characteristics and Downed Woody Debris Accumulations Associated with a Mountain Pine Beetle (Dendroctonus ponderosae Hopkins) Outbreak in Colorado

    OpenAIRE

    Klutsch, Jennifer G; Negron, Jose F; Costello, Sheryl L; Rhoades, Charles C; West, Daniel R; Popp, John; Caissie, Rick

    2009-01-01

    Lodgepole pine (Pinus contorta Dougl. ex Loud.)-dominated ecosystems in north-central Colorado are undergoing rapid and drastic changes associated with overstory tree mortality from a current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak. To characterize stand characteristics and downed woody debris loads during the first 7 years of the outbreak, 221 plots (0.02 ha) were randomly established in infested and uninfested stands distributed across the Arapaho National Forest, ...

  15. Response of ponderosa pine stands to pre-commercial thinning on Nez Perce and Spokane Tribal forests in the Inland Northwest, USA

    Science.gov (United States)

    Dennis E. Ferguson; John C. Byrne; William R. Wykoff; Brian Kummet; Ted Hensold

    2011-01-01

    Stands of dense, natural ponderosa pine (Pinus ponderosa var. ponderosa) regeneration were operationally, precommercially thinned at seven sites - four on Nez Perce Tribal lands in northern Idaho and three on Spokane Tribal lands in eastern Washington. Five spacing treatments were studied - control (no thinning), 5x5 ft, 7x7 ft, 10x10 ft, and 14x14 ft. Sample trees...

  16. Simulating historical disturbance regimes and stand structures in old-forest ponderosa pine/Douglas-fir forests

    Science.gov (United States)

    Mike Hillis; Vick Applegate; Steve Slaughter; Michael G. Harrington; Helen Smith

    2001-01-01

    Forest Service land managers, with the collaborative assistance from research, applied a disturbance based restoration strategy to rehabilitate a greatly-altered, high risk Northern Rocky Mountain old-forest ponderosa pine-Douglas-fir stand. Age-class structure and fire history for the site have been documented in two research papers (Arno and others 1995, 1997)....

  17. Brush competition retards early stand development of planted ponderosa pine: update on a 24-year study

    Science.gov (United States)

    William W. Oliver

    1990-01-01

    Growth of ponderosa pine (Pinus ponderosa) was monitored for 24 years after planting at five different square spacings (6, 9. 12, 15, and 18 ft) in the presence or absence of competing brush on the westside Sierra Nevada. Spacing strongly influenced both mean dbh and basal area/ac. In plots maintained free of brush, diameters ranged from 5.1 in. at the 6-ft spacing to...

  18. Tree Regeneration Spatial Patterns in Ponderosa Pine Forests Following Stand-Replacing Fire: Influence of Topography and Neighbors

    Directory of Open Access Journals (Sweden)

    Justin P. Ziegler

    2017-10-01

    Full Text Available Shifting fire regimes alter forest structure assembly in ponderosa pine forests and may produce structural heterogeneity following stand-replacing fire due, in part, to fine-scale variability in growing environments. We mapped tree regeneration in eighteen plots 11 to 15 years after stand-replacing fire in Colorado and South Dakota, USA. We used point pattern analyses to examine the spatial pattern of tree locations and heights as well as the influence of tree interactions and topography on tree patterns. In these sparse, early-seral forests, we found that all species were spatially aggregated, partly attributable to the influence of (1 aspect and slope on conifers; (2 topographic position on quaking aspen; and (3 interspecific attraction between ponderosa pine and other species. Specifically, tree interactions were related to finer-scale patterns whereas topographic effects influenced coarse-scale patterns. Spatial structures of heights revealed conspecific size hierarchies with taller trees in denser neighborhoods. Topography and heterospecific tree interactions had nominal effect on tree height spatial structure. Our results demonstrate how stand-replacing fires create heterogeneous forest structures and suggest that scale-dependent, and often facilitatory, rather than competitive, processes act on regenerating trees. These early-seral processes will establish potential pathways of stand development, affecting future forest dynamics and management options.

  19. Sex Pheromone of Conophthorus ponderosae (Coleoptera: Scolytidae) in a Coastal Stand of Western White Pine (Pinaceae)

    Science.gov (United States)

    Daniel R. Miller; Harold D. Pierce; Peter de Groot; Nicole Jeans-Williams; Robb Bennett; John H. Borden

    2000-01-01

    An isolated stand of western white pine, Pinus monticola Dougl. ex D. Don, on Texada Island (49°40'N, 124°10'W), British Columbia, is extremely valuable as a seed-production area for progeny resistant to white pine blister rust, Cronartium ribicola J.C. Fisch. (Cronartiaceae). During the past 5 years, cone beetles, ...

  20. Recovery of ponderosa pine ecosystem carbon and water fluxes from thinning and stand-replacing fire.

    Science.gov (United States)

    Dore, Sabina; Montes-Helu, Mario; Hart, Stephen C; Hungate, Bruce A; Koch, George W; Moon, John B; Finkral, Alex J; Kolb, Thomas E

    2012-10-01

    Carbon uptake by forests is a major sink in the global carbon cycle, helping buffer the rising concentration of CO 2 in the atmosphere, yet the potential for future carbon uptake by forests is uncertain. Climate warming and drought can reduce forest carbon uptake by reducing photosynthesis, increasing respiration, and by increasing the frequency and intensity of wildfires, leading to large releases of stored carbon. Five years of eddy covariance measurements in a ponderosa pine (Pinus ponderosa)-dominated ecosystem in northern Arizona showed that an intense wildfire that converted forest into sparse grassland shifted site carbon balance from sink to source for at least 15 years after burning. In contrast, recovery of carbon sink strength after thinning, a management practice used to reduce the likelihood of intense wildfires, was rapid. Comparisons between an undisturbed-control site and an experimentally thinned site showed that thinning reduced carbon sink strength only for the first two posttreatment years. In the third and fourth posttreatment years, annual carbon sink strength of the thinned site was higher than the undisturbed site because thinning reduced aridity and drought limitation to carbon uptake. As a result, annual maximum gross primary production occurred when temperature was 3 °C higher at the thinned site compared with the undisturbed site. The severe fire consistently reduced annual evapotranspiration (range of 12-30%), whereas effects of thinning were smaller and transient, and could not be detected in the fourth year after thinning. Our results show large and persistent effects of intense fire and minor and short-lived effects of thinning on southwestern ponderosa pine ecosystem carbon and water exchanges. © 2012 Blackwell Publishing Ltd.

  1. Climate-influenced ponderosa pine (Pinus ponderosa) seed masting trends in western Montana, USA

    OpenAIRE

    Keyes, Christopher R.; Gonzalez, Ruben Manso

    2015-01-01

    Aim of study: The aim of this study was to analyze 10-year records of ponderosa pine (Pinus ponderosa) seed production, in order to confirm synchronic seed production and to evaluate cyclical masting trends, masting depletion effect, and climate-masting relationships. Area of study: The study area was located in a P. ponderosa stand in the northern Rocky Mountains (western Montana, USA). Material and methods: The study was conducted in one stand that had been subjected to a silvicul...

  2. Silvicultural recommendations for the management of ponderosa pine forest

    Science.gov (United States)

    Martin Alfonso Mendoza Briseno; Mary Ann Fajvan; Juan Manuel Chacon Sotelo; Alejandro Velazquez Martinez; Antonio Quinonez. Silva

    2014-01-01

    Ponderosa pines are the most important timber producing species in Mexico, and they also represent a major portion of the Usa and Canada timber production. These pines form near pure stands with simple and stable stand structure. They suffer only occasional disturbances, and they sustain a limited capacity to hold biodiversity and other senvironmental services. The...

  3. Conserving genetic diversity in Ponderosa Pine ecosystem restoration

    Science.gov (United States)

    L.E. DeWald

    2017-01-01

    Restoration treatments in the ponderosa pine (Pinus ponderosa P. & C. Lawson) ecosystems of the southwestern United States often include removing over 80 percent of post-EuroAmerican settlement-aged trees to create healthier forest structural conditions. These types of stand density reductions can have negative effects on genetic diversity. Allozyme analyses...

  4. Efficacy of "Verbenone Plus" for protecting ponderosa pine trees and stands from Dendroctonus brevicomis (Coleoptera: Curculionidae) attack in British Columbia and California.

    Science.gov (United States)

    Fettig, Christopher J; McKelvey, Stephen R; Dabney, Christopher P; Huber, Dezene P W; Lait, Cameron G; Fowler, Donald L; Borden, John H

    2012-10-01

    The western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae, Scolytinae), is a major cause of ponderosa pine, Pinus ponderosa Douglas ex Lawson, mortality in much of western North America. We review several years of research that led to the identification of Verbenone Plus, a novel four-component semiochemcial blend [acetophenone, (E)-2-hexen-1-ol + (Z)-2-hexen-1-ol, and (-)-verbenone] that inhibits the response of D. brevicomis to attractant-baited traps, and examine the efficacy of Verbenone Plus for protecting individual trees and forest stands from D. brevicomis infestations in British Columbia and California. In all experiments, semiochemicals were stapled around the bole of treated trees at approximately equal to 2 m in height. (-)-Verbenone alone had no effect on the density of total attacks and successful attacks by D. brevicomis on attractant-baited P. ponderosa, but significantly increased the percentage of pitchouts (unsuccessful D. brevicomis attacks). Verbenone Plus significantly reduced the density of D. brevicomis total attacks and D. brevicomis successful attacks on individual trees. A significantly higher percentage of pitchouts occurred on Verbenone Plus-treated trees. The application of Verbenone Plus to attractant-baited P. ponderosa significantly reduced levels of tree mortality. In stand protection studies, Verbenone Plus significantly reduced the percentage of trees mass attacked by D. brevicomis in one study, but in a second study no significant treatment effect was observed. Future research should concentrate on determining optimal release rates and spacings of release devices in stand protection studies, and expansion of Verbenone Plus into other systems where verbenone alone has not provided adequate levels of tree protection.

  5. Efficacy of “Verbenone Plus” for protecting ponderosa pine trees and stands from Dendroctonus brevicomis (Coleoptera: Curculionidae) attack in British Columbia and California

    Science.gov (United States)

    Christopher J. Fettig; Stephen R. McKelvey; Christopher P. Dabney; Dezene P.W. Huber; Cameron C. Lait; Donald L Fowler; John H. Borden

    2012-01-01

    The western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae, Scolytinae), is a major cause of ponderosa pine, Pinus ponderosa Douglas ex Lawson, mortality in much of western North America. We review several years of research that led to the identification of Verbenone Plus, a novel four-component...

  6. Spread of dwarf mistletoe from discrete seed sources into young stands of ponderosa and Jeffrey pines

    Science.gov (United States)

    J. R. Parmeter Jr.

    1972-01-01

    The maximum distance of spread of dwarf mistletoes from isolated overstory pines into surrounding reproduction averages 120 feet. The rate of infection in young trees declined as distance from the seed source increased and was generally greatest in the direction of prevailing winds. This pattern of infection was similar to the previously reported pattern of seed...

  7. Season of prescribed burn in ponderosa pine forests in eastern Oregon: impact on pine mortality.

    Science.gov (United States)

    Walter G. Thies; Douglas J. Westlind; Mark. Loewen

    2005-01-01

    A study of the effects of season of prescribed burn on tree mortality was established in mixed-age ponderosa pine (Pinus ponderosa Dougl. ex Laws.) at the south end of the Blue Mountains near Burns, Oregon. Each of six previously thinned stands was subdivided into three experimental units and one of three treatments was randomly assigned to each:...

  8. PATTERNS OF ROOT GROWTH, TURNOVER, AND DISTRIBUTION IN DIFFERENT AGED PONDEROSA PINE STANDS

    Science.gov (United States)

    The objectives of this study are to examine the spatial distribution of roots in relation to canopy size and tree distribution, and to determine if rates of fine root production and turnover are similar in the different aged stands. During the fall of 1998, 54 clear plexiglass t...

  9. Should ponderosa pine be planted on lodgepole pine sites?

    Science.gov (United States)

    P.H. Cochran

    1984-01-01

    Repeated radiation frosts caused no apparent harm to the majority of lodgepole pine (Pinus contorta Dougl.) seedlings planted on a pumice flat in south-central Oregon. For most but not all of the ponderosa pine (Pinus ponderosa Dougl.) seedlings planted with the lodgepole pine, however, damage from radiation frost resulted in...

  10. Diprionidae sawflies on lodgepole and ponderosa pines

    Science.gov (United States)

    Eight species of Diprionidae feed on lodgepole pine (Pinus contorta) and ponderosa pine (P. ponderosa) in western United States: Neodiprion burkei Middleton, N. annulus contortae Ross, N. autumnalis Smith, N. fulviceps (Cresson), N. gillettei (Rohwer), N. mundus Rohwer, N. ventralis Ross, and Zadi...

  11. How resilient are southwestern ponderosa pine forests after crown fires?

    OpenAIRE

    Savage, M; Mast, J N

    2005-01-01

    The exclusion of low-severity surface fire from ponderosa pine (Pinus ponderosa P. & C. Lawson) forests of the Southwest has changed ecosystem structure and function such that severe crown fires are increasingly causing extensive stand mortality. This altered fire regime has resulted from the intersection of natural drought cycles with human activities that have suppressed natural fires for over a century. What is the trajectory of forest recovery after such fires? This study explores the reg...

  12. Do Pine Trees in Aspen Stands Increase Bird Diversity

    OpenAIRE

    Rumble, Mark A; Mills, Todd R; Dystra, Brian L; Flake, Lester D

    2001-01-01

    In the Black Hills of South Dakota, quaking aspen (Populus tremuloides) is being replaced by conifers through fire suppression and successional processes. Al- though the Black Hills National forest is removing conifers (primarily ponderosa pine [Pinus ponderosa])toincreasetheaspencommunitiesinsomemixedstands,ForestPlan guidelines allow four conifers per hectare to remain to increase diversity in the remaining aspen stand. We compared bird species richness in pure ponderosa pine, mixed stands ...

  13. Black stain root disease studies on ponderosa pine parameters and disturbance treatments affecting infection and mortality

    Science.gov (United States)

    W.J. Otrosina; J.T. Kliejunas; S. Smith; D.R. Cluck; S.S. Sung; C.D. Cook

    2007-01-01

    Black stain root disease of ponderosa pine (Pinus ponderosa Doug. Ex Laws.), caused by Leptographium wageneri var. ponderosum (Harrington & Cobb) Harrington & Cobb, is increasing on many eastside Sierra Nevada pine stands in northeastern California. The disease is spread from tree to tree via root...

  14. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Directory of Open Access Journals (Sweden)

    Jens T Stevens

    Full Text Available Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA program reflects the timing of historical high-severity (i.e. stand-replacing fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1 the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2 recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  15. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Science.gov (United States)

    Stevens, Jens T; Safford, Hugh D; North, Malcolm P; Fried, Jeremy S; Gray, Andrew N; Brown, Peter M; Dolanc, Christopher R; Dobrowski, Solomon Z; Falk, Donald A; Farris, Calvin A; Franklin, Jerry F; Fulé, Peter Z; Hagmann, R Keala; Knapp, Eric E; Miller, Jay D; Smith, Douglas F; Swetnam, Thomas W; Taylor, Alan H

    Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA) program reflects the timing of historical high-severity (i.e. stand-replacing) fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1) the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2) recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  16. Wood and understory production under a range of ponderosa pine stocking levels, Black Hills, South Dakota

    Science.gov (United States)

    Daniel W. Uresk; Carleton B. Edminster; Kieth E. Severson

    2000-01-01

    Stemwood and understory production (kg ha-1) were estimated during 3 nonconsecutive years on 5 growing stock levels of ponderosa pine including clearcuts and unthinned stands. Stemwood production was consistently greater at mid- and higher pine stocking levels, and understory production was greater in stands with less pine; however, there were no...

  17. Spacing and shrub competition influence 20-year development of planted ponderosa pine

    Science.gov (United States)

    William W. Oliver

    1990-01-01

    Growth and stand development of ponderosa pine (Pinus ponderosa) were monitored for 20 years after planting at five different square spacings (6, 9, 12, 15, and 18 ft) in the presence or absence of competing shrubs on the westside Sierra Nevada. Mean tree size was positively correlated and stand values negatively correlated with spacing in the...

  18. Responses of cavity-nesting birds to stand-replacement fire and salvage logging in ponderosa pine/Douglas-fir forests of southwestern Idaho

    Science.gov (United States)

    Victoria A. Saab; Jonathan G. Dudley

    1998-01-01

    From 1994 to 1996, researchers monitored 695 nests of nine cavity-nesting bird species and measured vegetation at nest sites and at 90 randomly located sites in burned ponderosa pine forests of southwestern Idaho. Site treatments included two types of salvage logging, and unlogged controls. All bird species selected nest sites with higher tree densities, larger...

  19. Mountain Pine Beetle Dynamics and Reproductive Success in Post-Fire Lodgepole and Ponderosa Pine Forests in Northeastern Utah.

    Directory of Open Access Journals (Sweden)

    Andrew P Lerch

    Full Text Available Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae, but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug. and 599 ponderosa (Pinus ponderosa Doug. ex Law pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.

  20. Mountain Pine Beetle Dynamics and Reproductive Success in Post-Fire Lodgepole and Ponderosa Pine Forests in Northeastern Utah.

    Science.gov (United States)

    Lerch, Andrew P; Pfammatter, Jesse A; Bentz, Barbara J; Raffa, Kenneth F

    2016-01-01

    Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae), but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins) is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug.) and 599 ponderosa (Pinus ponderosa Doug. ex Law) pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.

  1. Resilience of ponderosa and lodgepole pine forests to mountain pine beetle disturbance and limited regeneration

    Science.gov (United States)

    Briggs, Jenny S.; Hawbaker, Todd J.; Vandendriesche, Don

    2015-01-01

    After causing widespread mortality in lodgepole pine forests in North America, the mountain pine beetle (MPB) has recently also affected ponderosa pine, an alternate host species that may have different levels of resilience to this disturbance. We collected field data in ponderosa pine- and lodgepole pine-dominated forests attacked by MPB in Colorado and then simulated stand growth over 200 years using the Forest Vegetation Simulator. We compared scenarios of no disturbance with scenarios of MPB-caused mortality, both with and without regeneration. Results indicated that basal area and tree density recovered to predisturbance levels relatively rapidly (within 1‐8 decades) in both forest types. However, convergence of the disturbed conditions with simulated undisturbed conditions took longer (12‐20+ decades) and was delayed by the absence of regeneration. In MPB-affected ponderosa pine forests without regeneration, basal area did not converge with undisturbed conditions within 200 years, implying lower resilience in this ecosystem. Surface fuels accumulated rapidly in both forest types after MPB-induced mortality, remaining high for 3‐6 decades in simulations. Our results suggest that future patterns of succession, regeneration, fuel loading, climate, and disturbance interactions over long time periods should be considered in management strategies addressing MPB effects in either forest type, but particularly in ponderosa pine.

  2. Growth models for ponderosa pine: I. Yield of unthinned plantations in northern California.

    Science.gov (United States)

    William W. Oliver; Robert F. Powers

    1978-01-01

    Yields for high-survival, unthinned ponderosa pine (Pinus ponderosa Laws.) plantations in northern California are estimated. Stems of 367 trees in 12 plantations were analyzed to produce a growth model simulating stand yields. Diameter, basal area, and net cubic volume yields by Site Indices50 40 through 120 are tabulated for...

  3. Ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone.

    Science.gov (United States)

    Garcia, Maria O; Smith, Jane E; Luoma, Daniel L; Jones, Melanie D

    2016-05-01

    Forest ecosystems of the Pacific Northwest of the USA are changing as a result of climate change. Specifically, rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. Simultaneously, flux in environmental conditions within the historic P. contorta range may facilitate the encroachment of P. ponderosa into P. contorta territory. Furthermore, successful pine species migration may be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study were to establish a foundational knowledge of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest, OR, USA, and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa cores. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa were dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa cores. There was no significant difference in the species composition of EMF communities of P. ponderosa and P. contorta. Ordination analysis of P. ponderosa soils suggested that soil pH, plant-available phosphorus (Bray), total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH4), and nitrate (NO3) are driving EMF community composition in P. ponderosa stands. We found a significant linear relationship between EMF species richness and mineralizable N. In conclusion, P. ponderosa and P. contorta, within the Deschutes National Forest, share the same dominant EMF species, which implies that P. ponderosa may be able to successfully establish

  4. CARBON ISOTOPE DISCRIMINATION AND GROWTH RESPONSE OF OLD PINUS PONDEROSA TREES TO STAND DENSITY REDUCTIONS

    Science.gov (United States)

    Stand density reductions have been proposed as a method by which old-growth ponderosa pine (Pinus ponderosa) forests of North America can be converted back to pre-1900 conditions, thereby reducing the danger of catastrophic forest fires and insect attacks while increasing product...

  5. A ponderosa pine-lodgepole pine spacing study in central Oregon: results after 20 years.

    Science.gov (United States)

    K.W. Seidel

    1989-01-01

    The growth response after 20 years from an initial spacing study established in a ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and lodgepole pine (Pinus contorta Dougl. ex Loud.) plantation was measured in central Oregon. The study was designed to compare the growth rates of pure ponderosa pine, pure lodgepole pine, and a...

  6. Inhibiting effect of ponderosa pine seed trees on seedling growth

    Science.gov (United States)

    Philip M. McDonald

    1976-01-01

    Ponderosa pine seed trees, numbering 4, 8, and 12 per acre, were left standing for 9 years after harvest cutting on the Challenge Experimental Forest, Calif. Seedling heights were measured at ages 5, 9, and 14, and for all ages were poorest if within 20 feet of a seed tree. Seedlings 20 feet or less from a seed tree at the ages given lost the equivalent in years of...

  7. Insects associated with ponderosa pine in Colorado

    Science.gov (United States)

    Robert E. Stevens; J. Wayne Brewer; David A. Leatherman

    1980-01-01

    Ponderosa pine serves as a host for a wide variety of insects. Many of these, including all the particularly destructive ones in Colorado, are discussed in this report. Included are a key to the major insect groups, an annotated list of the major groups, a glossary, and a list of references.

  8. Host Defense Mechanisms against Bark Beetle Attack Differ between Ponderosa and Lodgepole Pines

    Directory of Open Access Journals (Sweden)

    Daniel R. West

    2016-10-01

    Full Text Available Conifer defenses against bark beetle attack include, but are not limited to, quantitative and qualitative defenses produced prior to attack. Our objective was to assess host defenses of lodgepole pine and ponderosa pine from ecotone stands. These stands provide a transition of host species for mountain pine beetle (Dendroctonus ponderosae; MPB. We asked two questions: (1 do the preformed quantitative host defenses (amount of resin and (2 the preformed qualitative host defenses (monoterpene constituents differ between lodgepole and ponderosa pines. We collected oleoresins at three locations in the Southern Rocky Mountains from 56 pairs of the pine species of similar size and growing conditions. The amount of preformed-ponderosa pine oleoresins exuded in 24 h (mg was almost four times that of lodgepole pine. Total qualitative preformed monoterpenes did not differ between the two hosts, though we found differences in all but three monoterpenes. No differences were detected in α-pinene, γ-terpinene, and bornyl acetate. We found greater concentrations of limonene, β-phellandrene, and cymene in lodgepole pines, whereas β-pinene, 3-carene, myrcene, and terpinolene were greater in ponderosa pine. Although we found differences both in quantitative and qualitative preformed oleoresin defenses, the ecological relevance of these differences to bark beetle susceptibility have not been fully tested.

  9. Unthinned slow-growing ponderosa pine (Pinus ponderosa) trees contain muted isotopic signals in tree rings as compared to thinned trees

    Science.gov (United States)

    We analysed the oxygen isotopic values of wood (δ18Ow) of 12 ponderosa pine (Pinus ponderosa) trees from control, moderately, and heavily thinned stands and compared them with existing wood-based estimates of carbon isotope discrimination (∆13C), basal area increment (BAI), and g...

  10. Lumber recovery from small-diameter ponderosa pine from Flagstaff, Arizona

    Science.gov (United States)

    Eini C. Lowell; David W. Green

    2001-01-01

    Thousands of acres of densely stocked ponderosa pine forests surround Flagstaff, AZ. These stands are at high risk of fire, insect, and disease outbreak. Stand density management activity can be expensive, but product recovery from the thinned material could help defray removal costs. This project evaluated the yield and economic return of lumber recovered from small-...

  11. Prescribed burning in the interior ponderosa pine type of northeastern California . . . a preliminary study

    Science.gov (United States)

    Donald T. Gordon

    1967-01-01

    Three prescribed burns, made in 1959-62, in the interior ponderosa pine type of northeastern California are described in terms of meteorological factors, fire behavior, and effects of burning. Results were generally unsatisfactory. Factors that limit the usefulness of prescribed burning for reducing fuel hazard or for thinning in young-growth stands include stand...

  12. Late Holocene expansion of Ponderosa pine (Pinus ponderosa) in the Central Rocky Mountains, USA

    Science.gov (United States)

    Norris, Jodi R; Betancourt, Julio L.; Jackson, Stephen T.

    2016-01-01

    "Aim: Ponderosa pine (Pinus ponderosa) experienced one of the most extensive and rapid post-glacial plant migrations in western North America. We used plant macrofossils from woodrat (Neotoma) middens to reconstruct its spread in the Central Rocky Mountains, identify other vegetation changes coinciding with P. ponderosa expansion at the same sites, and relate P. ponderosa migrational history to both its modern phylogeography and to a parallel expansion by Utah juniper (Juniperus osteosperma).

  13. Large-scale thinning, ponderosa pine, and mountain pine beetle in the Black Hills, USA

    Science.gov (United States)

    Jose F. Negron; Kurt K. Allen; Angie Ambourn; Blaine Cook; Kenneth Marchand

    2017-01-01

    Mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB), can cause extensive ponderosa pine (Pinus ponderosa Dougl. ex Laws.) mortality in the Black Hills of South Dakota and Wyoming, USA. Lower tree densities have been associated with reduced MPB-caused tree mortality, but few studies have reported on large-scale thinning and most data come from small plots that...

  14. Dose-dependent pheromone responses of mountain pine beetle in stands of lodgepole pine

    Science.gov (United States)

    Daniel R. Miller; B. Staffan Lindgren; John H. Borden

    2005-01-01

    We conducted seven behavioral choice tests with Lindgren multiple-funnel traps in stands of mature lodgepole pine in British Columbia, from 1988 to 1994, to determine the dosedependent responses of the mountain pine beetle, Dendroctonus ponderosae Hopkins, to its pheromones. Amultifunctional dose-dependent response was exhibited by D. ...

  15. Effect of prescribed burning on mortality of resettlement ponderosa pines in Grand Canyon National Park

    Science.gov (United States)

    G. Alan Kaufmann; W. Wallace Covington

    2001-01-01

    Ponderosa pine (Pinus ponderosa) trees established before Euro-American settlement are becoming rare on the landscape. Prescribed fire is the prime tool used to restore ponderosa pine ecosystems, but can cause high mortality in presettlement ponderosa pines. This study uses retrospective techniques to estimate mortality from prescribed burns within Grand Canyon...

  16. Predictions of fire behavior and resistance to control: for use with photo series for the ponderosa pine type, ponderosa pine and associated species type, and lodgepole pine type.

    Science.gov (United States)

    Franklin R. Ward; David V. Sandberg

    1981-01-01

    This publication presents tables on the behavior of fire and the resistance of fuels to control. The information is to be used with the publication, "Photo Series for Quantifying Forest Residues in the Ponderosa Pine Type, Ponderosa Pine and Associated Species Type, Lodgepole Pine Type" (Maxwell, Wayne G.; Ward, Franklin R. 1976. Gen. Tech. Rep. PNW-GTR-052....

  17. CARBON STORAGE AND FLUXES IN PONDEROSA PINE AT DIFFERENT SUCCESSIONAL STAGES

    Science.gov (United States)

    We compared carbon storage and fluxes in young and old ponderosa pine stands in Oregon, including plant and soil storage, net primary productivity, respiration fluxes, and eddy flux estimates of net ecosystem exchange. The young site (Y site) was previously an old-growth pondero...

  18. Response of dwarf mistletoe-infested ponderosa pine to thinning: 2. Dwarf mistletoe propagation.

    Science.gov (United States)

    Lewis F. Roth; James W. Barrett

    1985-01-01

    Propagation of dwarf mistletoe in ponderosa pine saplings is little influenced by thinning overly dense stands to 250 trees per acre. Numerous plants that appear soon after thinning develop from formerly latent plants in the suppressed under-story. Subsequently, dwarf mistletoe propagates nearly as fast as tree crowns enlarge but the rate differs widely among trees....

  19. Ponderosa pine growth response to soil strength in the volcanic ash soils of central Oregon.

    Science.gov (United States)

    R.T. Parker; D.A. Maguire; D.D. Marshall; P. Cochran

    2007-01-01

    Mechanical harvesting and associated logging activities have the capacity to compact soil across large portions of harvest units. Two thinning treatments (felled only versus felled and skidded) in 70- to 80-year-old ponderosa pine stands were replicated at three sites with volcanic soils in central Oregon. Growth in diameter, height, and volume of residual trees were...

  20. Dynamic programming for optimization of timber production and grazing in ponderosa pine

    Science.gov (United States)

    Kurt H. Riitters; J. Douglas Brodie; David W. Hann

    1982-01-01

    Dynamic programming procedures are presented for optimizing thinning and rotation of even-aged ponderosa pine by using the four descriptors: age, basal area, number of trees, and time since thinning. Because both timber yield and grazing yield are functions of stand density, the two outputs-forage and timber-can both be optimized. The soil expectation values for single...

  1. Climate-influenced ponderosa pine (Pinus ponderosa seed masting trends in western Montana, USA

    Directory of Open Access Journals (Sweden)

    Christopher R. Keyes

    2015-04-01

    Full Text Available Aim of study: The aim of this study was to analyze 10-year records of ponderosa pine (Pinus ponderosa seed production, in order to confirm synchronic seed production and to evaluate cyclical masting trends, masting depletion effect, and climate-masting relationships. Area of study: The study area was located in a P. ponderosa stand in the northern Rocky Mountains (western Montana, USA. Material and methods: The study was conducted in one stand that had been subjected to a silvicultural study of uneven-aged management techniques that was carried out in 1984, and which resulted in three separate units consisting of one control, one cut/no-burn treatment, and one cut/burn treatment. Seeds were collected during the 10 years following treatment in 15 traps systematically deployed within each of the stand’s three units. The total numbers of seeds collected in each unit were plotted over time to analyze crop synchrony, with Spearman rank correlation coefficient used to test for masting cycles and crop depletion after a mast year. Meteorological records over the period 1983-1994 were related to the occurrence of a mast event (defined as crops exceeding 50,000 viable seeds/ha. Main results: The seed production pattern was non-cyclical, synchronous, and independent of silvicultural treatment history. A mast-depletion effect was evident but was not statistically significant. Mast events seem to be promoted by the occurrence of optimum mean temperatures at the beginning of spring during both the first (11 °C and second (9 °C years of cone maturation. The probability of a mast year was also affected by summer temperature (number of late frost days; negative effect and precipitation amount (positive effect. All these factors would seemingly explain the observed synchronous pattern in cone production. Research highlights: The non-cyclical trend of ponderosa pine seed mast years is influenced by specific climate determinants. Fluctuations in mean early

  2. Fungal endophytes in woody roots of Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa)

    Science.gov (United States)

    J. A. Hoff; Ned B. Klopfenstein; Geral I. McDonald; Jonalea R. Tonn; Mee-Sook Kim; Paul J. Zambino; Paul F. Hessburg; J. D. Rodgers; T. L. Peever; L. M. Carris

    2004-01-01

    The fungal community inhabiting large woody roots of healthy conifers has not been well documented. To provide more information about such communities, a survey was conducted using increment cores from the woody roots of symptomless Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa) growing in dry forests...

  3. Nuclear genetic variation across the range of ponderosa pine (Pinus ponderosa): Phylogeographic, taxonomic and conservation implications

    Science.gov (United States)

    Kevin M. Potter; Valerie D. Hipkins; Mary F. Mahalovich; Robert E. Means

    2015-01-01

    Ponderosa pine (Pinus ponderosa) is among the most broadly distributed conifer species of western North America, where it possesses considerable ecological, esthetic, and commercial value. It exhibits complicated patterns of morphological and genetic variation, suggesting that it may be in the process of differentiating into distinct regional...

  4. Dwarf Mistletoe of Ponderosa Pine in the Southwest (FIDL)

    Science.gov (United States)

    Paul C. Lightle; Melvyn J. Weiss

    1974-01-01

    Southwestern dwarf mistletoe (Arceuthobuim vaginatum subsp. cryptopodum) occurs essentially throughout the range of ponderosa pine (Pinus ponderosa var. scopulorum) from northern Mexico through western Texas, Arizona, and New Mexico into Colorado and central Utah. In Arizona and New Mexico it is present on more than one-third of the commercial forest acreage and is...

  5. Silvicultural systems and cutting methods for ponderosa pine forests in the Front Range of the central Rocky Mountains

    Science.gov (United States)

    Robert R. Alexander

    1986-01-01

    Guidelines are provided to help forest managers and silviculturists develop even- and/or uneven-aged cutting practices needed to convert old-growth and mixed ponderosa pine forests in the Front Range into managed stands for a variety of resource needs. Guidelines consider stand conditions, and insect and disease susceptibility. Cutting practices are designed to...

  6. Severity of a mountain pine beetle outbreak across a range of stand conditions in Fraser Experimental Forest, Colorado, United States

    Science.gov (United States)

    Anthony G. Vorster; Paul H. Evangelista; Thomas J. Stohlgren; Sunil Kumar; Charles C. Rhoades; Robert M. Hubbard; Antony S. Cheng; Kelly Elder

    2017-01-01

    The recent mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks had unprecedented effects on lodgepole pine (Pinus contorta var. latifolia) in western North America. We used data from 165 forest inventory plots to analyze stand conditions that regulate lodgepole pine mortality across a wide range of stand structure and species composition at the Fraser...

  7. Tree regeneration and future stand development after bark beetle infestation and harvesting in Colorado lodgepole pine stands

    Science.gov (United States)

    Byron J. Collins; Charles C. Rhoades; Robert M. Hubbard; Michael A. Battaglia

    2011-01-01

    In the southern Rocky Mountains, current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks and associated harvesting have set millions of hectares of lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forest onto new stand development trajectories. Information about immediate, post-disturbance tree regeneration will provide insight on...

  8. User guide for HCR Estimator 2.0: software to calculate cost and revenue thresholds for harvesting small-diameter ponderosa pine.

    Science.gov (United States)

    Dennis R. Becker; Debra Larson; Eini C. Lowell; Robert B. Rummer

    2008-01-01

    The HCR (Harvest Cost-Revenue) Estimator is engineering and financial analysis software used to evaluate stand-level financial thresholds for harvesting small-diameter ponderosa pine (Pinus ponderosa Dougl. ex Laws.) in the Southwest United States. The Windows-based program helps contractors and planners to identify costs associated with tree...

  9. Mountain pine beetle attack associated with low levels of 4-allylanisole in ponderosa pine.

    Science.gov (United States)

    Emerick, Jay J; Snyder, Aaron I; Bower, Nathan W; Snyder, Marc A

    2008-08-01

    Mountain pine beetle (Dendroctonus ponderosae) is the most important insect pest in southern Rocky Mountain ponderosa pine (Pinus ponderosa) forests. Tree mortality is hastened by the various fungal pathogens that are symbiotic with the beetles. The phenylpropanoid 4-allylanisole is an antifungal and semiochemical for some pine beetle species. We analyzed 4-allylanisole and monoterpene profiles in the xylem oleoresin from a total of 107 trees at six sites from two chemotypes of ponderosa pine found in Colorado and New Mexico using gas chromatography-mass spectroscopy (GC-MS). Although monoterpene profiles were essentially the same in attacked and nonattacked trees, significantly lower levels of 4-allylanisole were found in attacked trees compared with trees that showed no evidence of attack for both chemotypes.

  10. Limited response of ponderosa pine bole defenses to wounding and fungi.

    Science.gov (United States)

    Gaylord, Monica L; Hofstetter, Richard W; Kolb, Thomas E; Wagner, Michael R

    2011-04-01

    Tree defense against bark beetles (Curculionidae: Scolytinae) and their associated fungi generally comprises some combination of constitutive (primary) and induced (secondary) defenses. In pines, the primary constitutive defense against bark beetles consists of preformed resin stored in resin ducts. Induced defenses at the wound site (point of beetle entry) in pines may consist of an increase in resin flow and necrotic lesion formation. The quantity and quality of both induced and constitutive defenses can vary by species and season. The inducible defense response in ponderosa pine is not well understood. Our study examined the inducible defense response in ponderosa pine using traumatic mechanical wounding, and wounding with and without fungal inoculations with two different bark beetle-associated fungi (Ophiostoma minus and Grosmannia clavigera). Resin flow did not significantly increase in response to any treatment. In addition, necrotic lesion formation on the bole after fungal inoculation was minimal. Stand thinning, which has been shown to increase water availability, had no, or inconsistent, effects on inducible tree defense. Our results suggest that ponderosa pine bole defense against bark beetles and their associated fungi is primarily constitutive and not induced.

  11. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon

    Science.gov (United States)

    Michelle C. Agne; David C. Shaw; Travis J. Woolley; Mónica E. Queijeiro-Bolaños; Mai-He. Li

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes....

  12. Changes in Gambel oak densities in southwestern ponderosa pine forests since Euro-American settlement

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Densities of small-diameter ponderosa pine (Pinus ponderosa) trees have increased in southwestern ponderosa pine forests during a period of fire exclusion since Euro-American settlement in the late 1800s. However, less well known are potential changes in Gambel oak (Quercus gambelii) densities during this period in these forests....

  13. Field guide to old ponderosa pines in the Colorado Front Range

    Science.gov (United States)

    Laurie Stroh Huckaby; Merrill R. Kaufmann; Paula J. Fornwalt; Jason M. Stoker; Chuck Dennis

    2003-01-01

    We describe the distinguishing physical characteristics of old ponderosa pine trees in the Front Range of Colorado and the ecological processes that tend to preserve them. Photographs illustrate identifying features of old ponderosa pines and show how to differentiate them from mature and young trees. The publication includes a photographic gallery of old ponderosa...

  14. INTERACTION OF GRASS COMPETITION AND OZONE STRESS ON C/N RATIO IN PONDEROSA PINE

    Science.gov (United States)

    Individual ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedlings were grown with three levels of blue wild-rye grass (Elymus glaucus Buckl.) (0,32, or 88 plants m-2) to determine if the presence of a natural competitor altered ponderosa pine seedling response to ozone. Gras...

  15. ROLE OF CARBOHYDRATE SUPPLY IN WHITE AND BROWN ROOT RESPIRATION OF PONDEROSA PINE

    Science.gov (United States)

    Respiratory responses of fine ponderosa pine (Pinus ponderosa Laws) roots of differing morphology were measured to evaluate response to excision and to changes in the shoot light environment. Ponderosa pine seedlings were subject to either a 15:9 h light/dark environment over 24...

  16. Tree mortality in drought-stressed mixed-conifer and ponderosa pine forests, Arizona, USA

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2011-01-01

    We monitored tree mortality in northern Arizona (USA) mixed-conifer and ponderosa pine (Pinus ponderosa Dougl. ex Laws) forests from 1997 to 2007, a period of severe drought in this area. Mortality was pervasive, occurring on 100 and 98% of 53 mixed-conifer and 60 ponderosa pine plots (1-ha each), respectively. Most mortality was attributable to a suite of forest...

  17. Differences in ponderosa pine isocupressic acid concentrations across space and time

    Science.gov (United States)

    Ponderosa Pine (Pinus ponderosa) is distributed throughout the western half of North America, where it is the most widely adapted and ubiquitous conifer. Ponderosa Pine contains isocupressic acid, a diterpene acid, which has been shown to be responsible for its abortifacient activity. The objectiv...

  18. Suitability of live and fire-killed small-diameter ponderosa and lodgepole pine trees for manufacturing a new structural wood composite.

    Science.gov (United States)

    Linton, J M; Barnes, H M; Seale, R D; Jones, P D; Lowell, E C; Hummel, S S

    2010-08-01

    Finding alternative uses for raw material from small-diameter trees is a critical problem throughout the United States. In western states, a lack of markets for small-diameter ponderosa pine (Pinus ponderosa) and lodgepole pine (Pinus contorta) can contribute to problems associated with overstocking. To test the feasibility of producing structural composite lumber (SCL) beams from these two western species, we used a new technology called steam-pressed scrim lumber (SPSL) based on scrimming technology developed in Australia. Both standing green and fire-killed ponderosa and lodgepole pine logs were used in an initial test. Fire-killed logs of both species were found to be unsuitable for producing SPSL but green logs were suitable for producing SPSL. For SPSL from green material, ponderosa pine had significantly higher modulus of rupture and work-to-maximum load values than did SPSL from lodgepole pine. Modulus of elasticity was higher for lodgepole pine. The presence of blows was greater with lodgepole pine than with ponderosa. Blows had a negative effect on the mechanical properties of ponderosa pine but no significant effect on the mechanical properties of SPSL from lodgepole pine. An evaluation of non-destructive testing methods showed that X-ray could be used to determine low density areas in parent beams. The use of a sonic compression wave tester for NDE evaluation of modulus of rupture showed some promise with SPSL but requires further research. (c) 2010 Elsevier Ltd. All rights reserved.

  19. A test of high-dose verbenone for stand-level protection of lodgepole and whitebark pine from mountain pine beetle (Coleoptera: Curculionidae: Scolytinae) attacks

    Science.gov (United States)

    B. J. Bentz; S. Kegley; K. Gibson; R. Their

    2005-01-01

    The effcacy of verbenone as a stand-level protectant against mountain pine beetle, Dendroctonus ponderosae Hopkins, attacks was tested in lodgepole and whitebark pine stands at five geographically separated sites, including three consecutive years at one site. Forty and 20 high-dose pouches, with a verbenone emission rate up to 50 mg/d per pouch, were spaced in a grid...

  20. Variations in the monoterpene composition of ponderosa pine wood oleoresin

    Science.gov (United States)

    Richard H. Smith

    1964-01-01

    A wide range in quantitative composition of the wood oleoresin monoterpenes was found among 64 ponderosa pines in the central Sierra Nevada by gas chromatographic analysis. An inverse relationship was found in the amount of β-pinene and Δ3-carene. Practically no difference in composition could be associated with (a) type of...

  1. Ponderosa pine seed-tree removal reduces stocking only slightly

    Science.gov (United States)

    Philip M. McDonald

    1969-01-01

    After ponderosa pine seed trees were removed on the Challenge Experimental Forest, California, seedling stocking fell by 3.8 percent or about 212 seedlings per acre. This loss is slightly less than that incurred from natural mortality, and one that did not reduce regeneration levels below the minimum standard.

  2. Silviculture of southwestern ponderosa pine: The status of our knowledge

    Science.gov (United States)

    Gilbert H. Schubert

    1974-01-01

    Describes the status of our knowledge of ponderosa pine silviculture in the southwestern States of Arizona, Colorado, New Mexico, and Utah. Economic value, impact on other uses, and the timber resource are discussed first, followed by ecological background, site quality, growth and yield, and silviculture and management. Relevant literature is discussed along with...

  3. Acoustic analysis of warp potential of green ponderosa pine lumber

    Science.gov (United States)

    Xiping Wang; William T. Simpson

    2005-01-01

    This study evaluated the potential of acoustic analysis as presorting criteria to identify warp-prone boards before kiln drying. Dimension lumber, 38 by 89 mm (nominal 2 by 4 in.) and 2.44 m (8 ft) long, sawn from open-grown small-diameter ponderosa pine trees, was acoustically tested lengthwise at green condition. Three acoustic properties (acoustic speed, rate of...

  4. Methods of cutting ponderosa pine in the Southwest - Establishment report: Even-aged yield study, Plot 11

    Science.gov (United States)

    Gilbert H. Schubert

    1963-01-01

    The objectie of the study is to obtain information on the growth and yield of even-aged stands of different stocking levels. The plot will also serve as the start of a detailed growing stock study for the ponderosa pine region.

  5. Physiological responses of ponderosa pine in western Montana to thinning, prescribed fire and burning season.

    Science.gov (United States)

    Sala, Anna; Peters, Gregory D; McIntyre, Lorna R; Harrington, Michael G

    2005-03-01

    Low-elevation ponderosa pine (Pinus ponderosa Dougl. ex. Laws.) forests of the northern Rocky Mountains historically experienced frequent low-intensity fires that maintained open uneven-aged stands. A century of fire exclusion has contributed to denser ponderosa pine forests with greater competition for resources, higher tree stress and greater risk of insect attack and stand-destroying fire. Active management intended to restore a semblance of the more sustainable historic stand structure and composition includes selective thinning and prescribed fire. However, little is known about the relative effects of these management practices on the physiological performance of ponderosa pine. We measured soil water and nitrogen availability, physiological performance and wood radial increment of second growth ponderosa pine trees at the Lick Creek Experimental Site in the Bitterroot National Forest, Montana, 8 and 9 years after the application of four treatments: thinning only; thinning followed by prescribed fire in the spring; thinning followed by prescribed fire in the fall; and untreated controls. Volumetric soil water content and resin capsule ammonium did not differ among treatments. Resin capsule nitrate in the control treatment was similar to that in all other treatments, although burned treatments had lower nitrate relative to the thinned-only treatment. Trees of similar size and canopy condition in the three thinned treatments (with and without fire) displayed higher leaf-area-based photosynthetic rate, stomatal conductance and mid-morning leaf water potential in June and July, and higher wood radial increment relative to trees in control units. Specific leaf area, mass-based leaf nitrogen content and carbon isotope discrimination did not vary among treatments. Our results suggest that, despite minimal differences in soil resource availability, trees in managed units where basal area was reduced had improved gas exchange and growth compared with trees in

  6. Ecological restoration of southwestern ponderosa pine ecosystems: A broad perspective

    Science.gov (United States)

    Allen, Craig D.; Savage, Melissa; Falk, Donald A.; Suckling, Kieran F.; Swetnam, Thomas W.; Schulke, Todd; Stacey, Peter B.; Morgan, Penelope; Hoffman, Martos; Klingel, Jon T.

    2002-01-01

    The purpose of this paper is to promote a broad and flexible perspective on ecological restoration of Southwestern (U.S.) ponderosa pine forests. Ponderosa pine forests in the region have been radically altered by Euro-American land uses, including livestock grazing, fire suppression, and logging. Dense thickets of young trees now abound, old-growth and biodiversity have declined, and human and ecological communities are increasingly vulnerable to destructive crown fires. A consensus has emerged that it is urgent to restore more natural conditions to these forests. Efforts to restore Southwestern forests will require extensive projects employing varying combinations of young-tree thinning and reintroduction of low-intensity fires. Treatments must be flexible enough to recognize and accommodate: high levels of natural heterogeneity; dynamic ecosystems; wildlife and other biodiversity considerations; scientific uncertainty; and the challenges of on-the-ground implementation. Ecological restoration should reset ecosystem trends toward an envelope of “natural variability,” including the reestablishment of natural processes. Reconstructed historic reference conditions are best used as general guides rather than rigid restoration prescriptions. In the long term, the best way to align forest conditions to track ongoing climate changes is to restore fire, which naturally correlates with current climate. Some stands need substantial structural manipulation (thinning) before fire can safely be reintroduced. In other areas, such as large wilderness and roadless areas, fire alone may suffice as the main tool of ecological restoration, recreating the natural interaction of structure and process. Impatience, overreaction to crown fire risks, extractive economics, or hubris could lead to widespread application of highly intrusive treatments that may further damage forest ecosystems. Investments in research and monitoring of restoration treatments are essential to refine

  7. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae outbreak in pine forests.

    Directory of Open Access Journals (Sweden)

    Gregory J Pec

    Full Text Available The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae in lodgepole pine (Pinus contorta forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  8. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae) outbreak in pine forests.

    Science.gov (United States)

    Pec, Gregory J; Karst, Justine; Sywenky, Alexandra N; Cigan, Paul W; Erbilgin, Nadir; Simard, Suzanne W; Cahill, James F

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  9. Exploring climate niches of ponderosa pine (Pinus ponderosa Douglas ex Lawson) haplotypes in the western United States: implications for evolutionary history and conservation

    Science.gov (United States)

    Douglas J. Shinneman; Robert E. Means; Kevin M. Potter; Valerie D. Hipkins; Tzen-Yuh Chiang

    2016-01-01

    Ponderosa pine (Pinus ponderosa Douglas ex Lawson) occupies montane environments throughout western North America, where it is both an ecologically and economically important tree species. A recent study using mitochondrial DNA analysis demonstrated substantial genetic variation among ponderosa pine populations in the western U.S., identifying 10 haplotypes with unique...

  10. Translocation of 14-C in ponderosa pine seedlings

    Science.gov (United States)

    Robert R. Ziemer

    1971-01-01

    The movement of 14-C from the old needles to the roots, and later to the new needles, was measured in 2-year-old ponderosa pine seedlings. The seedlings were in one of three growth stages at the time of the feeding of 14-CO-2: 9 days before spring bud break with no root activity; 7 days before spring bud break with high root activity; and 7 days after spring bud break...

  11. Tree canopy types constrain plant distributions in ponderosa pine-Gambel oak forests, northern Arizona

    Science.gov (United States)

    Scott R. Abella

    2009-01-01

    Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa...

  12. Climate Drives Episodic Conifer Establishment after Fire in Dry Ponderosa Pine Forests of the Colorado Front Range, USA

    Directory of Open Access Journals (Sweden)

    Monica T. Rother

    2017-05-01

    Full Text Available In recent years, warming climate and increased fire activity have raised concern about post-fire recovery of western U.S. forests. We assessed relationships between climate variability and tree establishment after fire in dry ponderosa pine forests of the Colorado Front Range. We harvested and aged over 400 post-fire juvenile ponderosa pine (Pinus ponderosa and Douglas-fir (Pseudotsuga menziesii trees using an improved tree-ring based approach that yielded annually-resolved dates and then assessed relationships between climate variability and pulses of tree establishment. We found that tree establishment was largely concentrated in years of above-average moisture availability in the growing season, including higher amounts of precipitation and more positive values of the Palmer Drought Severity Index. Under continued climate change, drier conditions associated with warming temperatures may limit forest recovery after fire, which could result in lower stand densities or shifts to non-forested vegetation in some areas.

  13. Bark beetles and dwarf mistletoe interact to alter downed woody material, canopy structure, and stand characteristics in northern Colorado ponderosa pine

    Science.gov (United States)

    Jennifer G. Klutsch; Russell D. Beam; William R. Jacobi; Jose F. Negron

    2014-01-01

    Due to the recent outbreaks of bark beetles in western U.S.A., research has focused on the effects of tree mortality on forest conditions, such as fuel complexes and stand structure. However, most studies have addressed outbreak populations of bark beetles only and there is a lack of information on the effect of multiple endemic, low level populations of biotic...

  14. Spatial patterns of ponderosa pine regeneration in high-severity burn patches

    Science.gov (United States)

    Suzanne M. Owen; Carolyn H. Sieg; Andrew J. Sanchez. Meador; Peter Z. Fule; Jose M. Iniguez; L. Scott. Baggett; Paula J. Fornwalt; Michael A. Battaglia

    2017-01-01

    Contemporary wildfires in southwestern US ponderosa pine forests can leave uncharacteristically large patches of tree mortality, raising concerns about the lack of seed-producing trees, which can prevent or significantly delay ponderosa pine regeneration. We established 4-ha plots in high-severity burn patches in two Arizona wildfires, the 2000 Pumpkin and 2002 Rodeo-...

  15. Estimating cubic volume of small diameter tree-length logs from ponderosa and lodgepole pine.

    Science.gov (United States)

    Marlin E. Plank; James M. Cahill

    1984-01-01

    A sample of 351 ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and 509 lodgepole pine (Pinus contorta Dougl. ex Loud.) logs were used to evaluate the performance of three commonly used formulas for estimating cubic volume. Smalian's formula, Bruce's formula, and Huber's formula were tested to determine which...

  16. Fire effects on Gambel oak in southwestern ponderosa pine-oak forests

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain...

  17. Evaluation of insecticides for protecting southwestern ponderosa pines from attack by engraver beetles (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    Tom E. DeGomez; Christopher J. Hayes; John A. Anhold; Joel D. McMillin; Karen M. Clancy; Paul P. Bosu

    2006-01-01

    Insecticides that might protect pine trees from attack by engraver beetles (Ips spp.) have not been rigorously tested in the southwestern United States. We conducted two field experiments to evaluate the efficacy of several currently and potentially labeled preventative insecticides for protecting high-value ponderosa pine, Pinus ponderosa...

  18. Fire, fuels, and restoration of ponderosa pine-Douglas-fir forests in the Rocky Mountains, USA

    OpenAIRE

    Baker, W. L.; Veblen, T. T.; Sherriff, R. L.

    2007-01-01

    Forest restoration in ponderosa pine and mixed ponderosa pine–Douglas fir forests in the US Rocky Mountains has been highly influenced by a historical model of frequent, low-severity surface fires developed for the ponderosa pine forests of the Southwestern USA. A restoration model, based on this low-severity fire model, focuses on thinning and prescribed burning to restore historical forest structure. However, in the US Rocky Mountains, research on fire history and forest structure, and earl...

  19. Exploring Climate Niches of Ponderosa Pine (Pinus ponderosa Douglas ex Lawson) Haplotypes in the Western United States: Implications for Evolutionary History and Conservation

    OpenAIRE

    Shinneman, Douglas J.; Means, Robert E.; Potter, Kevin M.; Hipkins, Valerie D.

    2016-01-01

    Ponderosa pine (Pinus ponderosa Douglas ex Lawson) occupies montane environments throughout western North America, where it is both an ecologically and economically important tree species. A recent study using mitochondrial DNA analysis demonstrated substantial genetic variation among ponderosa pine populations in the western U.S., identifying 10 haplotypes with unique evolutionary lineages that generally correspond spatially with distributions of the Pacific (P. p. var. ponderosa) and Rocky ...

  20. Feeding response of Ips paraconfusus to phloem and phloem metabolites of Heterobasidion annosum-inoculated ponderosa pine, Pinus ponderosa.

    Science.gov (United States)

    McNee, William R; Bonello, Pierluigi; Storer, Andrew J; Wood, David L; Gordon, Thomas R

    2003-05-01

    In studies of feeding by the bark beetle, Ips paraconfusus, two pine stilbenes (pinosylvin and pinosylvin methyl ether), ferulic acid glucoside, and enantiomers of the four most common sugars present in ponderosa pine phloem (sucrose, glucose, fructose, and raffinose) did not stimulate or reduce male feeding when assayed on wet alpha-cellulose with or without stimulatory phloem extractives present. When allowed to feed on wet alpha-cellulose containing sequential extracts (hexane, methanol, and water) of ponderosa pine phloem, methanol and water extractives stimulated feeding, but hexane extractives did not. Males confined in wet alpha-cellulose containing aqueous or organic extracts of culture broths derived from phloem tissue and containing the root pathogen. Heterobasidion annosum, ingested less substrate than beetles confined to control preparations. In an assay using logs from uninoculated ponderosa pines, the mean lengths of phloem in the digestive tracts increased as time spent feeding increased. Males confined to the phloem of basal logs cut from ponderosa pines artificially inoculated with H. annosum ingested significantly less phloem than beetles in logs cut from trees that were (combined) mock-inoculated or uninoculated and did not contain the pathogen. However, individual pathogen-containing treatments were not significantly different from uninoculated controls. It was concluded that altered feeding rates are not a major factor which may explain why diseased ponderosa pines are colonized by I. paraconfusus.

  1. Impact of a Mountain Pine Beetle Outbreak on Young Lodgepole Pine Stands in Central British Columbia

    Directory of Open Access Journals (Sweden)

    Amalesh Dhar

    2015-09-01

    Full Text Available The current mountain pine beetle (MPB (Dendroctonous ponderosae Hopkins epidemic has severely affected pine forests of Western Canada and killed millions of hectares of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm. forest. Generally, MPB attack larger and older (diameter > 20 cm or >60 years of age trees, but the current epidemic extends this limit with attacks on even younger and smaller trees. The study’s aim was to investigate the extent of MPB attack in young pine stands and its possible impact on stand dynamics. Although MPB attacks were observed in trees as small as 7.5 cm diameter at breast height (DBH and as young as 13 years old, the degree of MPB attack (percent stems ha−1 increased with increasing tree diameter and age class (13–20, 21–40, 41–60, and 61–80 years old (6.4%, 49.4%, 62.6%, and 69.5% attack, respectively, by age class which is greater than that reported from previous epidemics for stands of this age. The mean density of surviving residual structure varied widely among age classes and ecological subzones. Depending on age class, 65% to 77% of the attacked stands could contribute to mid-term timber supply. The surviving residual structure of young stands offers an opportunity to mitigate the effects of MPB-attack on future timber supply, increase age class diversity, and enhance ecological resilience in younger stands.

  2. Ponderosa pine resin defenses and growth: metrics matter.

    Science.gov (United States)

    Hood, Sharon; Sala, Anna

    2015-11-01

    Bark beetles (Coleoptera: Curculionidae, Scolytinae) cause widespread tree mortality in coniferous forests worldwide. Constitutive and induced host defenses are important factors in an individual tree's ability to survive an attack and in bottom-up regulation of bark beetle population dynamics, yet quantifying defense levels is often difficult. For example, in Pinus spp., resin flow is important for resistance to bark beetles but is extremely variable among individuals and within a season. While resin is produced and stored in resin ducts, the specific resin duct metrics that best correlate with resin flow remain unclear. The ability and timing of some pine species to produce induced resin is also not well understood. We investigated (i) the relationships between ponderosa pine (Pinus ponderosa Lawson & C. Lawson) resin flow and axial resin duct characteristics, tree growth and physiological variables, and (ii) if mechanical wounding induces ponderosa pine resin flow and resin ducts in the absence of bark beetles. Resin flow increased later in the growing season under moderate water stress and was highest in faster growing trees. The best predictors of resin flow were nonstandardized measures of resin ducts, resin duct size and total resin duct area, both of which increased with tree growth. However, while faster growing trees tended to produce more resin, models of resin flow using only tree growth were not statistically significant. Further, the standardized measures of resin ducts, density and duct area relative to xylem area, decreased with tree growth rate, indicating that slower growing trees invested more in resin duct defenses per unit area of radial growth, despite a tendency to produce less resin overall. We also found that mechanical wounding induced ponderosa pine defenses, but this response was slow. Resin flow increased after 28 days, and resin duct production did not increase until the following year. These slow induced responses may allow

  3. Emergence of Buprestidae, Cerambycidae, and Scolytinae (Coleoptera) from mountain pine beetle-killed and fire-killed ponderosa pines in the Black Hills, South Dakota, USA

    Science.gov (United States)

    Sheryl L. Costello; William R. Jacobi; Jose F. Negron

    2013-01-01

    Wood borers (Coleoptera: Cerambycidae and Buprestidae) and bark beetles (Coleoptera: Curculionidae) infest ponderosa pines, Pinus ponderosa P. Lawson and C. Lawson, killed by mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, and fire. No data is available comparing wood borer and bark beetle densities or species guilds associated with MPB-killed or fire-...

  4. Reticulate evolution and incomplete lineage sorting among the ponderosa pines.

    Science.gov (United States)

    Willyard, Ann; Cronn, Richard; Liston, Aaron

    2009-08-01

    Interspecific gene flow via hybridization may play a major role in evolution by creating reticulate rather than hierarchical lineages in plant species. Occasional diploid pine hybrids indicate the potential for introgression, but reticulation is hard to detect because ancestral polymorphism is still shared across many groups of pine species. Nucleotide sequences for 53 accessions from 17 species in subsection Ponderosae (Pinus) provide evidence for reticulate evolution. Two discordant patterns among independent low-copy nuclear gene trees and a chloroplast haplotype are better explained by introgression than incomplete lineage sorting or other causes of incongruence. Conflicting resolution of three monophyletic Pinus coulteri accessions is best explained by ancient introgression followed by a genetic bottleneck. More recent hybridization transferred a chloroplast from P. jeffreyi to a sympatric P. washoensis individual. We conclude that incomplete lineage sorting could account for other examples of non-monophyly, and caution against any analysis based on single-accession or single-locus sampling in Pinus.

  5. Mountain Pine Beetle Host Selection Between Lodgepole and Ponderosa Pines in the Southern Rocky Mountains.

    Science.gov (United States)

    West, Daniel R; Briggs, Jennifer S; Jacobi, William R; Negrón, José F

    2016-02-01

    Recent evidence of range expansion and host transition by mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB) has suggested that MPB may not primarily breed in their natal host, but will switch hosts to an alternate tree species. As MPB populations expanded in lodgepole pine forests in the southern Rocky Mountains, we investigated the potential for movement into adjacent ponderosa pine forests. We conducted field and laboratory experiments to evaluate four aspects of MPB population dynamics and host selection behavior in the two hosts: emergence timing, sex ratios, host choice, and reproductive success. We found that peak MPB emergence from both hosts occurred simultaneously between late July and early August, and the sex ratio of emerging beetles did not differ between hosts. In two direct tests of MPB host selection, we identified a strong preference by MPB for ponderosa versus lodgepole pine. At field sites, we captured naturally emerging beetles from both natal hosts in choice arenas containing logs of both species. In the laboratory, we offered sections of bark and phloem from both species to individual insects in bioassays. In both tests, insects infested ponderosa over lodgepole pine at a ratio of almost 2:1, regardless of natal host species. Reproductive success (offspring/female) was similar in colonized logs of both hosts. Overall, our findings suggest that MPB may exhibit equally high rates of infestation and fecundity in an alternate host under favorable conditions. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Identifying ponderosa pines infested with mountain pine beetles

    Science.gov (United States)

    William F. McCambridge

    1974-01-01

    Trees successfully and unsuccessfully attacked by mountain pine beetles have several symptoms in common, so that proper diagnosis is not always easy. Guidelines presented here enable the observer to correctly distinguish nearly all attacked trees.

  7. Ponderosa pine mortality resulting from a mountain pine beetle outbreak

    Science.gov (United States)

    William F. McCambridge; Frank G. Hawksworth; Carleton B. Edminster; John G. Laut

    1982-01-01

    From 1965 to 1978, mountain pine beetles killed 25% of the pines taller than 4.5 feet in a study area in north-central Colorado. Average basal area was reduced from 92 to 58 square feet per acre. Mortality increased with tree diameter up to about 9 inches d.b.h. Larger trees appeared to be killed at random. Mortality was directly related to number of trees per acre and...

  8. Pezizalean mycorrhizas and sporocarps in ponderosa pine (Pinus ponderosa) after prescribed fires in eastern Oregon, USA.

    Science.gov (United States)

    Fujimura, K E; Smith, J E; Horton, T R; Weber, N S; Spatafora, J W

    2005-03-01

    Post-fire Pezizales fruit commonly in many forest types after fire. The objectives of this study were to determine which Pezizales appeared as sporocarps after a prescribed fire in the Blue Mountains of eastern Oregon, and whether species of Pezizales formed mycorrhizas on ponderosa pine, whether or not they were detected from sporocarps. Forty-two sporocarp collections in five genera (Anthracobia, Morchella, Peziza, Scutellinia, Tricharina) of post-fire Pezizales produced ten restriction fragment length polymorphism (RFLP) types. We found no root tips colonized by species of post-fire Pezizales fruiting at our site. However, 15% (6/39) of the RFLP types obtained from mycorrhizal roots within 32 soil cores were ascomycetes. Phylogenetic analyses of the 18S nuclear ribosomal DNA gene indicated that four of the six RFLP types clustered with two genera of the Pezizales, Wilcoxina and Geopora. Subsequent analyses indicated that two of these mycobionts were probably Wilcoxina rehmii, one Geopora cooperi, and one Geopora sp. The identities of two types were not successfully determined with PCR-based methods. Results contribute knowledge about the above- and below-ground ascomycete community in a ponderosa pine forest after a low intensity fire.

  9. COMBINED EFFECTS OF CO2 AND O3 ON ANTIOXIDATIVE AND PHOTOPROTECTIVE DEFENSE SYSTEMS IN NEEDLES OF PONDEROSA PINE

    Science.gov (United States)

    To determine interactive effects of important environmental stresses on biochemical defense mechanisms of tree seedlings, we studied responses to elevated O3 and elevated atmospheric CO2 on antioxidative and photoprotective systems in needles of ponderosa pine (Pinus ponderosa Do...

  10. Seasonal changes in above- and belowground carbohydrate concentrations of ponderosa pine along a pollution gradient

    Science.gov (United States)

    Nancy E. Grulke; Chris P. Andersen; William E. Hogsett

    2001-01-01

    Seasonal patterns of carbohydrate concentration in coarse and fine roots, stem or bole, and foliage of ponderosa pine (Pinus ponderosa Laws) were described across five treeage classes from seedlings to mature trees at an atmospherically clean site. Relative to all other tree-age classes, seedlings exhibited greater tissue carbohydrate concentration...

  11. Use of Hardwood Tree Species by Birds Nesting in Ponderosa Pine Forests

    Science.gov (United States)

    Kathryn L. Purcell; Douglas A. Drynan

    2008-01-01

    We examined the use of hardwood tree species for nesting by bird species breeding in ponderosa pine (Pinus ponderosa) forests in the Sierra National Forest, California. From 1995 through 2002, we located 668 nests of 36 bird species nesting in trees and snags on four 60-ha study sites. Two-thirds of all species nesting in trees or snags used...

  12. EFFECTS OF ELEVATED CO2 AND N-FERTILIZATION ON SURVIVAL OF PONDEROSA PINE FINE ROOTS

    Science.gov (United States)

    We used minihizaotrons to assess the effects of elevated CO2N and season on the life-span of ponderosa pine (Pinus ponderosa Dougl. Ex Laws.) fine roots. CO2 levels were ambient air (A), ambient air + 175 ?mol mol-1 (A+175) and ambient air + 350 ?mol mol-1 (A+350). N treatments ...

  13. Bark beetle-caused mortality in a drought-affected ponderosa pine landscape in Arizona, USA

    Science.gov (United States)

    Jose F. Negron; Joel D. McMillin; John A. Anhold; Dave Coulson

    2009-01-01

    Extensive ponderosa pine (Pinus ponderosa Dougl. ex Laws.) mortality associated with a widespread severe drought and increased bark beetle (Coleoptera: Curculionidae, Scolytinae) populations occurred in Arizona from 2001 to 2004. A complex of Ips beetles including: the Arizona fivespined ips, Ips lecontei Swaine...

  14. Coarse woody debris assay in northern Arizona mixed-conifer and ponderosa pine forests

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2010-01-01

    Coarse woody debris (CWD) provides important ecosystem services in forests and affects fire behavior, yet information on amounts and types of CWD typically is limited. To provide such information, we sampled logs and stumps in mixed-conifer and ponderosa pine (Pinus ponderosa) forests in north-central Arizona. Spatial variability was prominent for all CWD parameters....

  15. Predicting mortality of ponderosa pine regeneration after prescribed fire in the Black Hills, South Dakota, USA

    Science.gov (United States)

    Mike Battaglia; Frederick W. Smith; Wayne D. Shepperd

    2009-01-01

    Reduction of crown fire hazard in Pinus ponderosa forests in the Black Hills, SD, often focuses on the removal of overstorey trees to reduce crown bulk density. Dense ponderosa pine regeneration establishes several years after treatment and eventually increases crown fire risk if allowed to grow. Using prescribed fire to control this regeneration is...

  16. Effectiveness of litter removal to prevent cambial kill-caused mortality in northern Arizona ponderosa pine

    Science.gov (United States)

    James F. Fowler; Carolyn Hull Sieg; Linda L. Wadleigh

    2010-01-01

    Removal of deep litter and duff from the base of mature southwestern ponderosa pine (Pinus ponderosa Laws.) is commonly recommended to reduce mortality after prescribed burns, but experimental studies that quantify the effectiveness of such practices in reducing mortality are lacking. After a pilot study on each of four sites in northern Arizona, we monitored 15-16...

  17. The 2002 Rodeo-Chediski Wildfire's impacts on southwestern ponderosa pine ecosystems, hydrology, and fuels

    Science.gov (United States)

    Peter F. Ffolliott; Cody L. Stropki; Hui Chen; Daniel G. Neary

    2011-01-01

    The Rodeo-Chediski Wildfire burned nearly 462,600 acres in north-central Arizona in the summer of 2002. The wildfire damaged or destroyed ecosystem resources and disrupted the hydrologic functioning within the impacted ponderosa pine (Pinus ponderosa) forests in a largely mosaic pattern. Impacts of the wildfire on ecosystem resources, factors important to hydrologic...

  18. Accumulation of cesium-137 and strontium-90 in ponderosa pine and monterey pine seedlings

    International Nuclear Information System (INIS)

    Entry, J.A.; Rygiewicz, P.T.; Emmingham, W.H.

    1993-01-01

    Because ponderosa pine Pinus ponderosa and Monterey pone (P. radiata D Don) have exceptionally fast growth rates and their abscised needles are not readily dispersed by wind, these species may be valuable for removing radioisotopes from contaminated soils. Ponderosa and Monterey pine seedlings were tested for their ability to accumulate 137 Cs and 90 Sr-characteristic radioisotopes of nuclear fallout-from contaminated soil. Seedlings were grown for 3 mo in 165 cm 3 sphagnum peat moss/perlite (1:1 V/V) in a growth chamber. In Exp. 1, seedling accumulation of 137 Cs and 90 Sr after 1 mo of exposure was measured. In Exp. 2, seedling accumulation of the radioisotopes during different-length exposures was measured. Seedling accumulation of 137 CS and 90 Sr at different concentrations of the radioisotopes in the growth medium was measured in Exp. 3. Ponderosa pine accumulated 6.3% of the 137 Cs and I.5% of the 90 Sr present in the growth medium after 1 mo; Monterey pine accumulated 8.3% of the 137 Cs and 4.5% of the 90 Sr. Accumulation of 137 Cs and 90 Sr by both coniferous species was curvilinearly related to duration of exposure. Accumulation of 137 Cs and 90 Sr by both species increased with increasing concentration in the growth medium and correlated curvilinearly with radioisotope concentration in the growth medium. Large areas throughout the world are contaminated with 137 Cs and 90 Sr as a result of nuclear weapons testing or atomic reactor accidents. The ability of trees to sequester and store 137 Cs and 90 Sr introduces the possibility of using reforestation to remediate contaminated soils

  19. Resource Limitations Influence Growth and Vigor of Idaho Fescue, a Common Understory Species in Pacific Northwest Ponderosa Pine Forests

    Directory of Open Access Journals (Sweden)

    Craig A. Carr

    2016-12-01

    Full Text Available Alterations in under-canopy resource availability associated with elevated ponderosa pine (Pinus ponderosa Dougl. abundance can negatively influence understory vegetation. Experimental evidence linking under-canopy resource availability and understory vegetation is scarce. Yet this information would be beneficial in developing management strategies to recover desired understory species. We tested the effects of varying nitrogen (N and light availability on Idaho fescue (Festuca idahoensis Elmer, the dominant understory species in ponderosa pine/Idaho fescue plant associations in eastern Oregon. In a greenhouse experiment, two levels of N (50 kg∙N∙ha−1 and 0 kg∙N∙ha−1 and shade (80% shade and 0% shade were applied in a split-plot design to individual potted plants grown in soil collected from high abundance pine stands. Plants grown in unshaded conditions produced greater root (p = 0.0027 and shoot (p = 0.0017 biomass and higher cover values (p = 0.0378 compared to those in the shaded treatments. The addition of N had little effect on plant growth (p = 0.1602, 0.5129, and 0.0853 for shoot biomass, root biomass, and cover, respectively, suggesting that soils in high-density ponderosa pine stands that lack understory vegetation were not N deficient and Idaho fescue plants grown in these soils were not N limited. Management activities that increase under-canopy light availability will promote the conditions necessary for Idaho fescue recovery. However, successful restoration may be constrained by a lack of residual fescue or the invasion of more competitive understory vegetation.

  20. Carbon Stocks and Climate Change: Management Implications in Northern Arizona Ponderosa Pine Forests

    Directory of Open Access Journals (Sweden)

    Benjamin Bagdon

    2014-04-01

    Full Text Available Researchers have observed climate-driven shifts of forest types to higher elevations in the Southwestern US and predict further migration coupled with large-scale mortality events proportional to increases in radiative forcing. Range contractions of forests are likely to impact the total carbon stored within a stand. This study examines the dynamics of Pinus ponderosa stands under three climate change scenarios in Northern Arizona using the Climate Forest Vegetation Simulator (Climate-FVS model to project changes in carbon pools. A sample of 90 stands were grouped according to three elevational ranges; low- (1951 to 2194 m, mid- (2194 to 2499 m, and high- (2499 to 2682 m. elevation stands. Growth, mortality, and carbon stores were simulated in the Climate-FVS over a 100 year timespan. We further simulated three management scenarios for each elevational gradient and climate scenario. Management included (1 a no-management scenario, (2 an intensive-management scenario characterized by thinning from below to a residual basal area (BA of 18 m2/ha in conjunction with a prescribed burn every 10 years, and (3 a moderate-management scenario characterized by a thin-from-below treatment to a residual BA of 28 m2/ha coupled with a prescribed burn every 20 years. Results indicate that any increase in aridity due to climate change will produce substantial mortality throughout the elevational range of ponderosa pine stands, with lower elevation stands projected to experience the most devastating effects. Management was only effective for the intensive-management scenario; stands receiving this treatment schedule maintained moderately consistent levels of basal area and demonstrated a higher level of resilience to climate change relative to the two other management scenarios. The results of this study indicate that management can improve resiliency to climate change, however, resource managers may need to employ more intensive thinning treatments than

  1. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae

    Directory of Open Access Journals (Sweden)

    Erin L. Clark

    2014-02-01

    Full Text Available The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC, where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle’s historic range (central BC to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC and one population of jack pine (AB were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels – a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle – were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the

  2. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae).

    Science.gov (United States)

    Clark, Erin L; Pitt, Caitlin; Carroll, Allan L; Lindgren, B Staffan; Huber, Dezene P W

    2014-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC), where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle's historic range (central BC) to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB) in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC) and one population of jack pine (AB) were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels - a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle - were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the insect to persist in

  3. Studies on black stain root disease in ponderosa pine. pp. 236-240. M. Garbelotto & P. Gonthier (Editors). Proceedings 12th International Conference on Root and Butt Rots of Forest Trees.

    Science.gov (United States)

    W. J. Otrosina; J. T. Kliejunas; S. S. Sung; S. Smith; D. R. Cluck

    2008-01-01

    Black stain root disease of ponderosa pine, caused by Lepfographium wageneri var. ponderosum (Harrington & Cobb) Harrington & Cobb, is increasing on many eastside pine stands in northeastern California. The disease is spread from tree to tree via root contacts and grafts but new infections are likely vectored by root...

  4. Geographic variation in speed of seed germination in central Oregon ponderosa pine (Pinus ponderosa Dougl. ex Laws.).

    Science.gov (United States)

    John C. Weber; Frank C. Sorensen

    1992-01-01

    Variation in speed of seed germination was investigated among ponderosa pine trees representing 225 locations in central Oregon. Results suggested that at least some of the geographic variation is related to the severity of summer drought. In general, germination speed was greater in locations with shod, drought-limited growing seasons. Levels of geographic variation...

  5. Thermal conditions within tree cavities in ponderosa pine (Pinus ponderosa) forests: potential implications for cavity users

    Science.gov (United States)

    Vierling, Kerri T.; Lorenz, Teresa J.; Cunningham, Patrick; Potterf, Kelsi

    2017-11-01

    Tree cavities provide critical roosting and breeding sites for multiple species, and thermal environments in these cavities are important to understand. Our objectives were to (1) describe thermal characteristics in cavities between June 3 and August 9, 2014, and (2) investigate the environmental factors that influence cavity temperatures. We placed iButtons in 84 different cavities in ponderosa pine (Pinus ponderosa) forests in central Washington, and took hourly measurements for at least 8 days in each cavity. Temperatures above 40 °C are generally lethal to developing avian embryos, and 18% of the cavities had internal temperatures of ≥ 40 °C for at least 1 h of each day. We modeled daily maximum cavity temperature, the amplitude of daily cavity temperatures, and the difference between the mean internal cavity and mean ambient temperatures as a function of several environmental variables. These variables included canopy cover, tree diameter at cavity height, cavity volume, entrance area, the hardness of the cavity body, the hardness of the cavity sill (which is the wood below the cavity entrance which forms the barrier between the cavity and the external environment), and sill width. Ambient temperature had the largest effect size for maximum cavity temperature and amplitude. Larger trees with harder sills may provide more thermally stable cavity environments, and decayed sills were positively associated with maximum cavity temperatures. Summer temperatures are projected to increase in this region, and additional research is needed to determine how the thermal environments of cavities will influence species occupancy, breeding, and survival.

  6. Monoterpene emissions from a Ponderosa Pine forest. Does age matter?

    Science.gov (United States)

    Madronich, M. B.; Guenther, A. B.; Wessman, C. A.

    2011-12-01

    Determining the emissions rate of biogenic volatile organic carbon (BVOC) from plants is a challenge. Biological variability makes it difficult to assess accurately those emissions rates. It is known that photosynthetic active radiation (PAR), temperature, nutrients as well as the biology of the plant affect emissions. However, less is known about the variability of the emissions with respect to the life cycle of the plants. This study is focusing on the difference of monoterpene emission rates from mature Ponderosa Pine trees and saplings in the field. Preliminary calculations show that there is a significant difference between total monoterpene emissions in mature trees (0.24±0.04 μgC/gdwh) and saplings (0.37±0.02 μgC/gdwh).

  7. Interactive effects of historical logging and fire exclusion on ponderosa pine forest structure in the northern Rockies.

    Science.gov (United States)

    Naficy, Cameron; Sala, Anna; Keeling, Eric G; Graham, Jon; DeLuca, Thomas H

    2010-10-01

    Increased forest density resulting from decades of fire exclusion is often perceived as the leading cause of historically aberrant, severe, contemporary wildfires and insect outbreaks documented in some fire-prone forests of the western United States. Based on this notion, current U.S. forest policy directs managers to reduce stand density and restore historical conditions in fire-excluded forests to help minimize high-severity disturbances. Historical logging, however, has also caused widespread change in forest vegetation conditions, but its long-term effects on vegetation structure and composition have never been adequately quantified. We document that fire-excluded ponderosa pine forests of the northern Rocky Mountains logged prior to 1960 have much higher average stand density, greater homogeneity of stand structure, more standing dead trees and increased abundance of fire-intolerant trees than paired fire-excluded, unlogged counterparts. Notably, the magnitude of the interactive effect of fire exclusion and historical logging substantially exceeds the effects of fire exclusion alone. These differences suggest that historically logged sites are more prone to severe wildfires and insect outbreaks than unlogged, fire-excluded forests and should be considered a high priority for fuels reduction treatments. Furthermore, we propose that ponderosa pine forests with these distinct management histories likely require distinct restoration approaches. We also highlight potential long-term risks of mechanical stand manipulation in unlogged forests and emphasize the need for a long-term view of fuels management.

  8. Presence of carbaryl in the smoke of treated lodgepole and ponderosa pine bark

    Science.gov (United States)

    Chris J. Peterson; Sheryl L. Costello

    2013-01-01

    Lodgepole and ponderosa pine trees were treated with a 2% carbaryl solution at recreational areas near Fort Collins, CO, in June 2010 as a prophylactic bole spray against the mountain pine beetle. Bark samples from treated and untreated trees were collected one day following application and at 4-month intervals for one year. The residual amount of carbaryl was...

  9. Latent resilience in ponderosa pine forest: effects of resumed frequent fire.

    Science.gov (United States)

    Larson, Andrew J; Belote, R Travis; Cansler, C Alina; Parks, Sean A; Dietz, Matthew S

    2013-09-01

    Ecological systems often exhibit resilient states that are maintained through negative feedbacks. In ponderosa pine forests, fire historically represented the negative feedback mechanism that maintained ecosystem resilience; fire exclusion reduced that resilience, predisposing the transition to an alternative ecosystem state upon reintroduction of fire. We evaluated the effects of reintroduced frequent wildfire in unlogged, fire-excluded, ponderosa pine forest in the Bob Marshall Wilderness, Montana, USA. Initial reintroduction of fire in 2003 reduced tree density and consumed surface fuels, but also stimulated establishment of a dense cohort of lodgepole pine, maintaining a trajectory toward an alternative state. Resumption of a frequent fire regime by a second fire in 2011 restored a low-density forest dominated by large-diameter ponderosa pine by eliminating many regenerating lodgepole pines and by continuing to remove surface fuels and small-diameter lodgepole pine and Douglas-fir that established during the fire suppression era. Our data demonstrate that some unlogged, fire-excluded, ponderosa pine forests possess latent resilience to reintroduced fire. A passive model of simply allowing lightning-ignited fires to burn appears to be a viable approach to restoration of such forests.

  10. Areas of Agreement and Disagreement Regarding Ponderosa Pine and Mixed Conifer Forest Fire Regimes: A Dialogue with Stevens et al.

    Directory of Open Access Journals (Sweden)

    Dennis C Odion

    Full Text Available In a recent PLOS ONE paper, we conducted an evidence-based analysis of current versus historical fire regimes and concluded that traditionally defined reference conditions of low-severity fire regimes for ponderosa pine (Pinus ponderosa and mixed-conifer forests were incomplete, missing considerable variability in forest structure and fire regimes. Stevens et al. (this issue agree that high-severity fire was a component of these forests, but disagree that one of the several sources of evidence, stand age from a large number of forest inventory and analysis (FIA plots across the western USA, support our findings that severe fire played more than a minor role ecologically in these forests. Here we highlight areas of agreement and disagreement about past fire, and analyze the methods Stevens et al. used to assess the FIA stand-age data. We found a major problem with a calculation they used to conclude that the FIA data were not useful for evaluating fire regimes. Their calculation, as well as a narrowing of the definition of high-severity fire from the one we used, leads to a large underestimate of conditions consistent with historical high-severity fire. The FIA stand age data do have limitations but they are consistent with other landscape-inference data sources in supporting a broader paradigm about historical variability of fire in ponderosa and mixed-conifer forests than had been traditionally recognized, as described in our previous PLOS paper.

  11. Areas of Agreement and Disagreement Regarding Ponderosa Pine and Mixed Conifer Forest Fire Regimes: A Dialogue with Stevens et al.

    Science.gov (United States)

    Odion, Dennis C; Hanson, Chad T; Baker, William L; DellaSala, Dominick A; Williams, Mark A

    2016-01-01

    In a recent PLOS ONE paper, we conducted an evidence-based analysis of current versus historical fire regimes and concluded that traditionally defined reference conditions of low-severity fire regimes for ponderosa pine (Pinus ponderosa) and mixed-conifer forests were incomplete, missing considerable variability in forest structure and fire regimes. Stevens et al. (this issue) agree that high-severity fire was a component of these forests, but disagree that one of the several sources of evidence, stand age from a large number of forest inventory and analysis (FIA) plots across the western USA, support our findings that severe fire played more than a minor role ecologically in these forests. Here we highlight areas of agreement and disagreement about past fire, and analyze the methods Stevens et al. used to assess the FIA stand-age data. We found a major problem with a calculation they used to conclude that the FIA data were not useful for evaluating fire regimes. Their calculation, as well as a narrowing of the definition of high-severity fire from the one we used, leads to a large underestimate of conditions consistent with historical high-severity fire. The FIA stand age data do have limitations but they are consistent with other landscape-inference data sources in supporting a broader paradigm about historical variability of fire in ponderosa and mixed-conifer forests than had been traditionally recognized, as described in our previous PLOS paper.

  12. Quantum Yields in Mixed-Conifer Forests and Ponderosa Pine Plantations

    Science.gov (United States)

    Wei, L.; Marshall, J. D.; Zhang, J.

    2008-12-01

    Most process-based physiological models require canopy quantum yield of photosynthesis as a starting point to simulate carbon sequestration and subsequently gross primary production (GPP). The quantum yield is a measure of photosynthetic efficiency expressed in moles of CO2 assimilated per mole of photons absorbed; the process is influenced by environmental factors. In the summer 2008, we measured quantum yields on both sun and shade leaves for four conifer species at five sites within Mica Creek Experimental Watershed (MCEW) in northern Idaho and one conifer species at three sites in northern California. The MCEW forest is typical of mixed conifer stands dominated by grand fir (Abies grandis (Douglas ex D. Don) Lindl.). In northern California, the three sites with contrasting site qualities are ponderosa pine (Pinus ponderosa C. Lawson var. ponderosa) plantations that were experimentally treated with vegetation control, fertilization, and a combination of both. We found that quantum yields in MCEW ranged from ~0.045 to ~0.075 mol CO2 per mol incident photon. However, there were no significant differences between canopy positions, or among sites or tree species. In northern California, the mean value of quantum yield of three sites was 0.051 mol CO2/mol incident photon. No significant difference in quantum yield was found between canopy positions, or among treatments or sites. The results suggest that these conifer species maintain relatively consistent quantum yield in both MCEW and northern California. This consistency simplifies the use of a process-based model to accurately predict forest productivity in these areas.

  13. Intraspecific niche models for ponderosa pine (Pinus ponderosa) suggest potential variability in population-level response to climate change

    Science.gov (United States)

    Maguire, Kaitlin C.; Shinneman, Douglas; Potter, Kevin M.; Hipkins, Valerie D.

    2018-01-01

    Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at the species level, often because intraspecific variation is unknown or is identified only within limited sample locations. In this study, we considered the role of intraspecific variation to shape the geographic distribution of ponderosa pine (Pinus ponderosa), an ecologically and economically important tree species in North America. Morphological and genetic variation across the distribution of ponderosa pine suggest the need to model intraspecific populations: the two varieties (var. ponderosa and var. scopulorum) and several haplotype groups within each variety have been shown to occupy unique climatic niches, suggesting populations have distinct evolutionary lineages adapted to different environmental conditions. We utilized a recently-available, geographically-widespread dataset of intraspecific variation (haplotypes) for ponderosa pine and a recently-devised lineage distance modeling approach to derive additional, likely intraspecific occurrence locations. We confirmed the relative uniqueness of each haplotype-climate relationship using a niche-overlap analysis, and developed ecological niche models (ENMs) to project the distribution for two varieties and eight haplotypes under future climate forecasts. Future projections of haplotype niche distributions generally revealed greater potential range loss than predicted for the varieties. This difference may reflect intraspecific responses of distinct evolutionary lineages. However, directional trends are generally consistent across intraspecific levels, and include a loss of distributional area and an upward shift in elevation. Our results

  14. Intraspecific niche models for ponderosa pine (Pinus ponderosa) suggest potential variability in population-level response to climate change.

    Science.gov (United States)

    Maguire, Kaitlin C; Shinneman, Douglas J; Potter, Kevin M; Hipkins, Valerie D

    2018-03-14

    Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at the species level, often because intraspecific variation is unknown or is identified only within limited sample locations. In this study, we considered the role of intraspecific variation to shape the geographic distribution of ponderosa pine (Pinus ponderosa), an ecologically and economically important tree species in North America. Morphological and genetic variation across the distribution of ponderosa pine suggest the need to model intraspecific populations: the two varieties (var. ponderosa and var. scopulorum) and several haplotype groups within each variety have been shown to occupy unique climatic niches, suggesting populations have distinct evolutionary lineages adapted to different environmental conditions. We utilized a recently-available, geographically-widespread dataset of intraspecific variation (haplotypes) for ponderosa pine and a recently-devised lineage distance modeling approach to derive additional, likely intraspecific occurrence locations. We confirmed the relative uniqueness of each haplotype-climate relationship using a niche-overlap analysis, and developed ecological niche models (ENMs) to project the distribution for two varieties and eight haplotypes under future climate forecasts. Future projections of haplotype niche distributions generally revealed greater potential range loss than predicted for the varieties. This difference may reflect intraspecific responses of distinct evolutionary lineages. However, directional trends are generally consistent across intraspecific levels, and include a loss of distributional area and an upward shift in elevation. Our results

  15. Late Holocene geomorphic record of fire in ponderosa pine and mixed-conifer forests, Kendrick Mountain, northern Arizona, USA

    Science.gov (United States)

    Jenkins, S.E.; Hull, Sieg C.; Anderson, D.E.; Kaufman, D.S.; Pearthree, P.A.

    2011-01-01

    Long-term fire history reconstructions enhance our understanding of fire behaviour and associated geomorphic hazards in forested ecosystems. We used 14C ages on charcoal from fire-induced debris-flow deposits to date prehistoric fires on Kendrick Mountain, northern Arizona, USA. Fire-related debris-flow sedimentation dominates Holocene fan deposition in the study area. Radiocarbon ages indicate that stand-replacing fire has been an important phenomenon in late Holocene ponderosa pine (Pinus ponderosa) and ponderosa pine-mixed conifer forests on steep slopes. Fires have occurred on centennial scales during this period, although temporal hiatuses between recorded fires vary widely and appear to have decreased during the past 2000 years. Steep slopes and complex terrain may be responsible for localised crown fire behaviour through preheating by vertical fuel arrangement and accumulation of excessive fuels. Holocene wildfire-induced debris flow events occurred without a clear relationship to regional climatic shifts (decadal to millennial), suggesting that interannual moisture variability may determine fire year. Fire-debris flow sequences are recorded when (1) sufficient time has passed (centuries) to accumulate fuels; and (2) stored sediment is available to support debris flows. The frequency of reconstructed debris flows should be considered a minimum for severe events in the study area, as fuel production may outpace sediment storage. ?? IAWF 2011.

  16. Pelletized ponderosa pine bark for adsorption of toxic heavy metals from water

    Science.gov (United States)

    Miyoung Oh; Mandla A. Tshabalala

    2007-01-01

    Bark flour from ponderosa pine (Pinus ponderosa) was consolidated into pellets using citric acid as cross-linking agent. The pellets were evaluated for removal of toxic heavy metals from synthetic aqueous solutions. When soaked in water, pellets did not leach tannins, and they showed high adsorption capacity for Cu(ll), Zn(ll), Cd(ll). and Ni(ll) under both equilibrium...

  17. The health of loblolly pine stands at Fort Benning, GA

    Science.gov (United States)

    Soung-Ryoul Ryu; G. Geoff Wang; Joan L. Walker

    2013-01-01

    Approximately two-thirds of the red-cockaded woodpecker (Picoides borealis) (RCW) groups at Fort Benning, GA, depend on loblolly pine (Pinus taeda) stands for nesting or foraging. However, loblolly pine stands are suspected to decline. Forest managers want to replace loblolly pine with longleaf pine (P. palustris...

  18. Examining historical and current mixed-severity fire regimes in ponderosa pine and mixed-conifer forests of western North America.

    Directory of Open Access Journals (Sweden)

    Dennis C Odion

    Full Text Available There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of historical fire regimes in the ponderosa pine and mixed-conifer forests of western North America is therefore needed to define reference conditions and help maintain characteristic ecological diversity of these systems. We compiled landscape-scale evidence of historical fire severity patterns in the ponderosa pine and mixed-conifer forests from published literature sources and stand ages available from the Forest Inventory and Analysis program in the USA. The consensus from this evidence is that the traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire. Diverse forests in different stages of succession, with a high proportion in relatively young stages, occurred prior to fire exclusion. Over the past century, successional diversity created by fire decreased. Our findings suggest that ecological management goals that incorporate successional diversity created by fire may support characteristic biodiversity, whereas current attempts to "restore" forests to open, low-severity fire conditions may not align with historical reference conditions in

  19. Examining historical and current mixed-severity fire regimes in ponderosa pine and mixed-conifer forests of western North America.

    Science.gov (United States)

    Odion, Dennis C; Hanson, Chad T; Arsenault, André; Baker, William L; Dellasala, Dominick A; Hutto, Richard L; Klenner, Walt; Moritz, Max A; Sherriff, Rosemary L; Veblen, Thomas T; Williams, Mark A

    2014-01-01

    There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws) and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of historical fire regimes in the ponderosa pine and mixed-conifer forests of western North America is therefore needed to define reference conditions and help maintain characteristic ecological diversity of these systems. We compiled landscape-scale evidence of historical fire severity patterns in the ponderosa pine and mixed-conifer forests from published literature sources and stand ages available from the Forest Inventory and Analysis program in the USA. The consensus from this evidence is that the traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire. Diverse forests in different stages of succession, with a high proportion in relatively young stages, occurred prior to fire exclusion. Over the past century, successional diversity created by fire decreased. Our findings suggest that ecological management goals that incorporate successional diversity created by fire may support characteristic biodiversity, whereas current attempts to "restore" forests to open, low-severity fire conditions may not align with historical reference conditions in most ponderosa

  20. To live fast or not: growth, vigor and longevity of old-growth ponderosa pine and lodgepole pine trees

    Energy Technology Data Exchange (ETDEWEB)

    Kaufmann, M. R. [Forest Service, Fort Collins, CO (United States). Rocky Mountain Forest and Range Experiment Station

    1996-01-01

    Old ponderosa pine and lodgepole pine trees were studied to determine volume growth patterns in relation to leaf area. Ponderosa pine trees varied in age from 166 to 432 years and were about 77 inches in diameter; lodgepole pine trees ranged in age from 250 to 296 years and were 31 inches in diameter. Trees of both species had flat tops, heavy branches and foliage distribution characteristic of older trees. Annual volume increments were determined from crossdated radial increments measured on discs at four meter height intervals; leaf areas were determined based on leaf area/branch sapwood area ratios. Ponderosa pine volume growth was found to have been gradual at first, reaching a plateau that persisted for a century or more, followed by a rapid increase, and a sudden decrease in growth to less than one half of the earlier rate and persisting at these levels for several decades. In lodgepole pine growth decline was less frequent and less spectacular; growth in general was more even, with slight annual variations. Volume growth in the most recent years prior to felling weakly correlated with leaf area. Growth efficiencies were generally higher for trees having the lowest leaf areas. The fact that these persisted for many decades with low growth efficiencies suggests that defence mechanisms are more effective in old trees than in younger ones. 16 refs., 8 figs.

  1. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    Directory of Open Access Journals (Sweden)

    Michelle C Agne

    Full Text Available Lodgepole pine (Pinus contorta forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its

  2. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    Science.gov (United States)

    Agne, Michelle C; Shaw, David C; Woolley, Travis J; Queijeiro-Bolaños, Mónica E

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum) also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its potential to

  3. Evaluating the role of cutting treatments, fire and soil seed banks in an experimental framework in ponderosa pine forests of the Black Hills, South Dakota

    Science.gov (United States)

    Cody L. Wienk; Carolyn Hull Sieg; Guy R. McPherson

    2004-01-01

    Pinus ponderosa Laws. (ponderosa pine) forests have changed considerably during the past century, partly because recurrent fires have been absent for a century or more. A number of studies have explored the influence of timber harvest or burning on understory production in ponderosa pine forests, but study designs incorporating cutting and prescribed...

  4. Seed origin and size of ponderosa pine planting stock grown at several California nurseries

    Science.gov (United States)

    Frank J. Baron; Gilbert H. Schubert

    1963-01-01

    Ponderosa pine planting stock (1-0 and 2-0) grown from five different seed collection zones in the California pine region differed noticeably in size. On the west side of the Sierra Nevada, seeds from zones above 4,000 feet yielded smaller seedlings than those from lower zones, but larger seedlings than those from east-side sources. Average dimensions (seedling weight...

  5. Local and regional variation in the monoterpenes of ponderosa pine wood oleoresin

    Science.gov (United States)

    R.H. Smith; R.L. Peloquin; P.C. Passof

    1969-01-01

    A gas chromatographic analysis of the mono-terpenes of 927 ponderosa pines, representing to some degree a major portion of the species' range, showed considerable local and regional diversity in composition. Five major monoterpenes— α-pinene, β-pinene, 3-carene, myrcene, and limonene—were analyzed. There is some evidence to support the...

  6. Eighty-eight years of change in a managed ponderosa pine forest

    Science.gov (United States)

    Helen Y. Smith; Stephen F. Arno

    1999-01-01

    This publication gives an overview of structural and other ecological changes associated with forest management and fire suppression since the early 1900's in a ponderosa pine forest, the most widespread forest type in the Western United States. Three sources of information are presented: (1) changes seen in a series of repeat photographs taken between 1909 and...

  7. Understory vegetation response to mechanical mastication and other fuels treatments in a ponderosa pine forest

    Science.gov (United States)

    Jeffrey M. Kane; J. Morgan Varner; Eric E. Knapp

    2010-01-01

    Questions: What influence does mechanical mastication and other fuel treatments have on: (1) canopy and forest floor response variables that influence understory plant development; (2) initial understory vegetation cover, diversity, and composition; and (3) shrub and non-native species density in a secondgrowth ponderosa pine forest....

  8. CORRELATION BETWEEN OZONE EXPOSURE AND VISIBLE FOLIAR INJURY IN PONDEROSA AND JEFFREY PINES. (R825433)

    Science.gov (United States)

    Ozone exposure was related to ozone-induced visible foliar injury in ponderosa and Jeffrey pines growing on the western slopes of the Sierra Nevada Mountains of California. Measurements of ozone exposure, chlorotic mottle and fascicle retention were collected during the years ...

  9. EFFECTS OF CO2 AND O3 IN PONDEROSA PINE PLANT/LITTER/SOIL MESOCOSMS

    Science.gov (United States)

    Forested ecosysems are subjected to interacting conditions whose joint impacts may be quite different from those from single factors. To understand the impacts of CO2 and O3 on forest ecosystems, in April 1998, we initiated a four-year study of a Ponderosa pine seedling/soil/lit...

  10. Response of planted ponderosa pine seedlings to weed control by herbicide in western Montana

    Science.gov (United States)

    Fabian C.C. Uzoh

    1999-01-01

    The effects of competing herbaceous vegetation on the growth of ponderosa pine seedlings with and without herbicide Pronone were characterized in this 1987-1990 study. Study areas were established in 36 plantations across western Montana on Champion International Corporation's timberland (currently owned by Plum Creek Timber Company). The study sites were divided...

  11. Short-term ecological consequences of collaborative restoration treatments in ponderosa pine forests of Colorado

    Science.gov (United States)

    Jennifer S. Briggs; Paula J. Fornwalt; Jonas A. Feinstein

    2017-01-01

    Ecological restoration treatments are being implemented at an increasing rate in ponderosa pine and other dry conifer forests across the western United States, via the USDA Forest Service’s Collaborative Forest Landscape Restoration (CFLR) program. In this program, collaborative stakeholder groups work with National Forests (NFs) to adaptively implement and monitor...

  12. PARTITIONING OF WATER FLUX IN A SIERRA NEVADA PONDEROSA PINE PLANTATION. (R826601)

    Science.gov (United States)

    The weather patterns of the west side of the Sierra Nevada Mountains (cold, wet winters and hot, dry summers) strongly influence how water is partitioned between transpiration and evaporation and result in a specific strategy of water use by ponderosa pine trees (Pinus pond...

  13. Modeling precipitation-runoff relationships to determine water yield from a ponderosa pine forest watershed

    Science.gov (United States)

    Assefa S. Desta

    2006-01-01

    A stochastic precipitation-runoff modeling is used to estimate a cold and warm-seasons water yield from a ponderosa pine forested watershed in the north-central Arizona. The model consists of two parts namely, simulation of the temporal and spatial distribution of precipitation using a stochastic, event-based approach and estimation of water yield from the watershed...

  14. Summary (Songbird ecology in southwestern ponderosa pine forests: A literature review)

    Science.gov (United States)

    William M. Block; Deborah M. Finch; Joseph L. Ganey; William H. Moir

    1997-01-01

    Most ornithological studies in Southwestern ponderosa pine forests have yielded results that are applicable only to the specific location and particular conditions of the study areas (for example, Green 1979 and Hurlbert 1984). In addition, varying interpretation of similar study results by investigators has limited our ability to extend or synthesize research results...

  15. Changes in canopy fuels and fire behavior after ponderosa pine restoration treatments: A landscape perspective

    Science.gov (United States)

    J. P. Roccaforte; P. Z. Fule

    2008-01-01

    (Please note, this is an abstract only) We modeled crown fire behavior and assessed changes in canopy fuels before and after the implementation of restoration treatments in a ponderosa pine landscape at Mt. Trumbull, Arizona. We measured 117 permanent plots before (1996/1997) and after (2003) thinning and burning treatments. The plots are evenly distributed across the...

  16. Phytotoxic grass residues reduce germination and initial root growth of ponderosa pine

    Science.gov (United States)

    W. J. Rietveld

    1975-01-01

    Extracts of green foliage of Arizona fescue and mountain muhly significantly reduced germination of ponderosa pine seeds, and retarded speed of elongation and mean radicle length. Three possible routes of release of the inhibitor were investigated: (1) leaching from live foliage, (2) root exudation, and (3) overwinter leaching from dead residues. The principal route...

  17. Impact of a Mountain Pine Beetle Outbreak on Young Lodgepole Pine Stands in Central British Columbia

    OpenAIRE

    Dhar, Amalesh; Balliet, Nicole; Runzer, Kyle; Hawkins, Christopher

    2015-01-01

    The current mountain pine beetle (MPB) (Dendroctonous ponderosae Hopkins) epidemic has severely affected pine forests of Western Canada and killed millions of hectares of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forest. Generally, MPB attack larger and older (diameter > 20 cm or >60 years of age) trees, but the current epidemic extends this limit with attacks on even younger and smaller trees. The study’s aim was to investigate the extent of MPB attack in y...

  18. The Effect of Water Limitation on Volatile Emission, Tree Defense Response, and Brood Success of Dendroctonus ponderosae in Two Pine Hosts, Lodgepole, and Jack Pine

    OpenAIRE

    Lusebrink, Inka; Erbilgin, Nadir; Evenden, Maya L.

    2016-01-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae) has recently expanded its range from lodgepole pine forest into the lodgepole × jack pine hybrid zone in central Alberta, within which it has attacked pure jack pine. This study tested the effects of water limitation on tree defense response of mature lodgepole and jack pine (Pinus contorta and Pinus banksiana) trees in the field. Tree defense response was initiated by inoculation of trees with the MPB-associated fungus Grosmannia clavig...

  19. Response of brown-headed cowbirds and three host species to thinning treatments in low-elevation ponderosa pine forests along the northern Colorado Front Range

    Science.gov (United States)

    Keeley, W.H.; Germaine, Stephen S.; Stanley, Thomas R.; Spaulding, Sarah A.; Wanner, C.E.

    2013-01-01

    Thinning ponderosa pine (Pinus ponderosa) forests to achieve desired ecological conditions remains a priority in the North American west. In addition to reducing the risk of high-severity wildfires in unwanted areas, stand thinning may increase wildlife and plant diversity and provide increased opportunity for seedling recruitment. We initiated conservative (i.e. minimal removal of trees) ponderosa stand thinning treatments with the goals of reducing fire risk and improving habitat conditions for native wildlife and flora. We then compared site occupancy of brown-headed cowbirds (Molothrus ater), chipping sparrows (Spizella passerina), plumbeous vireos (Vireo plumbeus), and western wood-pewees (Contopus sordidulus) in thinned and unthinned (i.e., control) forest stands from 2007 to 2009. Survey stations located in thinned stands had 64% fewer trees/ha, 25% less canopy cover, and 23% less basal area than stations in control stands. Occupancy by all three host species was negatively associated with tree density, suggesting that these species respond favorably to forest thinning treatments in ponderosa pine forests. We also encountered plumbeous vireos more frequently in plots closer to an ecotonal (forest/grassland) edge, an association that may increase their susceptibility to edge-specialist, brood parasites like brown-headed cowbirds. Occupancy of brown-headed cowbirds was not related to forest metrics but was related to occupancy by plumbeous vireos and the other host species in aggregate, supporting previous reports on the affiliation between these species. Forest management practices that promote heterogeneity in forest stand structure may benefit songbird populations in our area, but these treatments may also confer costs associated with increased cowbird occupancy. Further research is required to understand more on the complex relationships between occupancy of cowbirds and host species, and between cowbird occupancy and realized rates of nest parasitism.

  20. Changes in forest structure since 1860 in ponderosa pine dominated forests in the Colorado and Wyoming Front Range, USA

    Science.gov (United States)

    Mike A. Battaglia; Benjamin Gannon; Peter M. Brown; Paula J. Fornwalt; Antony S. Cheng; Laurie S. Huckaby

    2018-01-01

    Management practices since the late 19th century, including fire exclusion and harvesting, have altered the structure of ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) dominated forests across the western United States. These structural changes have the potential to contribute to uncharacteristic wildfire behavior and effects. Locally-...

  1. Role of selection versus historical isolation in racial differentiation of ponderosa pine in southern Oregon: an investigation of alternative hypotheses.

    Science.gov (United States)

    Frank C. Sorensen; Nancy L. Mandel; Jan E. Aagaard

    2001-01-01

    Continuous populations identified as Pacific and North Plateau races of ponderosa pine (Pinus ponderosa P. Laws. ex C. Laws.) are parapatric along the crest of the Cascade Range in southern Oregon. A 3-year common-garden study of bud phenology and seedling vigor was performed to estimate the nature and magnitude of differentiation between races, to...

  2. Influence of elevation on bark beetle (Coleoptera: Curculionidae, Scolytinae) community structure and flight periodicity in ponderosa pine forests of Arizona

    Science.gov (United States)

    Kelly K. Williams; Joel D. McMillin; Tom E. DeGomez; Karen M. Clancy; Andy Miller

    2008-01-01

    We examined abundance and flight periodicity of five Ips and six Dendroctonus species (Coleoptera: Curculionidae, Scolytinae) among three different elevation bands in ponderosa pine (Pinus ponderosa Douglas ex. Lawson) forests of northcentral Arizona. Bark beetle populations were monitored at 10 sites in each of three elevation...

  3. 3-PG simulations of young ponderosa pine plantations under varied management intensity: why do they grow so differently?

    Science.gov (United States)

    Liang Wei; Marshall John; Jianwei Zhang; Hang Zhou; Robert Powers

    2014-01-01

    Models can be powerful tools for estimating forest productivity and guiding forest management, but their credibility and complexity are often an issue for forest managers. We parameterized a process-based forest growth model, 3-PG (Physiological Principles Predicting Growth), to simulate growth of ponderosa pine (Pinus ponderosa) plantations in...

  4. Effects of low intensity prescribed fires on ponderosa pine forests in wilderness areas of Zion National Park, Utah

    Science.gov (United States)

    Henry V. Bastian

    2001-01-01

    Vegetation and fuel loading plots were monitored and sampled in wilderness areas treated with prescribed fire. Changes in ponderosa pine (Pinus ponderosa) forest structure tree species and fuel loading are presented. Plots were randomly stratified and established in burn units in 1995. Preliminary analysis of nine plots 2 years after burning show litter was reduced 54....

  5. A field guide to predict delayed mortality of fire-damaged ponderosa pine: application and validation of the Malheur model.

    Science.gov (United States)

    Walter G. Thies; Douglas J. Westlind; Mark Loewen; Greg. Brenner

    2008-01-01

    The Malheur model for fire-caused delayed mortality is presented as an easily interpreted graph (mortality-probability calculator) as part of a one-page field guide that allows the user to determine postfire probability of mortality for ponderosa pine (Pinus ponderosa Dougl. ex Laws.). Following both prescribed burns and wildfires, managers need...

  6. Effects of wildfire on densities of secondary cavity-nesting birds in ponderosa pine forests of northern Arizona

    Science.gov (United States)

    Jill K. Dwyer; William M. Block

    2000-01-01

    Many catastrophic wildfires burned throughout forests in Arizona during the spring and summer of 1996 owing to severely dry conditions. One result of these fires was a loss of preexisting tree cavities for reproduction. In ponderosa pine (Pinus ponderosa) forests most cavities are found in dead trees; therefore, snags are a very important habitat...

  7. INTERACTIVE EFFECTS OF CO2 AND O3 ON A PONDEROSA PINE PLANT/LITTER/SOIL MESOCOSM

    Science.gov (United States)

    To study individual and combined impacts of two important atmospheric trace gases, CO2 and O3, on C and N cycling in forest ecosystems; a four-year experiment using a small-scale ponderosa pine (Pinus ponderosa Laws.) seedling/soil/litter system was initiated in April, 1998. Th...

  8. Understory vegetation response after 30 years of interval prescribed burning in two ponderosa pine sites in northern Arizona, USA

    Science.gov (United States)

    Catherine A. Scudieri; Carolyn Hull Sieg; Sally M. Haase; Andrea E. Thode; Stephen S. Sackett

    2010-01-01

    Southwestern USA ponderosa pine (Pinus ponderosa C. Lawson var. scopulorum Engelm.) forests evolved with frequent surface fires and have changed dramatically over the last century. Overstory tree density has sharply increased while abundance of understory vegetation has declined primarily due to the near cessation of fires. We...

  9. Stomata open at night in pole-sized and mature ponderosa pine: implications for O{sub 3} exposure metrics

    Energy Technology Data Exchange (ETDEWEB)

    Grulke, N. E.; Alonso, R.; Nguyen, T.; Dobrowolski, W. [USDA Forest Service, Pacific Southwest Station, Riverside, CA (United States); Cascio, C. [University of Florence, Firenze (Italy)

    2004-09-01

    Nighttime stomatal behaviour in two tree size stands of ponderosa pine are described. Ponderosa pine is one of the most ozone-sensitive conifers in western North America. The study involved measurement of time required to reach equilibrium in response to small increases in low irradiances at sites differing in environmental stressors. The contribution of nighttime ozone uptake to total daily ozone uptake in early and later summer was also investigated. Nighttime stomata conductance ranged between one tenth and one fifth that of maximum day-time values. Pole-size trees (i.e. less than 40 years old) showed greater ozone conductance than mature trees (i.e. over 250 years old). In June, nighttime ozone uptake accounted for 9, 5, and 3 per cent of the total daily ozone uptake of pole-sized trees. In late summer, ozone uptake at night was less than two percent of daily uptake at all sites. It is suspected that nighttime uptake of oxidants may have harmful physiological effects, such as contributing to the declining health of forest trees, owing to the fact that oxidants absorbed at night are not detoxified as well during the day. 67 refs.,1 tab., 8 figs.

  10. Exploring climate niches of ponderosa pine (Pinus ponderosa Douglas ex Lawson) haplotypes in the western United States: Implications for evolutionary history and conservation

    Science.gov (United States)

    Shinneman, Douglas; Means, Robert E.; Potter, Kevin M.; Hipkins, Valerie D.

    2016-01-01

    Ponderosa pine (Pinus ponderosa Douglas ex Lawson) occupies montane environments throughout western North America, where it is both an ecologically and economically important tree species. A recent study using mitochondrial DNA analysis demonstrated substantial genetic variation among ponderosa pine populations in the western U.S., identifying 10 haplotypes with unique evolutionary lineages that generally correspond spatially with distributions of the Pacific (P. p. var. ponderosa) and Rocky Mountain (P. p. var. scopulorum) varieties. To elucidate the role of climate in shaping the phylogeographic history of ponderosa pine, we used nonparametric multiplicative regression to develop predictive climate niche models for two varieties and 10 haplotypes and to hindcast potential distribution of the varieties during the last glacial maximum (LGM), ~22,000 yr BP. Our climate niche models performed well for the varieties, but haplotype models were constrained in some cases by small datasets and unmeasured microclimate influences. The models suggest strong relationships between genetic lineages and climate. Particularly evident was the role of seasonal precipitation balance in most models, with winter- and summer-dominated precipitation regimes strongly associated with P. p. vars. ponderosa and scopulorum, respectively. Indeed, where present-day climate niches overlap between the varieties, introgression of two haplotypes also occurs along a steep clinal divide in western Montana. Reconstructed climate niches for the LGM suggest potentially suitable climate existed for the Pacific variety in the California Floristic province, the Great Basin, and Arizona highlands, while suitable climate for the Rocky Mountain variety may have existed across the southwestern interior highlands. These findings underscore potentially unique phylogeographic origins of modern ponderosa pine evolutionary lineages, including potential adaptations to Pleistocene climates associated with

  11. Exploring Climate Niches of Ponderosa Pine (Pinus ponderosa Douglas ex Lawson) Haplotypes in the Western United States: Implications for Evolutionary History and Conservation.

    Science.gov (United States)

    Shinneman, Douglas J; Means, Robert E; Potter, Kevin M; Hipkins, Valerie D

    2016-01-01

    Ponderosa pine (Pinus ponderosa Douglas ex Lawson) occupies montane environments throughout western North America, where it is both an ecologically and economically important tree species. A recent study using mitochondrial DNA analysis demonstrated substantial genetic variation among ponderosa pine populations in the western U.S., identifying 10 haplotypes with unique evolutionary lineages that generally correspond spatially with distributions of the Pacific (P. p. var. ponderosa) and Rocky Mountain (P. p. var. scopulorum) varieties. To elucidate the role of climate in shaping the phylogeographic history of ponderosa pine, we used nonparametric multiplicative regression to develop predictive climate niche models for two varieties and 10 haplotypes and to hindcast potential distribution of the varieties during the last glacial maximum (LGM), ~22,000 yr BP. Our climate niche models performed well for the varieties, but haplotype models were constrained in some cases by small datasets and unmeasured microclimate influences. The models suggest strong relationships between genetic lineages and climate. Particularly evident was the role of seasonal precipitation balance in most models, with winter- and summer-dominated precipitation regimes strongly associated with P. p. vars. ponderosa and scopulorum, respectively. Indeed, where present-day climate niches overlap between the varieties, introgression of two haplotypes also occurs along a steep clinal divide in western Montana. Reconstructed climate niches for the LGM suggest potentially suitable climate existed for the Pacific variety in the California Floristic province, the Great Basin, and Arizona highlands, while suitable climate for the Rocky Mountain variety may have existed across the southwestern interior highlands. These findings underscore potentially unique phylogeographic origins of modern ponderosa pine evolutionary lineages, including potential adaptations to Pleistocene climates associated with discrete

  12. Exploring Climate Niches of Ponderosa Pine (Pinus ponderosa Douglas ex Lawson Haplotypes in the Western United States: Implications for Evolutionary History and Conservation.

    Directory of Open Access Journals (Sweden)

    Douglas J Shinneman

    Full Text Available Ponderosa pine (Pinus ponderosa Douglas ex Lawson occupies montane environments throughout western North America, where it is both an ecologically and economically important tree species. A recent study using mitochondrial DNA analysis demonstrated substantial genetic variation among ponderosa pine populations in the western U.S., identifying 10 haplotypes with unique evolutionary lineages that generally correspond spatially with distributions of the Pacific (P. p. var. ponderosa and Rocky Mountain (P. p. var. scopulorum varieties. To elucidate the role of climate in shaping the phylogeographic history of ponderosa pine, we used nonparametric multiplicative regression to develop predictive climate niche models for two varieties and 10 haplotypes and to hindcast potential distribution of the varieties during the last glacial maximum (LGM, ~22,000 yr BP. Our climate niche models performed well for the varieties, but haplotype models were constrained in some cases by small datasets and unmeasured microclimate influences. The models suggest strong relationships between genetic lineages and climate. Particularly evident was the role of seasonal precipitation balance in most models, with winter- and summer-dominated precipitation regimes strongly associated with P. p. vars. ponderosa and scopulorum, respectively. Indeed, where present-day climate niches overlap between the varieties, introgression of two haplotypes also occurs along a steep clinal divide in western Montana. Reconstructed climate niches for the LGM suggest potentially suitable climate existed for the Pacific variety in the California Floristic province, the Great Basin, and Arizona highlands, while suitable climate for the Rocky Mountain variety may have existed across the southwestern interior highlands. These findings underscore potentially unique phylogeographic origins of modern ponderosa pine evolutionary lineages, including potential adaptations to Pleistocene climates associated

  13. Decadal Recruitment and Mortality of Ponderosa pine Predicted for the 21st Century Under five Downscaled Climate Change Scenarios

    Science.gov (United States)

    Ironside, K. E.; Cole, K. L.; Eischeid, J. K.; Garfin, G. M.; Shaw, J. D.; Cobb, N. S.

    2008-12-01

    Ponderosa pine (Pinus ponderosa var. scopulorum) is the dominant conifer in higher elevation regions of the southwestern United States. Because this species is so prominent, southwestern montane ecosystems will be significantly altered if this species is strongly affected by future climate changes. These changes could be highly challenging for land management agencies. In order to model the consequences of future climates, 20th Century recruitment events and mortality for ponderosa pine were characterized using measures of seasonal water balance (precipitation - potential evapotranspiration). These relationships, assuming they will remain unchanged, were then used to predict 21st Century changes in ponderosa pine occurrence in the southwest. Twenty-one AR4 IPCC General Circulation Model (GCM) A1B simulation results were ranked on their ability to simulate the later 20th Century (1950-2000 AD) precipitation seasonality, spatial patterns, and quantity in the western United States. Among the top ranked GCMs, five were selected for downscaling to a 4 km grid that represented a range in predictions in terms of changes in water balance. Predicted decadal changes in southwestern ponderosa pine for the 21st Century for these five climate change scenarios were calculated using a multiple quadratic logistic regression model. Similar models of other western tree species (Pinus edulis, Yucca brevifolia) predicted severe contractions, especially in the southern half of their ranges. However, the results for Ponderosa pine suggested future expansions throughout its range to both higher and lower elevations, as well as very significant expansions northward.

  14. Mountain pine beetle selectivity in old-growth ponderosa pine forests, Montana, USA.

    Science.gov (United States)

    Knapp, Paul A; Soulé, Peter T; Maxwell, Justin T

    2013-05-01

    A historically unprecedented mountain pine beetle (MPB) outbreak affected western Montana during the past decade. We examined radial growth rates (AD 1860-2007/8) of co-occurring mature healthy and MPB-infected ponderosa pine trees collected at two sites (Cabin Gulch and Kitchen Gulch) in western Montana and: (1) compared basal area increment (BAI) values within populations and between sites; (2) used carbon isotope analysis to calculate intrinsic water-use efficiency (iWUE) at Cabin Gulch; and (3) compared climate-growth responses using a suite of monthly climatic variables. BAI values within populations and between sites were similar until the last 20-30 years, at which point the visually healthy populations had consistently higher BAI values (22-34%) than the MPB-infected trees. These results suggest that growth rates two-three decades prior to the current outbreak diverged between our selected populations, with the slower-growing trees being more vulnerable to beetle infestation. Both samples from Cabin Gulch experienced upward trends in iWUE, with significant regime shifts toward higher iWUE beginning in 1955-59 for the visually healthy trees and 1960-64 for the MPB-infected trees. Drought tolerance also varied between the two populations with the visually healthy trees having higher growth rates than MPB-infected trees prior to infection during a multi-decadal period of drying summertime conditions. Intrinsic water-use efficiency significantly increased for both populations during the past 150 years, but there were no significant differences between the visually healthy and MPB-infected chronologies.

  15. Insight into the hydraulics and resilience of Ponderosa pine seedlings using a mechanistic ecohydrologic model

    Science.gov (United States)

    Maneta, M. P.; Simeone, C.; Dobrowski, S.; Holden, Z.; Sapes, G.; Sala, A.; Begueria, S.

    2017-12-01

    In semiarid regions, drought-induced seedling mortality is considered to be caused by failure in the tree hydraulic column. Understanding the mechanisms that cause hydraulic failure and death in seedlings is important, among other things, to diagnose where some tree species may fail to regenerate, triggering demographic imbalances in the forest that could result in climate-driven shifts of tree species. Ponderosa pine is a common lower tree line species in the western US. Seedlings of ponderosa pine are often subject to low soil water potentials, which require lower water potentials in the xylem and leaves to maintain the negative pressure gradient that drives water upward. The resilience of the hydraulic column to hydraulic tension is species dependent, but from greenhouse experiments, we have identified general tension thresholds beyond which loss of xylem conductivity becomes critical, and mortality in Ponderosa pine seedlings start to occur. We describe this hydraulic behavior of plants using a mechanistic soil-vegetation-atmosphere transfer model. Before we use this models to understand water-stress induced seedling mortality at the landscape scale, we perform a modeling analysis of the dynamics of soil moisture, transpiration, leaf water potential and loss of plant water conductivity using detailed data from our green house experiments. The analysis is done using a spatially distributed model that simulates water fluxes, energy exchanges and water potentials in the soil-vegetation-atmosphere continuum. Plant hydraulic and physiological parameters of this model were calibrated using Monte Carlo methods against information on soil moisture, soil hydraulic potential, transpiration, leaf water potential and percent loss of conductivity in the xylem. This analysis permits us to construct a full portrait of the parameter space for Ponderosa pine seedling and generate posterior predictive distributions of tree response to understand the sensitivity of transpiration

  16. Effect of dietary protein level and quebracho tannin on consumption of pine needles (Pinus ponderosa) by beef cows

    Science.gov (United States)

    Ponderosa pine trees occupy over 15 million hectares of rangeland in western North America. Pregnant cows often consume pine needles (PN), and subsequently abort. The protein-to-energy ratio may be important in the ability of cattle to tolerate dietary terpenes. Tannins often co-occur with terpenes ...

  17. A decadal glimpse on climate and burn severity influences on ponderosa pine post-fire recovery

    Science.gov (United States)

    Newingham, B. A.; Hudak, A. T.; Bright, B. C.; Smith, A.; Khalyani, A. H.

    2016-12-01

    Climate change is predicted to affect plants at the margins of their distribution. Thus, ecosystem recovery after fire is likely to vary with climate and may be slowest in drier and hotter areas. However, fire regime characteristics, including burn severity, may also affect vegetation recovery. We assessed vegetation recovery one and 9-15 years post-fire in North American ponderosa pine ecosystems distributed across climate and burn severity gradients. Using climate predictors derived from downscaled 1993-2011 climate normals, we predicted vegetation recovery as indicated by Normalized Burn Ratio derived from 1984-2012 Landsat time series imagery. Additionally, we collected field vegetation measurements to examine local topographic controls on burn severity and post-fire vegetation recovery. At a regional scale, we hypothesized a positive relationship between precipitation and recovery time and a negative relationship between temperature and recovery time. At the local scale, we hypothesized southern aspects to recovery slower than northern aspects. We also predicted higher burn severity to slow recovery. Field data found attenuated ponderosa pine recovery in hotter and drier regions across all burn severity classes. We concluded that downscaled climate data and Landsat imagery collected at commensurate scales may provide insight into climate effects on post-fire vegetation recovery relevant to ponderosa pine forest managers.

  18. Rapid Induction of Multiple Terpenoid Groups by Ponderosa Pine in Response to Bark Beetle-Associated Fungi.

    Science.gov (United States)

    Keefover-Ring, Ken; Trowbridge, Amy; Mason, Charles J; Raffa, Kenneth F

    2016-01-01

    Ponderosa pine (Pinus ponderosa) is a major and widely distributed component of conifer biomes in western North America and provides substantial ecological and economic benefits. This tree is exposed to several tree-killing bark beetle-microbial complexes, including the mountain pine beetle (Dendroctonus ponderosae) and the phytopathogenic fungus Grosmannia clavigera that it vectors, which are among the most important. Induced responses play a crucial role in conifer defenses, yet these have not been reported in ponderosa pine. We compared concentrations of terpenes and a phenylpropanoid, two phytochemical classes with strong effects against bark beetles and their symbionts, in constitutive phloem tissue and in tissue following mechanical wounding or simulated D. ponderosae attack (mechanical wounding plus inoculation with G. clavigera). We also tested whether potential induced responses were localized or systemic. Ponderosa pines showed pronounced induced defenses to inoculation, increasing their total phloem concentrations of monoterpenes 22.3-fold, sesquiterpenes 56.7-fold, and diterpenes 34.8-fold within 17 days. In contrast, responses to mechanical wounding alone were only 5.2, 11.3, and 7.7-fold, respectively. Likewise, the phenylpropanoid estragole (4-allyanisole) rose to 19.1-fold constitutive levels after simulated attack but only 4.4-fold after mechanical wounding. Overall, we found no evidence of systemic induction after 17 days, which spans most of this herbivore's narrow peak attack period, as significant quantitative and compositional changes within and between terpenoid groups were localized to the wound site. Implications to the less frequent exploitation of ponderosa than lodgepole pine by D. ponderosae, and potential advantages of rapid localized over long-term systemic responses in this system, are discussed.

  19. Effects of seeding ryegrass (Lolium multiflorum) on vegetation recovery following fire in a ponderosa pine (Pinus ponderosa) forest

    Science.gov (United States)

    Barclay, Angela D.; Betancourt, Julio L.; Allen, Craig D.

    2004-01-01

    Forty-nine vegetation transects were measured in 1997 and 1998 to determine the impact of grass seeding after the 1996 Dome Fire, which burned almost 6900 ha of ponderosa pine (Pinus ponderosa Lawson) forest in the Jemez Mountains of north-central New Mexico. High- and moderate-burned areas in Santa Fe National Forest were seeded with a mixture that included the exotic ryegrass (Lolium multiflorum Lam.). Adjacent burned areas of Bandelier National Monument were not seeded, and were used as a control in the post-seeding study. On the seeded plots, foliar cover of ryegrass declined from 1997 to 1998 due to self-inhibition and/or reduced precipitation from 1997 to 1998. Foliar cover and diversity of native forbs were greater in 1997 than 1998, probably due to a wet growing season in 1997. Cover, species richness, and diversity of native forbs were highest in non-seeded areas of moderate- and high-burn intensities. Regeneration and survivorship of conifer seedlings decreased as ryegrass cover increased, particularly in areas of high-burn intensity. Exotic plant cover, mostly horseweed [Conyza canadensis (L.) Cronq.], increased from 1997 to 1998 in non-seeded areas of moderate- and high-burn intensity. Both the initial success of seeding and the eventual impacts on native vegetation were strongly modulated by climate variability.

  20. Litter and dead wood dynamics in ponderosa pine forests along a 160-year chronosequence.

    Science.gov (United States)

    Hall, S A; Burke, I C; Hobbs, N T

    2006-12-01

    Disturbances such as fire play a key role in controlling ecosystem structure. In fire-prone forests, organic detritus comprises a large pool of carbon and can control the frequency and intensity of fire. The ponderosa pine forests of the Colorado Front Range, USA, where fire has been suppressed for a century, provide an ideal system for studying the long-term dynamics of detrital pools. Our objectives were (1) to quantify the long-term temporal dynamics of detrital pools; and (2) to determine to what extent present stand structure, topography, and soils constrain these dynamics. We collected data on downed dead wood, litter, duff (partially decomposed litter on the forest floor), stand structure, topographic position, and soils for 31 sites along a 160-year chronosequence. We developed a compartment model and parameterized it to describe the temporal trends in the detrital pools. We then developed four sets of statistical models, quantifying the hypothesized relationship between pool size and (1) stand structure, (2) topography, (3) soils variables, and (4) time since fire. We contrasted how much support each hypothesis had in the data using Akaike's Information Criterion (AIC). Time since fire explained 39-80% of the variability in dead wood of different size classes. Pool size increased to a peak as material killed by the fire fell, then decomposed rapidly to a minimum (61-85 years after fire for the different pools). It then increased, presumably as new detritus was produced by the regenerating stand. Litter was most strongly related to canopy cover (r2 = 77%), suggesting that litter fall, rather than decomposition, controls its dynamics. The temporal dynamics of duff were the hardest to predict. Detrital pool sizes were more strongly related to time since fire than to environmental variables. Woody debris peak-to-minimum time was 46-67 years, overlapping the range of historical fire return intervals (1 to > 100 years). Fires may therefore have burned under a

  1. Short-Term Belowground Responses to Thinning and Burning Treatments in Southwestern Ponderosa Pine Forests of the USA

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    Steven T. Overby

    2016-02-01

    Full Text Available Microbial-mediated decomposition and nutrient mineralization are major drivers of forest productivity. As landscape-scale fuel reduction treatments are being implemented throughout the fire-prone western United States of America, it is important to evaluate operationally how these wildfire mitigation treatments alter belowground processes. We quantified these important belowground components before and after management-applied fuel treatments of thinning alone, thinning combined with prescribed fire, and prescribed fire in ponderosa pine (Pinus ponderosa stands at the Southwest Plateau, Fire and Fire Surrogate site, Arizona. Fuel treatments did not alter pH, total carbon and nitrogen (N concentrations, or base cations of the forest floor (O horizon or mineral soil (0–5 cm during this 2-year study. In situ rates of net N mineralization and nitrification in the surface mineral soil (0–15 cm increased 6 months after thinning with prescribed fire treatments; thinning only resulted in net N immobilization. The rates returned to pre-treatment levels after one year. Based on phospholipid fatty acid composition, microbial communities in treated areas were similar to untreated areas (control in the surface organic horizon and mineral soil (0–5 cm after treatments. Soil potential enzyme activities were not significantly altered by any of the three fuel treatments. Our results suggest that a variety of one-time alternative fuel treatments can reduce fire hazard without degrading soil fertility.

  2. Evaluation of funnel traps for characterizing the bark beetle (Coleoptera: Scolytidae) communities in ponderosa pine forests of north-central Arizona.

    Science.gov (United States)

    Hayes, Christopher J; DeGomez, Tom E; Clancy, Karen M; Williams, Kelly K; McMillin, Joel D; Anhold, John A

    2008-08-01

    Lindgren funnel traps baited with aggregation pheromones are widely used to monitor and manage populations of economically important bark beetles (Coleoptera: Scolytidae). This study was designed to advance our understanding of how funnel trap catches assess bark beetle communities and relative abundance of individual species. In the second year (2005) of a 3-yr study of the bark beetle community structure in north-central Arizona pine (Pinus spp.) forests, we collected data on stand structure, site conditions, and local bark beetle-induced tree mortality at each trap site. We also collected samples of bark from infested (brood) trees near trap sites to identify and determine the population density of bark beetles that were attacking ponderosa pine, Pinus ponderosa Douglas ex Lawson, in the area surrounding the traps. Multiple regression models indicated that the number of Dendroctonus and Ips beetles captured in 2005 was inversely related to elevation of the trap site, and positively associated with the amount of ponderosa pine in the stand surrounding the site. Traps located closer to brood trees also captured more beetles. The relationship between trap catches and host tree mortality was weak and inconsistent in forest stands surrounding the funnel traps, suggesting that trap catches do not provide a good estimate of local beetle-induced tree mortality. However, pheromone-baited funnel trap data and data from gallery identification in bark samples produced statistically similar relative abundance profiles for the five species of bark beetles that we examined, indicating that funnel trap data provided a good assessment of species presence and relative abundance.

  3. Overstory Tree Mortality in Ponderosa Pine and Spruce-Fir Ecosystems Following a Drought in Northern New Mexico

    Directory of Open Access Journals (Sweden)

    Brian P. Oswald

    2016-10-01

    Full Text Available Drought-caused tree dieback is an issue around the world as climates change and many areas become dryer and hotter. A drought from 1998–2004 resulted in a significant tree dieback event in many of the wooded areas in portions of the Jemez Mountains and the adjacent Pajarito Plateau in northern New Mexico. The objectives of this study were to evaluate and quantify the differences in tree mortality before and after a recent drought in ponderosa pine and spruce-fir ecosystems, and to assess the effect of mechanical thinning on ponderosa pine mortality. Significant increases in mortality were observed in the unthinned ponderosa pine ecosystem. Mortality varied significantly between species and within size classes. Mechanical thinning of ponderosa pines reduced overstory mortality to non-significant levels. A lack of rainfall, snowfall, and increases in daily minimum temperature contributed most to the mortality. Adaptive management, including the use of thinning activities, appear to moderate the impact of climate change on ponderosa pine forests in this region, increasing the long-term health of the ecosystem. The impact of climate change on the spruce-fir ecosystems may accelerate successional changes.

  4. Southern pine beetle in loblolly pine: simulating within stand interactions using the process model SPBLOBTHIN

    Science.gov (United States)

    Brian Strom; J. R. Meeker; J. Bishir; James Roberds; X. Wan

    2016-01-01

    Pine stand density is a key determinant of damage resulting from attacks by the southern pine beetle (SPB, Dendroctonus frontalis Zimm.). High-density stands of maturing loblolly pine (Pinus taeda L.) are at high risk for losses to SPB, and reducing stand density is the primary tool available to forest managers for preventing and mitigating damage. Field studies are...

  5. Effect of ponderosa pine needle litter on grass seedling survival.

    Science.gov (United States)

    Burt R. McConnell; Justin G. Smith

    1971-01-01

    Hard fescue survival rates were followed for 6 years on four different pine needle treatment plots. Needle litter had a significant effect on initial survival of fescue seedlings, but subsequent losses undoubtedly resulted from the interaction of many factors.

  6. Short-term ecological consequences of collaborative restoration treatments in ponderosa pine forests of Colorado

    Science.gov (United States)

    Briggs, Jenny S.; Fornwalt, Paula J.; Feinstein, Jonas A.

    2017-01-01

    Ecological restoration treatments are being implemented at an increasing rate in ponderosa pine and other dry conifer forests across the western United States, via the USDA Forest Service’s Collaborative Forest Landscape Restoration (CFLR) program. In this program, collaborative stakeholder groups work with National Forests (NFs) to adaptively implement and monitor ecological restoration treatments intended to offset the effects of many decades of anthropogenic stressors. We initiated a novel study to expand the scope of treatment effectiveness monitoring efforts in one of the first CFLR landscapes, Colorado’s Front Range. We used a Before/After/Control/Impact framework to evaluate the short-term consequences of treatments on numerous ecological properties. We collected pre-treatment and one year post-treatment data on NF and partner agencies’ lands, in 66 plots distributed across seven treatment units and nearby untreated areas. Our results reflected progress toward several treatment objectives: treated areas had lower tree density and basal area, greater openness, no increase in exotic understory plants, no decrease in native understory plants, and no decrease in use by tree squirrels and ungulates. However, some findings suggested the need for adaptive modification of both treatment prescriptions and monitoring protocols: treatments did not promote heterogeneity of stand structure, and monitoring methods may not have been robust enough to detect changes in surface fuels. Our study highlights both the effective aspects of these restoration treatments, and the importance of initiating and continuing collaborative science-based monitoring to improve the outcomes of broad-scale forest restoration efforts.

  7. Effects of ozone exposures on epicuticular wax of ponderosa pine needles

    International Nuclear Information System (INIS)

    Bytnerowicz, A.; Turunen, M.

    1994-01-01

    Two-year-old ponderosa pine (Pinus ponderosa L.) seedlings were exposed during the 1989 and 1990 growing seasons to ozone in open-top chambers placed in a forested location at Shirley Meadow, Greenhorn Mountain Range, Sierra Nevada. The ozone treatments were as follows: charcoal-filtered air (CF); charcoal-filtered air with addition of ambient concentrations of ozone (CF + O 3 ); and charcoal-filtered air with addition of doubled concentrations of ozone (CF + 2 x O 3 ). Ozone effects on ponderosa pine seedlings progressed and accumulated over two seasons of exposure. Throughout the first season, increased visible injury and accelerated senescence of the foliage were noted. Subsequently, during the second season of ozone exposure, various physiological and biochemical changes in the foliage took place. All these changes led to reduced growth and biomass of the seedlings. Epistomatal waxes of needles from the CA + 2 x O 3 treatment had an occluded appearance. This phenomenon may be caused by earlier phenological development of needles from the high-ozone treatments and disturbed development and synthesis of waxes. It may also be caused by chemical degradation of waxes by exposures to high ozone concentrations. (orig.)

  8. Importance of resin ducts in reducing ponderosa pine mortality from bark beetle attack.

    Science.gov (United States)

    Kane, Jeffrey M; Kolb, Thomas E

    2010-11-01

    The relative importance of growth and defense to tree mortality during drought and bark beetle attacks is poorly understood. We addressed this issue by comparing growth and defense characteristics between 25 pairs of ponderosa pine (Pinus ponderosa) trees that survived and trees that died from drought-associated bark beetle attacks in forests of northern Arizona, USA. The three major findings of our research were: (1) xylem resin ducts in live trees were >10% larger (diameter), >25% denser (no. of resin ducts mm(-2)), and composed >50% more area per unit ring growth than dead trees; (2) measures of defense, such as resin duct production (no. of resin ducts year(-1)) and the proportion of xylem ring area to resin ducts, not growth, were the best model parameters of ponderosa pine mortality; and (3) most correlations between annual variation in growth and resin duct characteristics were positive suggesting that conditions conducive to growth also increase resin duct production. Our results suggest that trees that survive drought and subsequent bark beetle attacks invest more carbon in resin defense than trees that die, and that carbon allocation to resin ducts is a more important determinant of tree mortality than allocation to radial growth.

  9. Changes in the rumen bacterial microbiome of cattle exposed to ponderosa pine needles.

    Science.gov (United States)

    Welch, K D; Stonecipher, C A; Gardner, D R; Cook, D; Pfister, J A

    2017-05-01

    Consumption of ponderosa pine needles, as well as needles and bark from a number of other trees, can cause abortions in cattle. The abortifacient compounds in these trees are labdane resin acids, including isocupressic acid and agathic acid. Previous research has demonstrated that cattle conditioned to pine needles metabolize the labdane resin acids more quickly than naïve cattle. The results from that study indicated that changes had occurred in the rumen of conditioned cattle. Therefore, in this study, the changes that occurred in the rumen bacterial microflora of cattle during exposure to ponderosa pine needles were evaluated. Cattle were dosed with ground pine needles twice daily for 7 d. Rumen samples were collected on d 0, 3, 7, and 14 (7 d after treatment stopped) and ruminal bacterial microbiome analyses were performed. There were 372 different genera of bacteria identified in the rumen samples. Principal coordinate analysis indicated that there was a significant difference in the rumen bacterial composition between the time points. There were 18 genera that increased in abundance from d 0 to d 7. Twenty three genera decreased in abundance from d 0 to d 7. The results from this study demonstrated that exposure of cattle to pine needles caused a clear shift in the rumen microbiome composition. In general, this shift lasted less than 1 wk post exposure, which indicates that any prophylactic treatment to manipulate the ruminal metabolism of the abortifacient compounds in pine needles would need to be continuously administered to maintain the necessary microbial composition in the rumen.

  10. Analytical Modelling of Canopy Interception Loss from a Juvenile Lodgepole Pine (Pinus contorta var. latifolia) Stand

    Science.gov (United States)

    Carlyle-Moses, D. E.; Lishman, C. E.

    2015-12-01

    In the central interior of British Columbia (BC), Canada, the mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB) has severely affected the majority of pine species in the region, especially lodgepole pine (Pinus contorta Douglas ex Louden var. latifolia Engelm. ex S. Watson). The loss of mature lodgepole pine stands, including those lost to salvage logging, has resulted in an increase in the number of juvenile pine stands in the interior of BC through planting and natural regrowth. With this change from mature forests to juvenile forests at such a large spatial scale, the water balance of impacted areas may be altered, although the magnitude of such change is uncertain. Previous studies of rainfall partitioning by lodgepole pine and lodgepole pine dominated canopies have focused on mature stands. Thus, rainfall, throughfall and stemflow were measured and canopy interception loss was derived during the growing season of 2010 in a juvenile lodgepole pine dominated stand located approximately 60 km NNW of Kamloops, BC at 51°12'49" N 120°23'43" W, 1290 m above mean sea level. Scaling up from measurements for nine trees, throughfall, stemflow and canopy interception loss accounted for 87.7, 1.8 and 10.5 percent of the 252.9 mm of rain that fell over 38 events during the study period, respectively. The reformulated versions of the Gash and Liu analytical interception loss models estimated cumulative canopy interception loss at 24.7 and 24.6 mm, respectively, compared with the observed 26.5 mm; an underestimate of 1.8 and 1.9 mm or 6.8 and 7.2% of the observed value, respectively. Our results suggest that canopy interception loss is reduced in juvenile stands compared to their mature counterparts and that this reduction is due to the decreased storage capacity offered by these younger canopies. Evaporation during rainfall from juvenile canopies is still appreciable and may be a consequence of the increased proportion of the canopy exposed to wind during events.

  11. Partitioning of water flux in a Sierra Nevada ponderosa pine plantation

    Science.gov (United States)

    Kurpius, M.R.; Panek, J.A.; Nikolov, N.T.; McKay, M.; Goldstein, Allen H.

    2003-01-01

    The weather patterns of the west side of the Sierra Nevada Mountains (cold, wet winters and hot, dry summers) strongly influence how water is partitioned between transpiration and evaporation and result in a specific strategy of water use by ponderosa pine trees (Pinus ponderosa) in this region. To investigate how year-round water fluxes were partitioned in a young ponderosa pine ecosystem in the Sierra Nevada Mountains, water fluxes were continually measured from June 2000 to May 2001 using a combination of sap flow and eddy covariance techniques (above- and below-canopy). Water fluxes were modeled at our study site using a biophysical model, FORFLUX. During summer and fall water fluxes were equally partitioned between transpiration and soil evaporation while transpiration dominated the water fluxes in winter and spring. The trees had high rates of canopy conductance and transpiration in the early morning and mid-late afternoon and a mid-day depression during the dry season. We used a diurnal centroid analysis to show that the timing of high canopy conductance and transpiration relative to high vapor pressure deficit (D) shifted with soil moisture: during periods of low soil moisture canopy conductance and transpiration peaked early in the day when D was low. Conversely, during periods of high soil moisture canopy conductance and transpiration peaked at the same time or later in the day than D. Our observations suggest a general strategy by the pine trees in which they maximize stomatal conductance, and therefore carbon fixation, throughout the day on warm sunny days with high soil moisture (i.e. warm periods in winter and late spring) and maximize stomatal conductance and carbon fixation in the morning through the dry periods. FORFLUX model estimates of evaporation and transpiration were close to measured/calculated values during the dry period, including the drought, but underestimated transpiration and overestimated evaporation during the wet period. ?? 2003

  12. A comparison of the metabolism of the abortifacient compounds from Ponderosa pine needles in conditioned versus naive cattle.

    Science.gov (United States)

    Welch, K D; Gardner, D R; Pfister, J A; Panter, K E; Zieglar, J; Hall, J O

    2012-12-01

    Isocupressic acid (ICA) is the abortifacient compound in ponderosa pine (Pinus ponderosa L.) needles, which can cause late-term abortions in cattle (Bos taurus). However, cattle rapidly metabolize ICA to agathic acid (AGA) and subsequent metabolites. When pine needles are dosed orally to cattle, no ICA is detected in their serum, whereas AGA is readily detected. Recent research has demonstrated that AGA is also an abortifacient compound in cattle. The observation has been made that when cattle are dosed with labdane acids for an extended time, the concentration of AGA in serum increases for 1 to 2 d but then decreases to baseline after 5 to 6 d even though they are still being dosed twice daily. Therefore, in this study we investigated whether cattle conditioned to pine needles metabolize ICA, and its metabolites, faster than naïve cattle. Agathic acid was readily detected in the serum of naïve cattle fed ponderosa pine needles, whereas very little AGA was detected in the serum of cattle conditioned to pine needles. We also compared the metabolism of ICA in vitro using rumen cultures from pine-needle-conditioned and naïve cattle. In the rumen cultures from conditioned cattle, AGA concentrations were dramatically less than rumen cultures from naïve cattle. Thus, an adaptation occurs to cattle conditioned to pine needles such that the metabolism AGA by the rumen microflora is altered.

  13. Uptake and distribution of nitrogen from acidic fog within a ponderosa pine (Pinus ponderosa Laws.)/litter/soil system

    Energy Technology Data Exchange (ETDEWEB)

    Fenn, M.E.; Leininger, T.D.

    1995-11-01

    The magnitude and importance of wet deposition of N in forests of the South Coast (Los Angeles) Air Basin have not been well characterized. We exposed 3-yr-old ponderosa pine (Pinus ponderosa Laws.) seedlings growing in native forest soil to acidic fog treatments (pH 3.1) simulating fog chemistry from a pine forest near Los Angeles, California. Fog solutions contained either {sup 15}NH{sub 4}{sup +}, {sup 15}NO{sub 3}{sup {minus}}, or unlabeled N. The fog treatments were applied in open-top chambers in six 5-hr exposures. Soil treatments within each of the fog exposures were bare soil, soil overlain with L- and F-litter, and soil covered with plastic during the fog events to prevent fogwater from contacting soil. Seedlings were harvested and samples were collected 15 wk after the fog treatments. Uptake of {sup 15}N by roots was by far the dominant pathway for plant assimilation of fog-deposited {sup 15}N. Deposition of N in fog supplied 9.4% and 8.7% of the total N in current-year crown biomass in the litter-overlay and bare-soil treatments, respectively. Total N concentrations in every plant fraction except current-year stems were significantly higher in the bare-soil treatment than in the plastic-covered soil treatment. Less than 5% of the {sup 15}N deposited directly to the seedling crowns was retained by the plants in the covered-soil treatment, whereas 57% of the {sup 15}N deposited to the seedling/litter/soil systems was incorporated into plant biomass. The litter layers retained {sup 15}NH{sub 4}{sup +} more effectively than {sup 15}NH{sub 4}{sup +} more effectively than {sup 15}NO{sub 3}. Data from this study suggest that N deposited from fog may be an important source of N for plant growth in forests of the SCAB where fog occurrence and pollution exposure coincide. 5 refs., 5 figs., 3 tabs.

  14. The effect of water limitation on volatile emission, tree defense response, and brood success of Dendroctonus ponderosae in two pine hosts, lodgepole and jack pine

    Directory of Open Access Journals (Sweden)

    Inka eLusebrink

    2016-02-01

    Full Text Available The mountain pine beetle (MPB; Dendroctonus ponderosae has recently expanded its range from lodgepole pine forest into the lodgepole × jack pine hybrid zone in central Alberta, within which it has attacked pure jack pine. This study tested the effects of water limitation on tree defense response of mature lodgepole and jack pine (Pinus contorta and Pinus banksiana trees in the field. Tree defense response was initiated by inoculation of trees with the MPB-associated fungus Grosmannia clavigera and measured through monoterpene emission from tree boles and concentration of defensive compounds in phloem, needles, and necrotic tissues. Lodgepole pine generally emitted higher amounts of monoterpenes than jack pine; particularly from fungal-inoculated trees. Compared to non-inoculated trees, fungal inoculation increased monoterpene emission in both species, whereas water treatment had no effect on monoterpene emission. The phloem of both pine species contains (--α-pinene, the precursor of the beetle’s aggregation pheromone, however lodgepole pine contains two times as much as jack pine. The concentration of defensive compounds was 70-fold greater in the lesion tissue in jack pine, but only 10-fold in lodgepole pine compared to healthy phloem tissue in each species, respectively. Water-deficit treatment inhibited an increase of L-limonene as response to fungal inoculation in lodgepole pine phloem. The amount of myrcene in jack pine phloem was higher in water-deficit trees compared to ambient trees. Beetles reared in jack pine were not affected by either water or biological treatment, whereas beetles reared in lodgepole pine benefited from fungal inoculation by producing larger and heavier female offspring. Female beetles that emerged from jack pine bolts contained more fat than those that emerged from lodgepole pine, even though lodgepole pine phloem had a higher nitrogen content than jack pine phloem. These results suggest that jack pine chemistry

  15. Forest stand dynamics of shortleaf pine in the Ozarks

    Science.gov (United States)

    David R. Larsen

    2007-01-01

    Much has been written on the management of shortleaf pine in the Ozarks (Brinkman et al. 1965, Brinkman 1967, Brinkman and Smith 1968, Seidel and Rogers 1965, Seidel and Rogers 1966). In large portions of the Ozarks, shortleaf pine does not grow in pure stands but rather in mixes with various oak species. These mixes present unique challenges in finding the set of...

  16. Douglas-Fir Tussock Moth- and Douglas-Fir Beetle-Caused Mortality in a Ponderosa Pine/Douglas-Fir Forest in the Colorado Front Range, USA

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    José F. Negrón

    2014-12-01

    Full Text Available An outbreak of the Douglas-fir tussock moth, Orgyia pseudotsugata McDunnough, occurred in the South Platte River drainage on the Pike-San Isabel National Forest in the Colorado Front Range attacking Douglas-fir, Pseudotsuga menziesii (Mirb. Franco. Stocking levels, species composition, and tree size in heavily and lightly defoliated stands were similar. Douglas-fir tussock moth defoliation resulted in significant Douglas-fir mortality in the heavily defoliated stands, leading to a change in dominance to ponderosa pine, Pinus ponderosa Lawson. Douglas-fir beetle, Dendroctonus pseudotsuqae Hopkins, populations increased following the defoliation event but caused less mortality, and did not differ between heavily and lightly defoliated stands. Douglas-fir tussock moth-related mortality was greatest in trees less than 15 cm dbh (diameter at 1.4 m above the ground that grew in suppressed and intermediate canopy positions. Douglas-fir beetle-related mortality was greatest in trees larger than 15 cm dbh that grew in the dominant and co-dominant crown positions. Although both insects utilize Douglas-fir as its primary host, stand response to infestation is different. The extensive outbreak of the Douglas-fir tussock moth followed by Douglas-fir beetle activity may be associated with a legacy of increased host type growing in overstocked conditions as a result of fire exclusion.

  17. Impacts of silvicultural thinning treatments on beetle trap captures and tree attacks during low bark beetle populations in ponderosa pine forests of northern Arizona.

    Science.gov (United States)

    Gaylord, M L; Hofstetter, R W; Wagner, M R

    2010-10-01

    Our research used a combination of passive traps, funnel traps with lures, baited trees, and surveys of long-term thinning plots to assess the impacts of different levels of stand basal area (BA) on bark beetle tree attack and on trap captures of Ips spp., Dendroctonus spp., and their predators. The study occurred at two sites in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests, from 2004 to 2007 during low bark beetle populations. Residual stand BA ranged from 9.0 to 37.0 m2/ha. More predators and bark beetles were collected in passive traps in stands of lower BA than in stands of higher BA; however, significance varied by species and site, and total number of beetles collected was low. Height of the clear panel passive traps affected trap catches for some species at some sites and years. When pheromone lures were used with funnel traps [Ips pini (Say) lure: lanierone, +03/-97 ipsdienol], we found no significant difference in trap catches among basal area treatments for bark beetles and their predators. Similarly, when trees were baited (Dendroctonus brevicomis LeConte lure: myrcene, exo-brevicomin and frontalin), we found no significant difference for days to first bark beetle attack. Surveys of long-term thinning treatments found evidence of bark beetle attacks only in unthinned plots (approximately 37 m2/ha basal area). We discuss our results in terms of management implications for bark beetle trapping and control.

  18. Chloroplastic responses of ponderosa pine (Pinus ponderosa) seedlings to ozone exposure.

    Science.gov (United States)

    Anderson, Paul D; Palmer, Brent; Houpis, James L J; Smith, Mary K; Pushnik, James C

    2003-06-01

    Integrity of chloroplast membranes is essential to photosynthesis. Loss of thylakoid membrane integrity has been proposed as a consequence of ozone (O(3)) exposure and therefore may be a mechanistic basis for decreased photosynthetic rates commonly associated with ozone exposure. To investigate this hypothesis, Pinus ponderosa seedlings were exposed to ambient air or ozone concentrations maintained at 0.15 or 0.30 microliter l(-1) for 10 h day(-1) for 51 days during their second growing season. Over the course of the study, foliage samples were periodically collected for thylakoid membrane, chlorophyll and protein analyses. Additionally, gas-exchange measurements were made in conjunction with foliage sampling to verify that observed chloroplastic responses were associated with ozone-induced changes in photosynthesis. Needles exposed to elevated ozone exhibited decreases in chlorophyll a and b content. The decreases were dependent on the duration and intensity of ozone exposure. When based on equal amounts of chlorophyll, ozone-exposed sample tissue exhibited an increase in total protein. When based on equal amounts of protein, ozone-exposed samples exhibited an increase in 37 kDa proteins, possibly consisting of breakdown products, and a possible decrease in 68 kDa proteins, Rubisco small subunit. There was also a change in the ratio of Photosystem I protein complexes CPI and CPII that may have contributed to decreased photosynthesis. Net photosynthetic rates were decreased in the high ozone treatment suggesting that observed structural and biochemical changes in the chloroplast were associated with alterations of the photosynthetic process.

  19. Isolation and characterization of 16 microsatellite loci in the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    C. S. Davis; K. E. Mock; B. J. Bentz; S. M. Bromilow; N. V. Bartell; B. W. Murray; A. D. Roe; J. E. K. Cooke

    2009-01-01

    We isolated 16 polymorphic microsatellite loci in the mountain pine beetle (Dendroctonus ponderosae Hopkins) and developed conditions for amplifying these markers in four multiplex reactions. Three to 14 alleles were detected per locus across two sampled populations. Observed and expected heterozygosities ranged from 0.000 to 0.902 and from 0.100 to 0.830, respectively...

  20. Spatial variability of surface fuels in treated and untreated ponderosa pine forests of the southern Rocky Mountains

    Science.gov (United States)

    Emma Vakili; Chad M. Hoffman; Robert E. Keane; Wade T. Tinkham; Yvette Dickinson

    2016-01-01

    There is growing consensus that spatial variability in fuel loading at scales down to 0.5 m may govern fire behaviour and effects. However, there remains a lack of understanding of how fuels vary through space in wildland settings. This study quantifies surface fuel loading and its spatial variability in ponderosa pine sites before and after fuels treatment in the...

  1. Two-dimensional heat flow analysis applied to heat sterilization of ponderosa pine and Douglas-fir square timbers

    Science.gov (United States)

    William T. Simpson

    2004-01-01

    Equations for a two-dimensional finite difference heat flow analysis were developed and applied to ponderosa pine and Douglas-fir square timbers to calculate the time required to heat the center of the squares to target temperature. The squares were solid piled, which made their surfaces inaccessible to the heating air, and thus surface temperatures failed to attain...

  2. Effect of body condition on consumption of pine needles (Pinus ponderosa) by beef cows.

    Science.gov (United States)

    Pfister, J A; Panter, K E; Gardner, D R; Cook, D; Welch, K D

    2008-12-01

    We determined whether cows in low (LBC) or high body condition (HBC) would consume different amounts of green pine needles (Pinus ponderosa). Cows (mature; open Hereford and Hereford x Angus) were fed a maintenance basal diet (alfalfa pellets) for Exp. 1 and 2; during Exp. 3 and 4, cows were fed high-protein and high-energy diets, respectively. Experiment 5 was a grazing study on rangeland during winter in South Dakota; diets were determined by using bite counts. Mean BCS (1 = emaciated, 9 = obese) was 7.5 for HBC cows and <4.0 for LBC cows during the experiments. During Exp. 1, LBC cows consumed more (P = 0.001) pine needles than did HBC cows (5.5 +/- 0.25 vs. 1.0 +/- 0.14 g/kg of BW daily, respectively). During Exp. 2, there was a day x treatment interaction (P = 0.001) as LBC cows consumed variable, but greater, amounts of pine needles than did HBC cows (3.7 +/- 0.19 vs. 1.3 +/- 0.12 g/kg of BW daily, respectively). When fed a high-protein/low-energy diet, LBC cows ate more (P = 0.04) pine needles than did HBC cows. When fed a low-protein/high-energy diet, there was a day x treatment interaction (P = 0.001) because LBC cows consumed more pine needles than did HBC cows for the first 3 d of the study, and then consumption by LBC animals decreased during the last 4 d. These experiments suggest that the protein:energy ratio may be an important factor in the ability of cows to tolerate terpenes, and that cows were not able to sustain an increased quantity of needle consumption on a low-protein diet. During the 25-d grazing study, there was a day x treatment interaction (P = 0.001) as LBC animals selected more pine needles (up to 25% of daily bites) on some days compared with HBC cows. Weather influenced pine needle consumption because pine needle bites by LBC cows were related (r(2) = 0.60; P = 0.001) to days of greater snow depth and lower minimum daily temperatures. Both LBC and HBC cows increased selection of pine needles from trees during cold, snowy weather, but

  3. Spatiotemporal Dynamics of Fire in Whitebark Pine Stands on two Mountains in the Lolo National Forest, Montana, USA.

    Science.gov (United States)

    Larson, E. R.; Grissino-Mayer, H. D.

    2004-12-01

    Whitebark pine (Pinus albicaulis) is a long-lived tree species that exists throughout high elevation and treeline forest communities of western North America. It is the foundation of a diminishing ecosystem that supports Clark's nutcrackers (Nucifraga columbiana), red squirrels (Tamiasciurus hudsonicus), grizzly bears (Ursus arctos), and black bears (U. americana). Several factors are directly linked to the decline of the whitebark pine ecosystem: mortality from recent and widespread mountain pine beetle (Dendroctonus ponderosae) outbreaks, infestation by the invasive white pine blister rust (Cronartium ribicola, an exotic fungal canker that weakens and eventually kills white pines), and fire suppression that may have altered the historic fire regime and enabled fire-intolerant tree species to encroach upon whitebark pine stands. The synergistic effects of these factors have led to a dramatic decline in whitebark pine communities throughout its native range, and in response land managers and conservationists have called for research to better understand the ecological dynamics of this little studied ecosystem. My research uses dendrochronology to investigate the fire history of whitebark pine stands on three mountains in the Lolo National Forest, Montana, via fire-scar and age structure analyses. I present here the results from the fire-scar analyses from Morrell Mountain where I obtained 40 cross sections from dead and down whitebark pines. Individual tree mean fire return intervals (MFRI) range from 33 to 119 years, with a stand MFRI of 49 years that includes fire scars dating to the 16th century. Fire events scarred multiple trees in AD 1754, 1796, and 1843, indicating a mixed-severity fire regime. The majority of the samples recorded a frost event in AD 1601, perhaps evidence of the AD 1600 eruption of Mt. Huaynapatina in the Peruvian Andes. My research not only provides an historical framework for land managers, but also provides an opportunity to examine long

  4. Climate change will restrict ponderosa pine forest regeneration in the 21st century in absence of disturbance

    Science.gov (United States)

    Petrie, M. D.; Bradford, J. B.; Hubbard, R. M.; Lauenroth, W. K.; Andrews, C.

    2016-12-01

    The persistence of ponderosa pine forests and the ability for these forests to colonize new habitats in the 21st century will be influenced by how climate change supports ponderosa pine regeneration through the demographic processes of seed production, germination and survival. Yet, the way that climate change may support or restrict the frequency of successful regeneration is unclear. We developed a quantitative, criteria-based framework to estimate ponderosa pine regeneration potential (RP: a metric from 0-1) in response to climate forcings and environmental conditions. We used the SOILWAT ecosystem water balance model to simulate drivers of air and soil temperature, evaporation and soil moisture availability for 47 ponderosa pine sites across the western United States, using meteorological data from 1910-2014, and projections from nine General Circulation Models and the RCP 8.5 emissions scenario for 2020-2099. Climate change simulations increased the success of early developmental stages of seed production and germination, and supported 49.7% higher RP in 2020-2059 compared to averages from 1910-2014. As temperatures increased in 2060-2099, survival scores decreased, and RP was reduced by 50.3% compared to 1910-2014. Although the frequency of years with high RP did not change in 2060-2099 (12% of years), the frequency of years with very low RP increased from 25% to 58% of years. Thus, climate change will initially support higher RP and more favorable years in 2020-2059, yet will reduce average RP and the frequency of years with moderate regeneration support in 2060-2099. Forest regeneration is complex and not fully-understood, but our results suggest it is likely that climate change alone will instigate restrictions to the persistence and expansion of ponderosa pine in the 21st century.

  5. Making a stand: five centuries of population growth in colonizing populations of Pinus ponderosa.

    Science.gov (United States)

    Lesser, Mark R; Jackson, Stephen T

    2012-05-01

    The processes underlying the development of new populations are important for understanding how species colonize new territory and form viable long-term populations. Life-history-mediated processes such as Allee effects and dispersal capability may interact with climate variability and site-specific factors to govern population success and failure over extended time frames. We studied four disjunct populations of ponderosa pine in the Bighorn Basin of north-central Wyoming to examine population growth spanning more than five centuries. The study populations are separated from continuous ponderosa pine forest by distances ranging from 15 to >100 km. Strong evidence indicates that the initial colonizing individuals are still present, yielding a nearly complete record of population history. All trees in each population were aged using dendroecological techniques. The populations were all founded between 1530 and 1655 cal yr CE. All show logistic growth patterns, with initial exponential growth followed by a slowing during the mid to late 20th century. Initial population growth was slower than expectations from a logistic regression model at all four populations, but increased during the mid-18th century. Initial lags in population growth may have been due to strong Allee effects. A combination of overcoming Allee effects and a transition to favorable climate conditions may have facilitated a mid-18th century pulse in population growth rate.

  6. Mountain pine beetle in lodgepole pine: mortality and fire implications (Project INT-F-07-03)

    Science.gov (United States)

    Jennifer G. Klutsch; Daniel R. West; Mike A Battaglia; Sheryl L. Costello; José F. Negrón; Charles C. Rhoades; John Popp; Rick Caissie

    2013-01-01

    Mountain pine beetle (Dendroctonus ponderosae Hopkins) has infested over 2 million acres of lodgepole pine (Pinus contorta Dougl. ex Loud.) forest since an outbreak began approximately in 2000 in north central Colorado. The tree mortality from mountain pine beetle outbreaks has the potential to alter stand composition and stand...

  7. Silvicultural Considerations in Managing Southern Pine Stands in the Context of Southern Pine Beetle

    Science.gov (United States)

    James M. Guldin

    2011-01-01

    Roughly 30 percent of the 200 million acres of forest land in the South supports stands dominated by southern pines. These are among the most productive forests in the nation. Adapted to disturbance, southern pines are relatively easy to manage with even-aged methods such as clearcutting and planting, or the seed tree and shelterwood methods with natural regeneration....

  8. A review of precipitation and temperature control on seedling emergence and establishment for ponderosa and lodgepole pine forest regeneration

    Science.gov (United States)

    Petrie, Matthew; Wildeman, A.M.; Bradford, John B.; Hubbard, R.M.; Lauenroth, W.K.

    2016-01-01

    The persistence of ponderosa pine and lodgepole pine forests in the 21st century depends to a large extent on how seedling emergence and establishment are influenced by driving climate and environmental variables, which largely govern forest regeneration. We surveyed the literature, and identified 96 publications that reported data on dependent variables of seedling emergence and/or establishment and one or more independent variables of air temperature, soil temperature, precipitation and moisture availability. Our review suggests that seedling emergence and establishment for both species is highest at intermediate temperatures (20 to 25 °C), and higher precipitation and higher moisture availability support a higher percentage of seedling emergence and establishment at daily, monthly and annual timescales. We found that ponderosa pine seedlings may be more sensitive to temperature fluctuations whereas lodgepole pine seedlings may be more sensitive to moisture fluctuations. In a changing climate, increasing temperatures and declining moisture availability may hinder forest persistence by limiting seedling processes. Yet, only 23 studies in our review investigated the effects of driving climate and environmental variables directly. Furthermore, 74 studies occurred in a laboratory or greenhouse, which do not often replicate the conditions experienced by tree seedlings in a field setting. It is therefore difficult to provide strong conclusions on how sensitive emergence and establishment in ponderosa and lodgepole pine are to these specific driving variables, or to investigate their potential aggregate effects. Thus, the effects of many driving variables on seedling processes remain largely inconclusive. Our review stresses the need for additional field and laboratory studies to better elucidate the effects of driving climate and environmental variables on seedling emergence and establishment for ponderosa and lodgepole pine.

  9. Defoliation of interior Douglas-fir elicits carbon transfer and stress signalling to ponderosa pine neighbors through ectomycorrhizal networks.

    Science.gov (United States)

    Song, Yuan Yuan; Simard, Suzanne W; Carroll, Allan; Mohn, William W; Zeng, Ren Sen

    2015-02-16

    Extensive regions of interior Douglas-fir (Pseudotsuga menziesii var. glauca, IDF) forests in North America are being damaged by drought and western spruce budworm (Choristoneura occidentalis). This damage is resulting from warmer and drier summers associated with climate change. To test whether defoliated IDF can directly transfer resources to ponderosa pine (Pinus ponderosae) regenerating nearby, thus aiding in forest recovery, we examined photosynthetic carbon transfer and defense enzyme response. We grew pairs of ectomycorrhizal IDF 'donor' and ponderosa pine 'receiver' seedlings in pots and isolated transfer pathways by comparing 35 μm, 0.5 μm and no mesh treatments; we then stressed IDF donors either through manual defoliation or infestation by the budworm. We found that manual defoliation of IDF donors led to transfer of photosynthetic carbon to neighboring receivers through mycorrhizal networks, but not through soil or root pathways. Both manual and insect defoliation of donors led to increased activity of peroxidase, polyphenol oxidase and superoxide dismutase in the ponderosa pine receivers, via a mechanism primarily dependent on the mycorrhizal network. These findings indicate that IDF can transfer resources and stress signals to interspecific neighbors, suggesting ectomycorrhizal networks can serve as agents of interspecific communication facilitating recovery and succession of forests after disturbance.

  10. Maize, switchgrass, and ponderosa pine biochar added to soil increased herbicide sorption and decreased herbicide efficacy.

    Science.gov (United States)

    Clay, Sharon A; Krack, Kaitlynn K; Bruggeman, Stephanie A; Papiernik, Sharon; Schumacher, Thomas E

    2016-08-02

    Biochar, a by-product of pyrolysis made from a wide array of plant biomass when producing biofuels, is a proposed soil amendment to improve soil health. This study measured herbicide sorption and efficacy when soils were treated with low (1% w/w) or high (10% w/w) amounts of biochar manufactured from different feedstocks [maize (Zea mays) stover, switchgrass (Panicum vigatum), and ponderosa pine (Pinus ponderosa)], and treated with different post-processing techniques. Twenty-four hour batch equilibration measured sorption of (14)C-labelled atrazine or 2,4-D to two soil types with and without biochar amendments. Herbicide efficacy was measured with and without biochar using speed of seed germination tests of sensitive species. Biochar amended soils sorbed more herbicide than untreated soils, with major differences due to biochar application rate but minor differences due to biochar type or post-process handling technique. Biochar presence increased the speed of seed germination compared with herbicide alone addition. These data indicate that biochar addition to soil can increase herbicide sorption and reduce efficacy. Evaluation for site-specific biochar applications may be warranted to obtain maximal benefits without compromising other agronomic practices.

  11. Elevated CO2 and O3 effects on fine-root survivorship in ponderosa pine mesocosms.

    Science.gov (United States)

    Phillips, Donald L; Johnson, Mark G; Tingey, David T; Storm, Marjorie J

    2009-07-01

    Atmospheric carbon dioxide (CO(2)) and ozone (O(3)) concentrations are rising, which may have opposing effects on tree C balance and allocation to fine roots. More information is needed on interactive CO(2) and O(3) effects on roots, particularly fine-root life span, a critical demographic parameter and determinant of soil C and N pools and cycling rates. We conducted a study in which ponderosa pine (Pinus ponderosa) seedlings were exposed to two levels of CO(2) and O(3) in sun-lit controlled-environment mesocosms for 3 years. Minirhizotrons were used to monitor individual fine roots in three soil horizons every 28 days. Proportional hazards regression was used to analyze effects of CO(2), O(3), diameter, depth, and season of root initiation on fine-root survivorship. More fine roots were produced in the elevated CO(2) treatment than in ambient CO(2). Elevated CO(2), increasing root diameter, and increasing root depth all significantly increased fine-root survivorship and median life span. Life span was slightly, but not significantly, lower in elevated O(3), and increased O(3) did not reduce the effect of elevated CO(2). Median life spans varied from 140 to 448 days depending on the season of root initiation. These results indicate the potential for elevated CO(2) to increase the number of fine roots and their residence time in the soil, which is also affected by root diameter, root depth, and phenology.

  12. Height-related growth declines in ponderosa pine are not due to carbon limitation.

    Science.gov (United States)

    Sala, Anna; Hoch, Günter

    2009-01-01

    Decreased gas exchange as trees grow tall has been proposed to explain age-related growth declines in trees. We examined changes of mobile carbon stores (starch, sugars and lipids) with tree height in ponderosa pine (Pinus ponderosa) at two sites differing in water availability, and tested the following hypotheses: (1) carbon supply does not become increasingly limited as trees grow tall; rather, the concentration of mobile carbon compounds increases with tree height reflecting greater reductions of carbon sink activities relative to carbon assimilation; and (2) increases of stored mobile carbon compounds with tree height are greater in drier sites. Height-related growth reductions were associated with significant increases of non-structural carbohydrates (NSC) and lipid concentrations in all tissues in the upper canopy and of NSC in the bole. Lipid concentrations in the bole decreased with tree height, but such decrease is not necessarily inconsistent with non-limiting carbon supply in tall trees. Furthermore, we found stronger increases of mobile carbon stores with tree height at the dry site relative to the moist site. Our results provide first direct evidence that carbon supply does not limit growth in tall trees and that decreases of water availability might negatively impact growth processes more than net-photosynthesis.

  13. Resiliency of an Interior Ponderosa Pine Forest to Bark Beetle Infestations Following Fuel-Reduction and Forest-Restoration Treatments

    Directory of Open Access Journals (Sweden)

    Christopher J. Fettig

    2014-01-01

    Full Text Available Mechanical thinning and the application of prescribed fire are commonly used to restore fire-adapted forest ecosystems in the Western United States. During a 10-year period, we monitored the effects of fuel-reduction and forest-restoration treatments on levels of tree mortality in an interior ponderosa pine, Pinus ponderosa Dougl. ex Laws., forest in California. Twelve experimental plots, ranging in size from 77–144 ha, were established to create two distinct forest structural types: mid-seral stage (low structural diversity; LoD and late-seral stage (high structural diversity; HiD. Following harvesting, half of each plot was treated with prescribed fire (B. A total of 16,473 trees (8.7% of all trees died during the 10-year period. Mortality was primarily attributed to bark beetles (Coleoptera: Curculionidae, Scolytinae (10,655 trees, specifically fir engraver, Scolytus ventralis LeConte, mountain pine beetle, Dendroctonus ponderosae Hopkins, western pine beetle, D. brevicomis LeConte, pine engraver, Ips pini (Say, and, to a much lesser extent, Jeffrey pine beetle, D. jeffreyi Hopkins. Trees of all ages and size classes were killed, but mortality was concentrated in the smaller-diameter classes (19–29.2 and 29.3–39.3 cm at 1.37 m in height. Most mortality occurred three to five years following prescribed burns. Higher levels of bark beetle-caused tree mortality were observed on LoD + B (8.7% than LoD (4.2%. The application of these and other results to the   management of interior P. ponderosa forests are discussed, with an emphasis on the maintenance of large trees.

  14. Carbon and water fluxes from ponderosa pine forests disturbed by wildfire and thinning.

    Science.gov (United States)

    Dore, S; Kolb, T E; Montes-Helu, M; Eckert, S E; Sullivan, B W; Hungate, B A; Kaye, J P; Hart, S C; Koch, G W; Finkral, A

    2010-04-01

    Disturbances alter ecosystem carbon dynamics, often by reducing carbon uptake and stocks. We compared the impact of two types of disturbances that represent the most likely future conditions of currently dense ponderosa pine forests of the southwestern United States: (1) high-intensity fire and (2) thinning, designed to reduce fire intensity. High-severity fire had a larger impact on ecosystem carbon uptake and storage than thinning. Total ecosystem carbon was 42% lower at the intensely burned site, 10 years after burning, than at the undisturbed site. Eddy covariance measurements over two years showed that the burned site was a net annual source of carbon to the atmosphere whereas the undisturbed site was a sink. Net primary production (NPP), evapotranspiration (ET), and water use efficiency were lower at the burned site than at the undisturbed site. In contrast, thinning decreased total ecosystem carbon by 18%, and changed the site from a carbon sink to a source in the first posttreatment year. Thinning also decreased ET, reduced the limitation of drought on carbon uptake during summer, and did not change water use efficiency. Both disturbances reduced ecosystem carbon uptake by decreasing gross primary production (55% by burning, 30% by thinning) more than total ecosystem respiration (TER; 33-47% by burning, 18% by thinning), and increased the contribution of soil carbon dioxide efflux to TER. The relationship between TER and temperature was not affected by either disturbance. Efforts to accurately estimate regional carbon budgets should consider impacts on carbon dynamics of both large disturbances, such as high-intensity fire, and the partial disturbance of thinning that is often used to prevent intense burning. Our results show that thinned forests of ponderosa pine in the southwestern United States are a desirable alternative to intensively burned forests to maintain carbon stocks and primary production.

  15. Restoring forest structure and process stabilizes forest carbon in wildfire-prone southwestern ponderosa pine forests.

    Science.gov (United States)

    Hurteau, Matthew D; Liang, Shuang; Martin, Katherine L; North, Malcolm P; Koch, George W; Hungate, Bruce A

    2016-03-01

    Changing climate and a legacy of fire-exclusion have increased the probability of high-severity wildfire, leading to an increased risk of forest carbon loss in ponderosa pine forests in the southwestern USA. Efforts to reduce high-severity fire risk through forest thinning and prescribed burning require both the removal and emission of carbon from these forests, and any potential carbon benefits from treatment may depend on the occurrence of wildfire. We sought to determine how forest treatments alter the effects of stochastic wildfire events on the forest carbon balance. We modeled three treatments (control, thin-only, and thin and burn) with and without the occurrence of wildfire. We evaluated how two different probabilities of wildfire occurrence, 1% and 2% per year, might alter the carbon balance of treatments. In the absence of wildfire, we found that thinning and burning treatments initially reduced total ecosystem carbon (TEC) and increased net ecosystem carbon balance (NECB). In the presence of wildfire, the thin and burn treatment TEC surpassed that of the control in year 40 at 2%/yr wildfire probability, and in year 51 at 1%/yr wildfire probability. NECB in the presence of wildfire showed a similar response to the no-wildfire scenarios: both thin-only and thin and burn treatments increased the C sink. Treatments increased TEC by reducing both mean wildfire severity and its variability. While the carbon balance of treatments may differ in more productive forest types, the carbon balance benefits from restoring forest structure and fire in southwestern ponderosa pine forests are clear.

  16. Quantifying post-fire ponderosa pine snags using GIS techniques on scanned aerial photographs

    Science.gov (United States)

    Kent, Kevin

    Snags are an important component of forest ecosystems because of their utility in forest-nutrient cycling and provision of critical wildlife habitat, as well as associated fuel management concerns relating to coarse woody debris (CWD). Knowledge of snag and CWD trajectories are needed for land managers to plan for long-term ecosystem change in post-fire regimes. This need will likely be exacerbated by increasingly warm and dry climatic conditions projected for the U.S. Southwest. One of the best prospects for studying fire-induced landscape change beyond the plot scale, but still at a resolution sufficient to resolve individual snags, is to utilize the available aerial photography record. Previous field-based studies of snag and CWD loads in the Southwest have relied on regional chronosequences to judge the recovery dynamic of ponderosa pine (Pinus ponderosa) burns. This previous research has been spatially and temporally restricted because of field survey extent limitations and uncertainty associated with the chronosequence approach (i.e., space-for-time substitution), which does not consider differences between specific site conditions and histories. This study develops highly automated methods for remotely quantifying and characterizing the spatial and temporal distribution of large snags associated with severe forest fires from very high resolution (VHR) landscape imagery I obtained from scans of aerial photos. Associated algorithms utilize the sharp edges, shape, shadow, and contrast characteristics of snags to enable feature recognition. Additionally, using snag shadow length, image acquisition time, and location information, heights were estimated for each identified snag. Furthermore, a novel solution was developed for extracting individual snags from areas of high snag density by overlaying parallel lines in the direction of the snag shadows and extracting local maxima lines contained by each snag polygon. Field survey data coincident to imagery coverage

  17. Mountain pine beetle infestations in relation to lodgepole pine diameters

    Science.gov (United States)

    Walter E. Cole; Gene D. Amman

    1969-01-01

    Tree losses resulting from infestation by the mountain pine beetle (Dendroctonus ponderosae Hopkins) were measured in two stands of lodgepole pine (Pinus contorta Dougl.) where the beetle population had previously been epidemic. Measurement data showed that larger diameter trees were infested and killed first. Tree losses...

  18. 87Sr/86Sr sourcing of ponderosa pine used in Anasazi great house construction at Chaco Canyon, New Mexico

    Science.gov (United States)

    Reynolds, Amanda C.; Betancourt, Julio L.; Quade, Jay; Patchett, P. Jonathan; Dean, Jeffery S.; Stein, John

    2005-01-01

    Previous analysis of 87Sr/86Sr ratios shows that 10th through 12th century Chaco Canyon was provisioned with plant materials that came from more than 75 km away. This includes (1) corn (Zea mays) grown on the eastern flanks of the Chuska Mountains and floodplain of the San Juan River to the west and north, and (2) spruce (Picea sp.) and fir (Abies sp.) beams from the crest of the Chuska and San Mateo Mountains to the west and south. Here, we extend 87Sr/86Sr analysis to ponderosa pine (Pinus ponderosa) prevalent in the architectural timber at three of the Chacoan great houses (Pueblo Bonito, Chetro Ketl, Pueblo del Arroyo). Like the architectural spruce and fir, much of the ponderosa matches the 87Sr/86Sr ratios of living trees in the Chuska Mountains. Many of the architectural ponderosa, however, have similar ratios to living trees in the La Plata and San Juan Mountains to the north and Lobo Mesa/Hosta Butte to the south. There are no systematic patterns in spruce/fir or ponderosa provenance by great house or time, suggesting the use of stockpiles from a few preferred sources. The multiple and distant sources for food and timber, now based on hundreds of isotopic values from modern and archeological samples, confirm conventional wisdom about the geographic scope of the larger Chacoan system. The complexity of this procurement warns against simple generalizations based on just one species, a single class of botanical artifact, or a few isotopic values.

  19. Destroyed virgin longleaf pine stand lives-on digitally

    Science.gov (United States)

    John C. Gilbert; S. Kush; Rebecca J. Barlow

    2015-01-01

    The Flomaton Natural Area (FNA) once stood as one of the few remnant fragments of virgin, old-growth longleaf pine stands (Pinus palustris Mill.) in the Southeast. This 80-acre stand contained trees over 200 years old. A restoration effort began in 1994 to remove off-site trees and to reintroduce fire to the site after over 40 years of fire suppression. A geographic...

  20. Using acoustic analysis to presort warp-prone ponderosa pine 2 by 4s before kiln-drying

    Science.gov (United States)

    Xiping Wang; William T. Simpson

    2006-01-01

    This study evaluated the potential of acoustic analysis as presorting criteria to identify warp-prone boards before kiln-drying. Dimension lumber, 38 by 89 mm (nominal 2 by 4 in.) and 2.44 m (8 it) long, sawn from open-grown small-diameter ponderosa pine trees, was acoustically tested lengthwise at green condition. Three acoustic properties (acoustic speed, rate of...

  1. Modeling of SAR returns from a red pine stand

    Science.gov (United States)

    Lang, R. H.; Kilic, O.; Chauhan, N. S.; Ranson, J.

    1992-01-01

    Bright P-band radar returns from red pine forests have been observed on synthetic aperture radar (SAR) images in Bangor, Maine. A plot of red pine trees was selected for the characterization and modeling to understand the cause of the high P-band returns. The red pine stand under study consisted of mature trees. Diameter at breast height (DBH) measurements were made to determine stand density as a function of tree diameter. Soil moisture and bulk density measurements were taken along with ground rough surface profiles. Detailed biomass measurements of the needles, shoots, branches, and trunks were also taken. These site statistics have been used in a distorted Born approximation model of the forest. Computations indicate that the direct-reflected or the double-bounce contributions from the ground are responsible for the high observed P-band returns for HH polarization.

  2. Seasonal shifts in accumulation of glycerol biosynthetic gene transcripts in mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, larvae

    Directory of Open Access Journals (Sweden)

    Jordie D. Fraser

    2017-06-01

    Full Text Available Winter mortality is a major factor regulating population size of the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae. Glycerol is the major cryoprotectant in this freeze intolerant insect. We report findings from a gene expression study on an overwintering mountain pine beetle population over the course of 35 weeks. mRNA transcript levels suggest glycerol production in the mountain pine beetle occurs through glycogenolytic, gluconeogenic and potentially glyceroneogenic pathways, but not from metabolism of lipids. A two-week lag period between fall glycogen phosphorylase transcript and phosphoenolpyruvate carboxykinase transcript up-regulation suggests that gluconeogenesis serves as a secondary glycerol-production process, subsequent to exhaustion of the primary glycogenolytic source. These results provide a first look at the details of seasonal gene expression related to the production of glycerol in the mountain pine beetle.

  3. Sensitivity of ring growth and carbon allocation to climatic variation vary within ponderosa pine trees.

    Science.gov (United States)

    Kerhoulas, Lucy P; Kane, Jeffrey M

    2012-01-01

    Most dendrochronological studies focus on cores sampled from standard positions (main stem, breast height), yet vertical gradients in hydraulic constraints and priorities for carbon allocation may contribute to different growth sensitivities with position. Using cores taken from five positions (coarse roots, breast height, base of live crown, mid-crown branch and treetop), we investigated how radial growth sensitivity to climate over the period of 1895-2008 varies by position within 36 large ponderosa pines (Pinus ponderosa Dougl.) in northern Arizona. The climate parameters investigated were Palmer Drought Severity Index, water year and monsoon precipitation, maximum annual temperature, minimum annual temperature and average annual temperature. For each study tree, we generated Pearson correlation coefficients between ring width indices from each position and six climate parameters. We also investigated whether the number of missing rings differed among positions and bole heights. We found that tree density did not significantly influence climatic sensitivity to any of the climate parameters investigated at any of the sample positions. Results from three types of analyses suggest that climatic sensitivity of tree growth varied with position height: (i) correlations of radial growth and climate variables consistently increased with height; (ii) model strength based on Akaike's information criterion increased with height, where treetop growth consistently had the highest sensitivity and coarse roots the lowest sensitivity to each climatic parameter; and (iii) the correlation between bole ring width indices decreased with distance between positions. We speculate that increased sensitivity to climate at higher positions is related to hydraulic limitation because higher positions experience greater xylem tensions due to gravitational effects that render these positions more sensitive to climatic stresses. The low sensitivity of root growth to all climatic variables

  4. Bole girdling affects metabolic properties and root, trunk and branch hydraulics of young ponderosa pine trees.

    Science.gov (United States)

    Domec, Jean-Christophe; Pruyn, Michele L

    2008-10-01

    Effects of trunk girdling on seasonal patterns of xylem water status, water transport and woody tissue metabolic properties were investigated in ponderosa pine (Pinus ponderosa Dougl. ex P. Laws.) trees. At the onset of summer, there was a sharp decrease in stomatal conductance (g(s)) in girdled trees followed by a full recovery after the first major rainfall in September. Eliminating the root as a carbohydrate sink by girdling induced a rapid reversible reduction in g(s). Respiratory potential (a laboratory measure of tissue-level respiration) increased above the girdle (branches and upper trunk) and decreased below the girdle (lower trunk and roots) relative to control trees during the growing season, but the effect was reversed after the first major rainfall. The increase in branch respiratory potential induced by girdling suggests that the decrease in g(s) was caused by the accumulation of carbohydrates above the girdle, which is consistent with an observed increase in leaf mass per area in the girdled trees. Trunk girdling did not affect native xylem embolism or xylem conductivity. Both treated and control trunks experienced loss of xylem conductivity ranging from 10% in spring to 30% in summer. Girdling reduced xylem growth and sapwood to leaf area ratio, which in turn reduced branch leaf specific conductivity (LSC). The girdling-induced reductions in g(s) and transpiration were associated with a decrease in leaf hydraulic conductance. Two years after girdling, when root-to-shoot phloem continuity had been restored, girdled trees had a reduced density of new wood, which increased xylem conductivity and whole-tree LSC, but also vulnerability to embolism.

  5. Community occupancy responses of small mammals to restoration treatments in ponderosa pine forests, northern Arizona, USA.

    Science.gov (United States)

    Kalies, E L; Dickson, B G; Chambers, C L; Covington, W W

    2012-01-01

    In western North American conifer forests, wildfires are increasing in frequency and severity due to heavy fuel loads that have accumulated after a century of fire suppression. Forest restoration treatments (e.g., thinning and/or burning) are being designed and implemented at large spatial and temporal scales in an effort to reduce fire risk and restore forest structure and function. In ponderosa pine (Pinus ponderosa) forests, predominantly open forest structure and a frequent, low-severity fire regime constituted the evolutionary environment for wildlife that persisted for thousands of years. Small mammals are important in forest ecosystems as prey and in affecting primary production and decomposition. During 2006-2009, we trapped eight species of small mammals at 294 sites in northern Arizona and used occupancy modeling to determine community responses to thinning and habitat features. The most important covariates in predicting small mammal occupancy were understory vegetation cover, large snags, and treatment. Our analysis identified two generalist species found at relatively high occupancy rates across all sites, four open-forest species that responded positively to treatment, and two dense-forest species that responded negatively to treatment unless specific habitat features were retained. Our results indicate that all eight small mammal species can benefit from restoration treatments, particularly if aspects of their evolutionary environment (e.g., large trees, snags, woody debris) are restored. The occupancy modeling approach we used resulted in precise species-level estimates of occupancy in response to habitat attributes for a greater number of small mammal species than in other comparable studies. We recommend our approach for other studies faced with high variability and broad spatial and temporal scales in assessing impacts of treatments or habitat alteration on wildlife species. Moreover, since forest planning efforts are increasingly focusing on

  6. Forest thinning and soil respiration in a ponderosa pine plantation in the Sierra Nevada.

    Science.gov (United States)

    Tang, Jianwu; Qi, Ye; Xu, Ming; Misson, Laurent; Goldstein, Allen H

    2005-01-01

    Soil respiration is controlled by soil temperature, soil water, fine roots, microbial activity, and soil physical and chemical properties. Forest thinning changes soil temperature, soil water content, and root density and activity, and thus changes soil respiration. We measured soil respiration monthly and soil temperature and volumetric soil water continuously in a young ponderosa pine (Pinus ponderosa Dougl. ex P. Laws. & C. Laws.) plantation in the Sierra Nevada Mountains in California from June 1998 to May 2000 (before a thinning that removed 30% of the biomass), and from May to December 2001 (after thinning). Thinning increased the spatial homogeneity of soil temperature and respiration. We conducted a multivariate analysis with two independent variables of soil temperature and water and a categorical variable representing the thinning event to simulate soil respiration and assess the effect of thinning. Thinning did not change the sensitivity of soil respiration to temperature or to water, but decreased total soil respiration by 13% at a given temperature and water content. This decrease in soil respiration was likely associated with the decrease in root density after thinning. With a model driven by continuous soil temperature and water time series, we estimated that total soil respiration was 948, 949 and 831 g C m(-2) year(-1) in the years 1999, 2000 and 2001, respectively. Although thinning reduced soil respiration at a given temperature and water content, because of natural climate variability and the thinning effect on soil temperature and water, actual cumulative soil respiration showed no clear trend following thinning. We conclude that the effect of forest thinning on soil respiration is the combined result of a decrease in root respiration, an increase in soil organic matter, and changes in soil temperature and water due to both thinning and interannual climate variability.

  7. Ranking Thinning Potential of Lodgepole Pine Stands

    OpenAIRE

    United States Department of Agriculture, Forest Service

    1987-01-01

    This paper presents models for predicting edge-response of dominant and codominant trees to clearing. Procedures are given for converting predictions to a thinning response index, for ranking stands for thinning priority. Data requirements, sampling suggestions, examples of application, and suggestions for management use are included to facilitate use as a field guide.

  8. Satellite Image-based Estimates of Snow Water Equivalence in Restored Ponderosa Pine Forests in Northern Arizona

    Science.gov (United States)

    Sankey, T.; Springer, A. E.; O'Donnell, F. C.; Donald, J.; McVay, J.; Masek Lopez, S.

    2014-12-01

    The U.S. Forest Service plans to conduct forest restoration treatments through the Four Forest Restoration Initiative (4FRI) on hundreds of thousands of acres of ponderosa pine forest in northern Arizona over the next 20 years with the goals of reducing wildfire hazard and improving forest health. The 4FRI's key objective is to thin and burn the forests to create within-stand openings that "promote snowpack accumulation and retention which benefit groundwater recharge and watershed processes at the fine (1 to 10 acres) scale". However, little is known about how these openings created by restoration treatments affect snow water equivalence (SWE) and soil moisture, which are key parts of the water balance that greatly influence water availability for healthy trees and for downstream water users in the Sonoran Desert. We have examined forest canopy cover by calculating a Normalized Difference Vegetation Index (NDVI), a key indicator of green vegetation cover, using Landsat satellite data. We have then compared NDVI between treatments at our study sites in northern Arizona and have found statistically significant differences in tree canopy cover between treatments. The control units have significantly greater forest canopy cover than the treated units. The thinned units also have significantly greater tree canopy cover than the thin-and-burn units. Winter season Landsat images have also been analyzed to calculate Normalized Difference Snow Index (NDSI), a key indicator of snow water equivalence and snow accumulation at the treated and untreated forests. The NDSI values from these dates are examined to determine if snow accumulation and snow water equivalence vary between treatments at our study sites. NDSI is significantly greater at the treated units than the control units. In particular, the thinned forest units have significantly greater snow cover than the control units. Our results indicate that forest restoration treatments result in increased snow pack

  9. The legacy of attack: implications of high phloem resin monoterpene levels in lodgepole pines following mass attack by mountain pine beetle, Dendroctonus ponderosae Hopkins.

    Science.gov (United States)

    Clark, E L; Huber, D P W; Carroll, A L

    2012-04-01

    The mountain pine beetle (Dendroctonus ponderosae Hopkins) is the most serious pest of pines (Pinus) in western North America. Host pines protect themselves from attack by producing a complex mixture of terpenes in their resin. We sampled lodgepole pine (Pinus contorta variety latifolia) phloem resin at four widely separated locations in the interior of British Columbia, Canada, both just before (beginning of July) and substantially after (end of August) the mountain pine beetle dispersal period. The sampled trees then were observed the next spring for evidence of survival, and the levels of seven resin monoterpenes were compared between July and August samples. Trees that did not survive consistently had significantly higher phloem resin monoterpene levels at the end of August compared with levels in July. Trees that did survive mainly did not exhibit a significant difference between the two sample dates. The accumulation of copious defense-related secondary metabolites in the resin of mountain pine beetle-killed lodgepole pine has important implications for describing the environmental niche that the beetle offspring survive in as well as that of parasitoids, predators, and other associates.

  10. Measuring the Effects of Disturbance & Climate on the CO2 & Energy Exchange of Ponderosa Pine Forests in the Pacific Northwest: Integration of Eddy Flux, Plant and Soil Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Beverly E. Law; Larry Mahrt

    2007-01-05

    The goal is to quantify and understand the influence of climate and disturbance on ecosystem processes and thus net carbon uptake by forests. The objective is to combine tower and ground-based observations to quantify the effects of disturbance on processes controlling carbon storage and CO{sub 2} and energy exchange in varying climatic conditions. Specific objectives are: (1) Investigate the effects of logging and fire on carbon storage and carbon dioxide and energy exchange in chronosequences of ponderosa pine, using consistent methodology; (2) Determine key environmental factors controlling carbon storage and carbon dioxide and energy exchange in these forests through a combination of measurements and process modeling; and (3) Assess spatial variation of the concentrations and transport in complex terrain. The eddy covariance method is used for measurements of CO2, water vapor, and energy exchanges in a chronosequence of ponderosa pine forests (burned in 2002 wildfire, 10 year-old stand, 90 year-old mature stand). The mature stand has been an AmeriFlux site since 2000 (following previous flux sites in young and old stands initiated in 1996). In addition to the eddy covariance measurements, a large suite of biological processes and ecosystem properties are determined for the purpose of developing independent forest carbon budgets and NEP estimates; these include photosynthesis, stand respiration, soil CO{sub 2} fluxes, annual litterfall, foliar chemistry, and bole increment, and soil organic matter among other parameters. The measurements are being integrated and evaluated with two ecosystem models (BIOME-BGC and SPA). Such analyses are needed to assess regional terrestrial ecosystem carbon budgets. The results will contribute scientific understanding of carbon processes, and will provide comprehensive data sets for forest managers and those preparing national carbon inventories to use in assessments of carbon sequestration in relation to interannual climate

  11. Trends in Snag Populations in Drought-Stressed Mixed-Conifer and Ponderosa Pine Forests (1997–2007

    Directory of Open Access Journals (Sweden)

    Joseph L. Ganey

    2012-01-01

    Full Text Available Snags provide important biological legacies, resources for numerous species of native wildlife, and contribute to decay dynamics and ecological processes in forested ecosystems. We monitored trends in snag populations from 1997 to 2007 in drought-stressed mixed-conifer and ponderosa pine (Pinus ponderosa Dougl. ex Laws forests, northern Arizona. Median snag density increased by 75 and 90% in mixed-conifer and ponderosa pine forests, respectively, over this time period. Increased snag density was driven primarily by a large pulse in drought-mediated tree mortality from 2002 to 2007, following a smaller pulse from 1997 to 2002. Decay-class composition and size-class composition of snag populations changed in both forest types, and species composition changed in mixed-conifer forest. Increases in snag abundance may benefit some species of native wildlife in the short-term by providing increased foraging and nesting resources, but these increases may be unsustainable in the long term. Observed changes in snag recruitment and fall rates during the study illustrate the difficulty involved in modeling dynamics of those populations in an era of climate change and changing land management practices.

  12. An experimental demonstration of stem damage as a predictor of fire-caused mortality for ponderosa pine

    Science.gov (United States)

    van Mantgem, P.; Schwartz, M.

    2004-01-01

    We subjected 159 small ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) to treatments designed to test the relative importance of stem damage as a predictor of postfire mortality. The treatments consisted of a group with the basal bark artificially thinned, a second group with fuels removed from the base of the stem, and an untreated control. Following prescribed burning, crown scorch severity was equivalent among the groups. Postfire mortality was significantly less frequent in the fuels removal group than in the bark removal and control groups. No model of mortality for the fuels removal group was possible, because dead trees constituted trees. Mortality in the bark removal group was best predicted by crown scorch and stem scorch severity, whereas death in the control group was predicted by crown scorch severity and bark thickness. The relative lack of mortality in the fuels removal group and the increased sensitivity to stem damage in the bark removal group suggest that stem damage is a critical determinant of postfire mortality for small ponderosa pine.

  13. Morphological features of Camarosporium pini – the fungus associated to health state degradation in Austrian and Ponderosa pine

    Directory of Open Access Journals (Sweden)

    Ivanová Helena

    2017-06-01

    Full Text Available The subject of this study is escalated occurrence of the pathogenic fungus Camarosporium pini in the needle tissue of symptomatic trees P. nigra and P. ponderosa var. jeffreyi growing in urbanized settings and parks. C. pini induces severe infections and initiates a blight and premature loss of second-year foliage in pine trees. The fungus was identified microscopically and on base of morphological keys. The affected needles displayed a distinct bluish-grey necrotic band in the centre. On the surface of infected needles, there were formed pycnidia producing brown, oval conidia with three transversal and one or two vertical walls. Disease symptoms, some important characteristics in pure culture, and distinctive morphological features of C. pini associated to the health state degradation in Austrian and Ponderosa pine are described and compared. Cumulative effects of these stressful biotic and various abiotic factors may explain the current situation concerning the decline in the P. nigra and P. ponderosa var. jeffreyi in Slovakia.

  14. Adaptability to climate change in forestry species: drought effects on growth and wood anatomy of ponderosa pines growing at different competition levels

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, M. E.; Gyenge, J. E.; Urquiza, M. M.; Varela, S.

    2012-11-01

    More stressful conditions are expected due to climatic change in several regions, including Patagonia, South-America. In this region, there are no studies about the impact of severe drought events on growth and wood characteristics of the most planted forestry species, Pinus ponderosa (Doug. ex-Laws). The objective of this study was to quantify the effect of a severe drought event on annual stem growth and functional wood anatomy of pines growing at different plantation densities aiming to understand how management practices can help to increase their adaptability to climate change. Growth magnitude and period, specific hydraulic conductivity, and anatomical traits (early- and late wood proportion, lumen diameter, cell-wall thickness, tracheid length and bordered pit dimensions) were measured in the ring 2008-2009, which was formed during drought conditions. This drought event decreased annual stem growth by 30-38% and 58-65% respect to previous mean growth, in open vs. closed stand trees, respectively, indicating a higher sensitivity of the latter, which is opposite to reports from the same species growing in managed native forests in USA. Some wood anatomical variables did differ in more water stressed trees (lower cell wall thickness of early wood cells and higher proportion of small-lumen cells in late wood), which in turn did not affect wood function (hydraulic conductivity and resistance to implosion). Other anatomical variables (tracheid length, pit dimensions, early- and late wood proportion, lumen diameter of early wood cells) did not differ between tree sizes and plantation density. The results suggest that severe drought affects differentially the amount but not the function and quality of formed wood in ponderosa pine growing at different competition levels. (Author) 41 refs.

  15. Isozyme markers associated with O3 tolerance indicate shift in genetic structure of ponderosa and Jeffrey pine in Sequoia National Park, California

    International Nuclear Information System (INIS)

    Staszak, J.; Grulke, N.E.; Marrett, M.J.; Prus-Glowacki, W.

    2007-01-01

    Effects of canopy ozone (O 3 ) exposure and signatures of genetic structure using isozyme markers associated with O 3 tolerance were analyzed in ∼20-, ∼80-, and >200-yr-old ponderosa (Pinus ponderosa Dougl. ex Laws.) and Jeffrey pine (Pinus jeffreyi Grev. and Balf.) in Sequoia National Park, California. For both species, the number of alleles and genotypes per loci was higher in parental trees relative to saplings. In ponderosa pine, the heterozygosity value increased, and the fixation index indicated reduction of homozygosity with increasing tree age class. The opposite tendencies were observed for Jeffrey pine. Utilizing canopy attributes known to be responsive to O 3 exposure, ponderosa pine was more symptomatic than Jeffrey pine, and saplings were more symptomatic than old growth trees. We suggest that these trends are related to differing sensitivity of the two species to O 3 exposure, and to higher O 3 exposures and drought stress that younger trees may have experienced during germination and establishment. - Genetic variation in isozyme markers associated with ozone tolerance differed between parental trees and their progeny in two closely related species of yellow pine

  16. Isozyme markers associated with O{sub 3} tolerance indicate shift in genetic structure of ponderosa and Jeffrey pine in Sequoia National Park, California

    Energy Technology Data Exchange (ETDEWEB)

    Staszak, J. [A Mickiewicz University, Genetics Department, ul. Umultowska 89, 61-614 Poznan (Poland); Grulke, N.E. [USDA Forest Service, 4955 Canyon Crest Drive, Riverside, CA 92507 (United States)], E-mail: ngrulke@fs.fed.us; Marrett, M.J. [5184 Tower Road, Riverside, CA 92506 (United States); Prus-Glowacki, W. [A Mickiewicz University, Genetics Department, ul. Umultowska 89, 61-614 Poznan (Poland)

    2007-10-15

    Effects of canopy ozone (O{sub 3}) exposure and signatures of genetic structure using isozyme markers associated with O{sub 3} tolerance were analyzed in {approx}20-, {approx}80-, and >200-yr-old ponderosa (Pinus ponderosa Dougl. ex Laws.) and Jeffrey pine (Pinus jeffreyi Grev. and Balf.) in Sequoia National Park, California. For both species, the number of alleles and genotypes per loci was higher in parental trees relative to saplings. In ponderosa pine, the heterozygosity value increased, and the fixation index indicated reduction of homozygosity with increasing tree age class. The opposite tendencies were observed for Jeffrey pine. Utilizing canopy attributes known to be responsive to O{sub 3} exposure, ponderosa pine was more symptomatic than Jeffrey pine, and saplings were more symptomatic than old growth trees. We suggest that these trends are related to differing sensitivity of the two species to O{sub 3} exposure, and to higher O{sub 3} exposures and drought stress that younger trees may have experienced during germination and establishment. - Genetic variation in isozyme markers associated with ozone tolerance differed between parental trees and their progeny in two closely related species of yellow pine.

  17. Forest Fire Smoldering Emissions from Ponderosa Pine Duff in Central Washington

    Science.gov (United States)

    Baker, S. P.; Lincoln, E.; Page, W.; Richardson, M.

    2017-12-01

    Forest fire smoldering combustion is a significant contribution to pollution and carbon emissions. Smoldering combustion produces the majority of carbon monoxide (CO), methane (CH4), volatile organic compounds (VOC), and fine particulate matter (PM2.5) emitted by forest fires when it occurs. The emission factor for PM2.5 and many VOCs are correlated with the modified combustion efficiency (MCE), which is the ratio of CO2 emitted, to the sum of emitted CO2 and CO. MCE is a measure of the relative ratio of flaming and smoldering combustion, but its relationship to the physical fire process is poorly studied. We measured carbon emission rates and individual emission factors for CO, CO2, CH4, and VOC's from smoldering combustion on Ponderosa pine /Douglas-Fir forest sites in central Washington. The emission factor results are linked with concurrent thermal measurements made at various depths in the duff and surface IR camera imagery. The MCE value ranged from .80 to .91 and are correlated with emission factors for 24 carbon compounds. Other data collected were fuel moistures and duff temperatures at depth increments. This goal of this research is the creation of a database to better predict the impacts of air pollution resulting from burns leading to smoldering combustion.

  18. Net Ecosystem Fluxes of Hydrocarbons from a Ponderosa Pine Forest in Colorado

    Science.gov (United States)

    Rhew, R. C.; Turnipseed, A. A.; Ortega, J. V.; Smith, J. N.; Guenther, A. B.; Shen, S.; Martinez, L.; Koss, A.; Warneke, C.; De Gouw, J. A.; Deventer, M. J.

    2015-12-01

    Light (C2-C4) alkenes, light alkanes and isoprene (C5H8) are non-methane hydrocarbons that play important roles in the photochemical production of tropospheric ozone and in the formation of secondary organic aerosols. Natural terrestrial fluxes of the light hydrocarbons are poorly characterized, with global emission estimates based on limited field measurements. In 2014, net fluxes of these compounds were measured at the Manitou Experimental Forest Observatory, a semi-arid ponderosa pine forest in the Colorado Rocky Mountains and site of the prior BEACHON campaigns. Three field intensives were conducted between June 17 and August 10, 2014. Net ecosystem flux measurements utilized a relaxed eddy accumulation system coupled to an automated gas chromatograph. Summertime average emissions of ethene and propene were up to 90% larger than those observed from a temperate deciduous forest. Ethene and propene fluxes were also correlated to each other, similar to the deciduous forest study. Emissions of isoprene were small, as expected for a coniferous forest, and these fluxes were not correlated with either ethene or propene. Unexpected emissions of light alkanes were also observed, and these showed a distinct diurnal cycle. Understory flux measurements allowed for the partitioning of fluxes between the surface and the canopy. Full results from the three field intensives will be compared with environmental variables in order to parameterize the fluxes for use in modeling emissions.

  19. Ethene, propene, butene and isoprene emissions from a ponderosa pine forest measured by relaxed eddy accumulation

    Science.gov (United States)

    Rhew, Robert C.; Deventer, Malte Julian; Turnipseed, Andrew A.; Warneke, Carsten; Ortega, John; Shen, Steve; Martinez, Luis; Koss, Abigail; Lerner, Brian M.; Gilman, Jessica B.; Smith, James N.; Guenther, Alex B.; de Gouw, Joost A.

    2017-11-01

    Alkenes are reactive hydrocarbons that influence local and regional atmospheric chemistry by playing important roles in the photochemical production of tropospheric ozone and in the formation of secondary organic aerosols. The simplest alkene, ethene (ethylene), is a major plant hormone and ripening agent for agricultural commodities. The group of light alkenes (C2-C4) originates from both biogenic and anthropogenic sources, but their biogenic sources are poorly characterized, with limited field-based flux observations. Here we report net ecosystem fluxes of light alkenes and isoprene from a semiarid ponderosa pine forest in the Rocky Mountains of Colorado, USA using the relaxed eddy accumulation (REA) technique during the summer of 2014. Ethene, propene, butene and isoprene emissions have strong diurnal cycles, with median daytime fluxes of 123, 95, 39 and 17 µg m-2 h-1, respectively. The fluxes were correlated with each other, followed general ecosystem trends of CO2 and water vapor, and showed similar sunlight and temperature response curves as other biogenic VOCs. The May through October flux, based on measurements and modeling, averaged 62, 52, 24 and 18 µg m-2 h-1 for ethene, propene, butene and isoprene, respectively. The light alkenes contribute significantly to the overall biogenic source of reactive hydrocarbons: roughly 18 % of the dominant biogenic VOC, 2-methyl-3-buten-2-ol. The measured ecosystem scale fluxes are 40-80 % larger than estimates used for global emissions models for this type of ecosystem.

  20. Transmission components of solar radiation in pine stands in relation to climatic and stand variables

    Science.gov (United States)

    Robert A. Muller

    1971-01-01

    In a new approach, transmission was studied by relating to stand biomass the ratio of incoming solar radiation beneath tree crowns to that within the atmosphere. Several assumptions were used to estimate analytically the various ways in which solar radiation penetrates through crowns of three pine species in northern California. Sunflecks accounted for much of the...

  1. Post-harvest seedling recruitment following mountain pine beetle infestation of Colorado lodgepole pine stands: A comparison using historic survey records

    Science.gov (United States)

    Byron J. Collins; Charles C. Rhoades; Jeffrey Underhill; Robert M. Hubbard

    2010-01-01

    The extent and severity of overstory lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) mortality from mountain pine beetle (Dendroctonus ponderosae Hopkins) has created management concerns associated with forest regeneration, wildfire risk, human safety, and scenic, wildlife, and watershed resources in western North America. Owing to the unprecedented...

  2. Comparison of different real time VOC measurement techniques in a ponderosa pine forest

    Directory of Open Access Journals (Sweden)

    L. Kaser

    2013-03-01

    Full Text Available Volatile organic compound (VOC mixing ratios measured by five independent instruments are compared at a forested site dominated by ponderosa pine (Pinus Ponderosa during the BEACHON-ROCS field study in summer 2010. The instruments included a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-TOF-MS, a Proton Transfer Reaction Quadrupole Mass Spectrometer (PTR-MS, a Fast Online Gas-Chromatograph coupled to a Mass Spectrometer (GC/MS; TOGA, a Thermal Dissociation Chemical Ionization Mass Spectrometer (PAN-CIMS and a Fiber Laser-Induced Fluorescence Instrument (FILIF. The species discussed in this comparison include the most important biogenic VOCs and a selected suite of oxygenated VOCs that are thought to dominate the VOC reactivity at this particular site as well as typical anthropogenic VOCs that showed low mixing ratios at this site. Good agreement was observed for methanol, the sum of the oxygenated hemiterpene 2-methyl-3-buten-2-ol (MBO and the hemiterpene isoprene, acetaldehyde, the sum of acetone and propanal, benzene and the sum of methyl ethyl ketone (MEK and butanal. Measurements of the above VOCs conducted by different instruments agree within 20%. The ability to differentiate the presence of toluene and cymene by PTR-TOF-MS is tested based on a comparison with GC-MS measurements, suggesting a study-average relative contribution of 74% for toluene and 26% for cymene. Similarly, 2-hydroxy-2-methylpropanal (HMPR is found to interfere with the sum of methyl vinyl ketone and methacrolein (MVK + MAC using PTR-(TOF-MS at this site. A study-average relative contribution of 85% for MVK + MAC and 15% for HMPR was determined. The sum of monoterpenes measured by PTR-MS and PTR-TOF-MS was generally 20–25% higher than the sum of speciated monoterpenes measured by TOGA, which included α-pinene, β-pinene, camphene, carene, myrcene, limonene, cineole as well as other terpenes. However, this difference is consistent throughout the study

  3. Pelletized ponderosa pine bark for adsorption of toxic heavy metals from water

    Directory of Open Access Journals (Sweden)

    Tshabalala, M. A.

    2007-02-01

    Full Text Available Bark flour from ponderosa pine (Pinus ponderosa was consolidated into pellets using citric acid as cross-linking agent. The pellets were evaluated for removal of toxic heavy metals from synthetic aqueous solutions. When soaked in water, pellets did not leach tannins, and they showed high adsorption capacity for Cu(II, Zn(II, Cd(II, and Ni(II under both equilibrium and dynamic adsorption conditions. The experimental data for Cd(II and Zn(II showed a better fit to the Langmuir than to the Freundlich isotherm. The Cu(II data best fit the Freundlich isotherm, and the Ni(II data fitted both Freundlich and Langmuir isotherms equally. According to the Freundlich constant KF, adsorption capacity of pelletized bark for the metal ions in aqueous solution, pH 5.1 ± 0.2, followed the order Cd(II > Cu(II > Zn(II >> Ni(II; according to the Langmuir constant b, adsorption affinity followed the order Cd(II >> Cu(II ≈ Zn(II >> Ni(II. Although data from dynamic column adsorption experiments did not show a good fit to the Thomas kinetic adsorption model, estimates of sorption affinity series of the metal ions on pelletized bark derived from this model were not consistent with the series derived from the Langmuir or Freundlich isotherms and followed the order Cu(II > Zn(II ≈ Cd(II > Ni(II. According to the Thomas kinetic model, the theoretical maximum amounts of metal that can be sorbed on the pelletized bark in a column at influent concentration of ≈10 mg/L and flow rate = 5 mL/min were estimated to be 57, 53, 50, and 27 mg/g for copper, zinc, cadmium, and nickel, respectively. This study demonstrated the potential for converting low-cost bark residues to value-added sorbents using starting materials and chemicals derived from renewable resources. These sorbents can be applied in the removal of toxic heavy metals from waste streams with heavy metal ion concentrations of up to 100 mg/L in the case of Cu(II.

  4. Basal area or stocking percent: which works best in controlling density in natural shortleaf pine stands

    Science.gov (United States)

    Ivan L. Sander

    1986-01-01

    Results from a shortleaf pine thinning study in Missouri show that continually thinning a stand to the same basal area will eventually create an understocked stand and reduce yields. Using stocking percent to control thinning intensity allows basal area to increase as stands get older. The best yield should occur when shortleaf pine is repeatedly thinned to 60 percent...

  5. Distribution of black carbon in Ponderosa pine litter and soils following the High Park wildfire

    Science.gov (United States)

    Boot, C. M.; Haddix, M.; Paustian, K.; Cotrufo, M. F.

    2014-12-01

    Black carbon (BC), the heterogeneous product of burned biomass, is a critical component in the global carbon cycle, yet timescales and mechanisms for incorporation into the soil profile are not well understood. The High Park Fire, which took place in northwestern Colorado in the summer of 2012, provided an opportunity to study the effects of both fire intenstiy and geomorphology on properties of carbon (C), nitrogen (N), and BC in the Cache La Poudre River drainage. We sampled montane Ponderosa pine litter, 0-5 cm soils, and 5-15 cm soils four months post-fire in order to examine the effects of slope and burn intensity on %C, C stocks, %N and black carbon (g kg-1 C, and g m-2). We developed and implemented the benzene polycarboxylic acid (BPCA) method for quantifying BC. With regard to slope, we found that steeper slopes had higher C : N than shallow slopes, but that there was no difference in black carbon content or stocks. BC content was greatest in the litter in burned sites (19 g kg-1 C), while BC stocks were greatest in the 5-15 cm subsurface soils (23 g m-2). At the time of sampling, none of the BC deposited on the land surface post-fire had been incorporated into to either the 0-5 cm or 5-15 cm soil layers. The ratio of B5CA : B6CA (less condensed to more condensed BC) indicated there was significantly more older, more processed BC at depth. Total BC soil stocks were relatively low compared to other fire-prone grassland and boreal forest systems, indicating most of the BC produced in this system is likely transported off the surface through erosion events. Future work examining mechanisms for BC transport will be required for understanding the role BC plays in the global carbon cycle.

  6. Development of genetic diversity, differentiation and structure over 500 years in four ponderosa pine populations.

    Science.gov (United States)

    Lesser, M R; Parchman, T L; Jackson, S T

    2013-05-01

    Population history plays an important role in shaping contemporary levels of genetic variation and geographic structure. This is especially true in small, isolated range-margin populations, where effects of inbreeding, genetic drift and gene flow may be more pronounced than in large continuous populations. Effects of landscape fragmentation and isolation distance may have implications for persistence of range-margin populations if they are demographic sinks. We studied four small, disjunct populations of ponderosa pine over a 500-year period. We coupled demographic data obtained through dendroecological methods with microsatellite data to discern how and when contemporary levels of allelic diversity, among and within-population levels of differentiation, and geographic structure, arose. Alleles accumulated rapidly following initial colonization, demonstrating proportionally high levels of gene flow into the populations. At population sizes of approximately 100 individuals, allele accumulation saturated. Levels of genetic differentiation among populations (F(ST) and Jost's D(est)) and diversity within populations (F(IS)) remained stable through time. There was no evidence of geographic genetic structure at any time in the populations' history. Proportionally, high gene flow in the early stages of population growth resulted in rapid accumulation of alleles and quickly created relatively homogenous genetic patterns among populations. Our study demonstrates that contemporary levels of genetic diversity were formed quickly and early in population development. How contemporary genetic diversity accumulates over time is a key facet of understanding population growth and development. This is especially relevant given the extent and speed at which species ranges are predicted to shift in the coming century. © 2013 Blackwell Publishing Ltd.

  7. Eddy covariance methane measurements at a Ponderosa pine plantation in California

    Directory of Open Access Journals (Sweden)

    T. Röckmann

    2009-11-01

    Full Text Available Long term methane flux measurements have been mostly performed with plant or soil enclosure techniques on specific components of an ecosystem. New fast response methane analyzers make it possible to use the eddy covariance (EC technique instead. The EC technique is advantageous because it allows continuous flux measurements integrating over a larger and more representative area including the complete ecosystem, and allows fluxes to be observed as environmental conditions change naturally without disturbance. We deployed the closed-path Fast Methane analyzer (FMA from Los Gatos Research Ltd and demonstrate its performance for EC measurements at a Ponderosa pine plantation at the Blodgett Forest site in central California. The fluctuations of the CH4 concentration measured at 10 Hz appear to be small and their standard deviation is comparable to the magnitude of the signal noise (±5 ppbv. Consequently, the power spectra typically have a white noise signature at the high frequency end (a slope of +1. Nevertheless, in the frequency range important for turbulent exchange, the cospectra of CH4 compare very well with all other scalar cospectra confirming the quality of the FMA measurements are good for the EC technique. We furthermore evaluate the complications of combined open and closed-path measurements when applying the Webb-Pearman-Leuning (WPL corrections (Webb et al., 1980 and the consequences of a phase lag between the water vapor and methane signal inside the closed path system. The results of diurnal variations of CH4 concentrations and fluxes are summarized and compared to the monthly results of process-based model calculations.

  8. Eddy covariance fluxes of acyl peroxy nitrates (PAN, PPN and MPAN above a Ponderosa pine forest

    Directory of Open Access Journals (Sweden)

    G. M. Wolfe

    2009-01-01

    Full Text Available During the Biosphere Effects on AeRosols and Photochemistry EXperiment 2007 (BEARPEX-2007, we observed eddy covariance (EC fluxes of speciated acyl peroxy nitrates (APNs, including peroxyacetyl nitrate (PAN, peroxypropionyl nitrate (PPN and peroxymethacryloyl nitrate (MPAN, above a Ponderosa pine forest in the western Sierra Nevada. All APN fluxes are net downward during the day, with a median midday PAN exchange velocity of −0.3 cm s−1; nighttime storage-corrected APN EC fluxes are smaller than daytime fluxes but still downward. Analysis with a standard resistance model shows that loss of PAN to the canopy is not controlled by turbulent or molecular diffusion. Stomatal uptake can account for 25 to 50% of the observed downward PAN flux. Vertical gradients in the PAN thermal decomposition (TD rate explain a similar fraction of the flux, suggesting that a significant portion of the PAN flux into the forest results from chemical processes in the canopy. The remaining "unidentified" portion of the net PAN flux (~15% is ascribed to deposition or reactive uptake on non-stomatal surfaces (e.g. leaf cuticles or soil. Shifts in temperature, moisture and ecosystem activity during the summer – fall transition alter the relative contribution of stomatal uptake, non-stomatal uptake and thermochemical gradients to the net PAN flux. Daytime PAN and MPAN exchange velocities are a factor of 3 smaller than those of PPN during the first two weeks of the measurement period, consistent with strong intra-canopy chemical production of PAN and MPAN during this period. Depositional loss of APNs can be 3–21% of the gross gas-phase TD loss depending on temperature. As a source of nitrogen to the biosphere, PAN deposition represents approximately 4–19% of that due to dry deposition of nitric acid at this site.

  9. Masting in ponderosa pine: comparisons of pollen and seed over space and time.

    Science.gov (United States)

    Mooney, Kailen A; Linhart, Yan B; Snyder, Marc A

    2011-03-01

    Many plant species exhibit variable and synchronized reproduction, or masting, but less is known of the spatial scale of synchrony, effects of climate, or differences between patterns of pollen and seed production. We monitored pollen and seed cone production for seven Pinus ponderosa populations (607 trees) separated by up to 28 km and 1,350 m in elevation in Boulder County, Colorado, USA for periods of 4-31 years for a mean per site of 8.7 years for pollen and 12.1 for seed cone production. We also analyzed climate data and a published dataset on 21 years of seed production for an eighth population (Manitou) 100 km away. Individual trees showed high inter-annual variation in reproduction. Synchrony was high within populations, but quickly became asynchronous among populations with a combination of increasing distance and elevational difference. Inter-annual variation in temperature and precipitation had differing influences on seed production for Boulder County and Manitou. We speculate that geographically variable effects of climate on reproduction arise from environmental heterogeneity and population genetic differentiation, which in turn result in localized synchrony. Although individual pines produce pollen and seed, only one-third of the covariation within trees was shared. As compared to seed cones, pollen had lower inter-annual variation at the level of the individual tree and was more synchronous. However, pollen and seed production were similar with respect to inter-annual variation at the population level, spatial scales of synchrony and associations with climate. Our results show that strong masting can occur at a localized scale, and that reproductive patterns can differ between pollen and seed cone production in a hermaphroditic plant.

  10. Modern fire regime resembles historical fire regime in a ponderosa pine forest on Native American land

    Science.gov (United States)

    Amanda B. Stan; Peter Z. Fule; Kathryn B. Ireland; Jamie S. Sanderlin

    2014-01-01

    Forests on tribal lands in the western United States have seen the return of low-intensity surface fires for several decades longer than forests on non-tribal lands. We examined the surface fire regime in a ponderosa pinedominated (Pinus ponderosa) forest on the Hualapai tribal lands in the south-western United States. Using fire-scarred trees, we inferred temporal (...

  11. EFFECTS OF CLIMATE VARIABILITY ON THE CARBON DIOXIDE, WATER, AND SENSIBLE HEAT FLUXES ABOVE A PONDEROSA PINE PLANTATION IN THE SIERRA NEVADA, CA. (R826601)

    Science.gov (United States)

    AbstractFluxes of CO2, water vapor, and sensible heat were measured by the eddy covariance method above a young ponderosa pine plantation in the Sierra Nevada Mountains (CA) over two growing seasons (1 June¯10 September 1997 and 1 May&#...

  12. Carbon and nitrogen cycling in southwestern ponderosa fine forests

    Science.gov (United States)

    Stephen C. Hart; Paul C. Selmants; Sarah I. Boyle; Steven T. Overby

    2007-01-01

    Ponderosa pine forests of the southwestern United States were historically characterized by relatively open, parklike stands with a bunchgrass-dominated understory. This forest structure was maintained by frequent, low-intensity surface fires. Heavy livestock grazing, fire suppression, and favorable weather conditions following Euro-American settlement in the late 19th...

  13. Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests

    Science.gov (United States)

    Robles, Marcos D.; Marshall, Robert M.; O'Donnell, Frances; Smith, Edward B.; Haney, Jeanmarie A.; Gori, David F.

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0–3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide. PMID

  14. Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests.

    Directory of Open Access Journals (Sweden)

    Marcos D Robles

    Full Text Available The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres of ponderosa pine (Pinus ponderosa forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment and modest when compared to mean annual runoff from the study watersheds (0-3%. Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

  15. Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests.

    Science.gov (United States)

    Robles, Marcos D; Marshall, Robert M; O'Donnell, Frances; Smith, Edward B; Haney, Jeanmarie A; Gori, David F

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0-3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

  16. Testing a hydraulic trait based model of stomatal control: results from a controlled drought experiment on aspen (Populus tremuloides, Michx.) and ponderosa pine (Pinus ponderosa, Douglas)

    Science.gov (United States)

    Love, D. M.; Venturas, M.; Sperry, J.; Wang, Y.; Anderegg, W.

    2017-12-01

    Modeling approaches for tree stomatal control often rely on empirical fitting to provide accurate estimates of whole tree transpiration (E) and assimilation (A), which are limited in their predictive power by the data envelope used to calibrate model parameters. Optimization based models hold promise as a means to predict stomatal behavior under novel climate conditions. We designed an experiment to test a hydraulic trait based optimization model, which predicts stomatal conductance from a gain/risk approach. Optimal stomatal conductance is expected to maximize the potential carbon gain by photosynthesis, and minimize the risk to hydraulic transport imposed by cavitation. The modeled risk to the hydraulic network is assessed from cavitation vulnerability curves, a commonly measured physiological trait in woody plant species. Over a growing season garden grown plots of aspen (Populus tremuloides, Michx.) and ponderosa pine (Pinus ponderosa, Douglas) were subjected to three distinct drought treatments (moderate, severe, severe with rehydration) relative to a control plot to test model predictions. Model outputs of predicted E, A, and xylem pressure can be directly compared to both continuous data (whole tree sapflux, soil moisture) and point measurements (leaf level E, A, xylem pressure). The model also predicts levels of whole tree hydraulic impairment expected to increase mortality risk. This threshold is used to estimate survivorship in the drought treatment plots. The model can be run at two scales, either entirely from climate (meteorological inputs, irrigation) or using the physiological measurements as a starting point. These data will be used to study model performance and utility, and aid in developing the model for larger scale applications.

  17. Using tree recruitment patterns and fire history to guide restoration of an unlogged ponderosa pine/Douglas-fir landscape in the southern Rocky Mountains after a century of fire suppression

    Science.gov (United States)

    Merrill R. Kaufmann; Laurie S. Huckaby; Paula J. Fornwalt; Jason M. Stoker; William H. Romme

    2003-01-01

    Tree age and fire history were studied in an unlogged ponderosa pine/Douglas-fir (Pinus ponderosa/Pseudotsuga menziesii) landscape in the Colorado Front Range mountains. These data were analysed to understand tree survival during fire and post-fire recruitment patterns after fire, as a basis for understanding the characteristics of, and restoration needs for, an...

  18. A whole stand growth and yield system for young longleaf pine plantations in Southwest Georgia

    Science.gov (United States)

    John R. Brooks; Steven B. Jack

    2006-01-01

    A whole stand growth and yield system for planted longleaf pine (Pinus palustris Mill.) was developed from permanent plot data collected annually over an 8 year period. The dataset consists of 12 intensively-managed longleaf pine plantations that are located in Lee, Worth, Mitchell, and Baker counties in southwest Georgia. Stand survival, dominant...

  19. Ecological restoration of an old-growth longleaf pine stand utilizing prescribed fire

    Science.gov (United States)

    J. Morgan Varner; John S. Kush; Ralph S. Meldahl

    2000-01-01

    Ecological restoration using prescribed fire has been underway for 3 years in an uncut, old-growth longleaf pine (Pinus palustris) stand located in south Alabama. The longleaf pine ecosystem requires frequent (once every 1-10 years) surface fire to prevent succesion to later several stages. Before this study began, this stand had not burned in >...

  20. Growth reductions in naturally regenerated southern pine stands in Alabama and Georgia

    Science.gov (United States)

    G.A. Ruark; C.E. Thomas; W.A. Bechtold; D.M. May

    1991-01-01

    Data from Forest Inventory and analysis (FIA) units of the USDA Forest Service were used to compare average annual stand-level basal area accretion onto survivor pines in naturally regenerated pine stands throughout Alabama and Georgia. Growth rates measured between 1972-82 were compared to growth rates during the previous 10-year survey cycle in each state. Separate...

  1. Rehabilitation of Understocked Loblolly-Shortleaf Pine Stands - II. Development of Intermediate and Suppressed Trees Following Release in Natural Stands

    Science.gov (United States)

    James B. Baker; Michael G. Shelton

    1998-01-01

    Development of 86 intermediate and suppressed loblolly pine (Pinus taeda L.) trees, that had been recently released from overtopping pines and hardwoods, was monitored over a 15 year period. The trees were growing in natural stands on good sites (site index = 90 ft at 50 years) that had been recently cut to stocking levels ranging from 10 to 50 percent. At time of...

  2. Distribution of black carbon in ponderosa pine forest floor and soils following the High Park wildfire

    Science.gov (United States)

    Boot, C. M.; Haddix, M.; Paustian, K.; Cotrufo, M. F.

    2015-05-01

    Biomass burning produces black carbon (BC), effectively transferring a fraction of the biomass C from an actively cycling pool to a passive C pool, which may be stored in the soil. Yet the timescales and mechanisms for incorporation of BC into the soil profile are not well understood. The High Park fire (HPF), which occurred in northwestern Colorado in the summer of 2012, provided an opportunity to study the effects of both fire severity and geomorphology on properties of carbon (C), nitrogen (N) and BC in the Cache La Poudre River drainage. We sampled montane ponderosa pine forest floor (litter plus O-horizon) and soils at 0-5 and 5-15 cm depth 4 months post-fire in order to examine the effects of slope and burn severity on %C, C stocks, %N and BC. We used the benzene polycarboxylic acid (BPCA) method for quantifying BC. With regard to slope, we found that steeper slopes had higher C : N than shallow slopes but that there was no difference in BPCA-C content or stocks. BC content was greatest in the forest floor at burned sites (19 g BPCA-C kg-1 C), while BC stocks were greatest in the 5-15 cm subsurface soils (23 g BPCA-C m-2). At the time of sampling, unburned and burned soils had equivalent BC content, indicating none of the BC deposited on the land surface post-fire had been incorporated into either the 0-5 or 5-15 cm soil layers. The ratio of B6CA : total BPCAs, an index of the degree of aromatic C condensation, suggested that BC in the 5-15 cm soil layer may have been formed at higher temperatures or experienced selective degradation relative to the forest floor and 0-5 cm soils. Total BC soil stocks were relatively low compared to other fire-prone grassland and boreal forest systems, indicating most of the BC produced in this system is likely lost, either through erosion events, degradation or translocation to deeper soils. Future work examining mechanisms for BC losses from forest soils will be required for understanding the role BC plays in the global

  3. Strategies for preventing invasive plant outbreaks after prescribed fire in ponderosa pine forest

    Science.gov (United States)

    Symstad, Amy J.; Newton, Wesley E.; Swanson, Daniel J.

    2014-01-01

    Land managers use prescribed fire to return a vital process to fire-adapted ecosystems, restore forest structure from a state altered by long-term fire suppression, and reduce wildfire intensity. However, fire often produces favorable conditions for invasive plant species, particularly if it is intense enough to reveal bare mineral soil and open previously closed canopies. Understanding the environmental or fire characteristics that explain post-fire invasive plant abundance would aid managers in efficiently finding and quickly responding to fire-caused infestations. To that end, we used an information-theoretic model-selection approach to assess the relative importance of abiotic environmental characteristics (topoedaphic position, distance from roads), pre-and post-fire biotic environmental characteristics (forest structure, understory vegetation, fuel load), and prescribed fire severity (measured in four different ways) in explaining invasive plant cover in ponderosa pine forest in South Dakota’s Black Hills. Environmental characteristics (distance from roads and post-fire forest structure) alone provided the most explanation of variation (26%) in post-fire cover of Verbascum thapsus (common mullein), but a combination of surface fire severity and environmental characteristics (pre-fire forest structure and distance from roads) explained 36–39% of the variation in post-fire cover of Cirsium arvense (Canada thistle) and all invasives together. For four species and all invasives together, their pre-fire cover explained more variation (26–82%) in post-fire cover than environmental and fire characteristics did, suggesting one strategy for reducing post-fire invasive outbreaks may be to find and control invasives before the fire. Finding them may be difficult, however, since pre-fire environmental characteristics explained only 20% of variation in pre-fire total invasive cover, and less for individual species. Thus, moderating fire intensity or targeting areas

  4. Ponderosa Pine Forest Restoration Treatment Longevity: Implications of Regeneration on Fire Hazard

    Directory of Open Access Journals (Sweden)

    Wade T. Tinkham

    2016-07-01

    Full Text Available Restoration of pine forests has become a priority for managers who are beginning to embrace ideas of highly heterogeneous forest structures that potentially encourages high levels of regeneration. This study utilizes stem-mapped stands to assess how simulated regeneration timing and magnitude influence longevity of reduced fire behavior by linking growth and yield model outputs to a crown fire prediction model. Treatment longevity was assessed as return time to within 10% of pre-treatment predicted wind speeds for the onset of passive (Torching and active (Crowning crown fire behavior. Treatment longevity in terms of Torching and Crowning was reduced 5 years for every 550 and 150 seedlings ha−1, respectively. Introducing regeneration as a single pulse further reduced Torching treatment longevity 10 years compared to other regeneration distributions. Crowning treatment longevity increased at higher site indices, where a 6 m increase in site index increased longevity 4.5 year. This result was contrary to expectations that canopy openings after treatments would close faster on higher productivity sites. Additionally, Torching longevity was influenced by the rate of crown recession, were reducing the recession rate decreased longevity in areas with higher site indices. These dependencies highlight a need for research exploring stand development in heterogeneous sites.

  5. Tree response and mountain pine beetle attack preference, reproduction, and emergence timing in mixed whitebark and lodgepole pines

    Science.gov (United States)

    Barbara J. Bentz; Celia Boone; Kenneth F. Raffa

    2015-01-01

    Mountain pine beetle (Dendroctonus ponderosae) is an important disturbance agent in Pinus ecosystems of western North America, historically causing significant tree mortality. Most recorded outbreaks have occurred in mid elevation lodgepole pine (Pinus contorta). In warm years, tree mortality also occurs at higher elevations in mixed species stands.

  6. Effect of climate variability and management practices on carbon, water and energy fluxes of a young Ponderosa pine plantation in the Sierra Nevada (CA)

    Science.gov (United States)

    Misson, L.; Tang, J.; McKay, M.; Goldstein, A. H.

    2003-04-01

    Despite the range and importance of semi-arid Ponderosa pine ecosystem in the United States, stand-scale fluxes of carbon, water and energy of these ecosystems have rarely been studied. Our research at the Blodgett Forest Research Station in the Sierra Nevada of California is advocated to better understand how these fluxes of a mid-elevation, young pine plantation vary interannually in response to climate variability, and how they are impacted by management practices such as shrub removal and thinning. Fluxes of CO2, H2O, and energy have been measured continuously since May 1999 by the eddy covariance method. Environmental parameters such as wind direction and speed, air temperature and humidity, net and photosynthetically active radiation, soil temperature, soil moisture, soil heat flux, rain, and atmospheric pressure are also monitored. Additional continuous measurements at the site have included O3 concentration and flux, and concentration and fluxes of a wide variety of volatile organic compounds. The data set covers periods characterized by various levels of drought stress. Shrub was removed in the spring 1999 and a precommercial thinning of 2/3 of the trees was applied in the spring 2000. Even during the winter, the young Ponderosa pine plantation at Blodgett acted mainly as a sink of carbon during the four years of measurement. The decrease of leaf area index and thus photosynthesis caused by thinning is the main factor that caused lower uptake, but increased respiration also occurred. These effects are limited in time and magnitude due to the rapidly increasing leaf area index after thinning. Beside this, the ability of this young pine plantation to act as a sink of carbon was also influenced by interannual variability of climate. Drought is a regular feature of the climate of California, making water availability the major controller of gas exchange in summer and fall. Freezing temperatures limit CO2 ecosystem uptake during the winter and tree growth in

  7. Extreme late-summer drought causes neutral annual carbon balance in southwestern ponderosa pine forests and grasslands

    International Nuclear Information System (INIS)

    Kolb, Thomas; Dore, Sabina; Montes-Helu, Mario

    2013-01-01

    We assessed the impacts of extreme late-summer drought on carbon balance in a semi-arid forest region in Arizona. To understand drought impacts over extremes of forest cover, we measured net ecosystem production (NEP), gross primary production (GPP), and total ecosystem respiration (TER) with eddy covariance over five years (2006–10) at an undisturbed ponderosa pine (Pinus ponderosa) forest and at a former forest converted to grassland by intense burning. Drought shifted annual NEP from a weak source of carbon to the atmosphere to a neutral carbon balance at the burned site and from a carbon sink to neutral at the undisturbed site. Carbon fluxes were particularly sensitive to drought in August. Drought shifted August NEP at the undisturbed site from sink to source because the reduction of GPP (70%) exceeded the reduction of TER (35%). At the burned site drought shifted August NEP from weak source to neutral because the reduction of TER (40%) exceeded the reduction of GPP (20%). These results show that the lack of forest recovery after burning and the exposure of undisturbed forests to late-summer drought reduce carbon sink strength and illustrate the high vulnerability of forest carbon sink strength in the southwest US to predicted increases in intense burning and precipitation variability. (letter)

  8. Extreme late-summer drought causes neutral annual carbon balance in southwestern ponderosa pine forests and grasslands

    Science.gov (United States)

    Kolb, Thomas; Dore, Sabina; Montes-Helu, Mario

    2013-03-01

    We assessed the impacts of extreme late-summer drought on carbon balance in a semi-arid forest region in Arizona. To understand drought impacts over extremes of forest cover, we measured net ecosystem production (NEP), gross primary production (GPP), and total ecosystem respiration (TER) with eddy covariance over five years (2006-10) at an undisturbed ponderosa pine (Pinus ponderosa) forest and at a former forest converted to grassland by intense burning. Drought shifted annual NEP from a weak source of carbon to the atmosphere to a neutral carbon balance at the burned site and from a carbon sink to neutral at the undisturbed site. Carbon fluxes were particularly sensitive to drought in August. Drought shifted August NEP at the undisturbed site from sink to source because the reduction of GPP (70%) exceeded the reduction of TER (35%). At the burned site drought shifted August NEP from weak source to neutral because the reduction of TER (40%) exceeded the reduction of GPP (20%). These results show that the lack of forest recovery after burning and the exposure of undisturbed forests to late-summer drought reduce carbon sink strength and illustrate the high vulnerability of forest carbon sink strength in the southwest US to predicted increases in intense burning and precipitation variability.

  9. Assessing the impact of a mountain pine beetle infestation on stand structure of lodgepole pine forests in Colorado using the Forest Inventory and Analysis Annual forest inventory

    Science.gov (United States)

    Michael T. Thompson

    2017-01-01

    The Forest Inventory and Analysis (FIA) annual inventory system began in Colorado in 2002, which coincided with the onset of a major mountain pine beetle (Dendroctonus ponderosae) epidemic. The mortality event, coupled with 11 years of annual inventory data, provided an opportunity to assess the usefulness of the FIA annual inventory system for quantifying the effects...

  10. FireWorks curriculum featuring ponderosa, lodgepole, and whitebark pine forests

    Science.gov (United States)

    Jane Kapler Smith; Nancy E. McMurray

    2000-01-01

    FireWorks is an educational program for students in grades 1-10. The program consists of the curriculum in this report and a trunk of laboratory materials, specimens, and reference materials. It provides interactive, hands-on activities for studying fire ecology, fire behavior, and the influences of people on three fire-dependent forest types - Pinus ponderosa...

  11. FOLIAR N RESPONSE OF PONDEROSA PINE SEEDLINGS TO ELEVATED CO2 AND O3

    Science.gov (United States)

    Interactions between needle N status and exposure to combined CO2 and O3 stresses were studied in Pinus ponderosa seedlings. The seedlings were grown for three years (April 1998 through March 2001) in outdoor chambers in native soils from eastern Oregon, and exposed to ambient ...

  12. Adaptability to climate change in forestry species: drought effects on growth and wood anatomy of ponderosa pines growing at different competition levels

    OpenAIRE

    Fernández, M.E.; Gyenge, J.E.; de Urquiza, M.M.; Varela, S.

    2012-01-01

    More stressful conditions are expected due to climatic change in several regions, including Patagonia, South-America. In this region, there are no studies about the impact of severe drought events on growth and wood characteristics of the most planted forestry species, Pinus ponderosa (Doug. ex-Laws). The objective of this study was to quantify the effect of a severe drought event on annual stem growth and functional wood anatomy of pines growing at different plantation densities aiming to un...

  13. Genetic variation of lodgepole pine, Pinus contorta var. latifolia, chemical and physical defenses that affect mountain pine beetle, Dendroctonus ponderosae, attack and tree mortality.

    Science.gov (United States)

    Ott, Daniel S; Yanchuk, Alvin D; Huber, Dezene P W; Wallin, Kimberly F

    2011-09-01

    Plant secondary chemistry is determined by both genetic and environmental factors, and while large intraspecific variation in secondary chemistry has been reported frequently, the levels of genetic variation of many secondary metabolites in forest trees in the context of potential resistance against pests have been rarely investigated. We examined the effect of tree genotype and environment/site on the variation in defensive secondary chemistry of lodgepole pine, Pinus contorta var. latifolia, against the fungus, Grosmannia clavigera (formerly known as Ophiostoma clavigerum), associated with the mountain pine beetle, Dendroctonus ponderosae. Terpenoids were analyzed in phloem samples from 887, 20-yr-old trees originating from 45 half-sibling families planted at two sites. Samples were collected both pre- and post-inoculation with G. clavigera. Significant variation in constitutive and induced terpenoid compounds was attributed to differences among families. The response to the challenge inoculation with G. clavigera was strong for some individual compounds, but primarily for monoterpenoids. Environment (site) also had a significant effect on the accumulation of some compounds, whereas for others, no significant environmental effect occurred. However, for a few compounds significant family x environment interactions were found. These results suggest that P. c. latifolia secondary chemistry is under strong genetic control, but the effects depend on the individual compounds and whether or not they are expressed constitutively or following induction.

  14. Timber, Browse, and Herbage on Selected Loblolly-Shortleaf Pine-Hardwood Forest Stands

    Science.gov (United States)

    Gale L. Wolters; Alton Martin; Warren P. Clary

    1977-01-01

    A thorough vegetation inventory was made on loblolly-shortleaf pine-hardwood stands scheduled by forest industry for clearcutting, site preparation, and planting to pine in north central Louisiana and southern Arkansas. Overstory timber, on the average, contained about equal proportions of softwood and hardwood basal area. Browse plants ranged from 5,500 to over 70,...

  15. Factors Influencing Formation of the Siberian Stone Pine Stands Near Settlements in Northern Taiga

    Directory of Open Access Journals (Sweden)

    V. N. Sedykh

    2014-04-01

    Full Text Available The peculiarities of formation of seed productive Siberian stone pine stands near settlements, due to the total destruction of the living ground cover and forest litter, providing heat influx in the root-inhabited zone of the Siberian stone pine trees is discussed in the paper.

  16. Impact of fire in two old-growth montane longleaf pine stands

    Science.gov (United States)

    John S. Kush; John C. Gilbert; Crystal Lupo; Na Zhou; Becky Barlow

    2013-01-01

    The structure of longleaf pine (Pinus palustris Mill.) forests of the Southeastern United States Coastal Plains has been the focus of numerous studies. By comparison, the forests in the mountains of Alabama and Georgia are not well understood. Less than 1 percent of longleaf pine stands found in the montane portion of longleaf’s range are considered...

  17. Estimating long-term carbon sequestration patterns in even- and uneven-aged southern pine stands

    Science.gov (United States)

    Don C. Bragg; James M. Guldin

    2010-01-01

    Carbon (C) sequestration has become an increasingly important consideration for forest management in North America, and has particular potential in pine-dominated forests of the southern United States. Using existing literature on plantations and long-term studies of naturally regenerated loblolly (Pinus taeda) and shortleaf (Pinus echinata) pine-dominated stands on...

  18. The push-pull tactic for mitigation of mountain pine beetle (Coleoptera: Curculionidae) damage in lodgepole and whitebark pines.

    Science.gov (United States)

    Gillette, Nancy E; Mehmel, Constance J; Mori, Sylvia R; Webster, Jeffrey N; Wood, David L; Erbilgin, Nadir; Owen, Donald R

    2012-12-01

    In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (Dendroctonus ponderosae Hopkins) in two studies. The first was conducted on replicated 4.04-ha plots in lodgepole pine stands (California, 2008) and the second on 0.81-ha plots in whitebark pine stands (Washington, 2010). In both studies, D. ponderosae population levels were moderate to severe. The treatments were 1) push-only (D. ponderosae antiaggregant semiochemicals alone); 2) push-pull (D. ponderosae antiaggregants plus perimeter traps placed at regular intervals, baited with four-component D. ponderosae aggregation pheromone); and 3) untreated controls. We installed monitoring traps baited with two-component D. ponderosae lures inside each plot to assess effect of treatments on beetle flight. In California, fewer beetles were collected in push-pull treated plots than in control plots, but push-only did not have a significant effect on trap catch. Both treatments significantly reduced the rate of mass and strip attacks by D. ponderosae, but the difference in attack rates between push-pull and push-only was not significant. In Washington, both push-pull and push-only treatments significantly reduced numbers of beetles caught in traps. Differences between attack rates in treated and control plots in Washington were not significant, but the push-only treatment reduced attack rates by 30% compared with both the control and push-pull treatment. We conclude that, at these spatial scales and beetle densities, push-only may be preferable for mitigating D. ponderosae attack because it is much less expensive, simpler, and adding trap-out does not appear to improve efficacy.

  19. "Growing trees backwards": Description of a stand reconstruction model

    Science.gov (United States)

    Jonathan D. Bakker; Andrew J. Sanchez Meador; Peter Z. Fule; David W. Huffman; Margaret M. Moore

    2008-01-01

    We describe an individual-tree model that uses contemporary measurements to "grow trees backward" and reconstruct past tree diameters and stand structure in ponderosa pine dominated stands of the Southwest. Model inputs are contemporary structural measurements of all snags, logs, stumps, and living trees, and radial growth measurements, if available. Key...

  20. Chemodiversity in terpene emissions at a boreal Scots pine stand

    Science.gov (United States)

    Bäck, J.; Aalto, J.; Henriksson, M.; Hakola, H.; He, Q.; Boy, M.

    2011-10-01

    Atmospheric chemistry in background areas is strongly influenced by natural vegetation. Coniferous forests are known to produce large quantities of volatile vapors, especially terpenes to the surrounding air. These compounds are reactive in the atmosphere, and contribute to the formation and growth of atmospheric new particles. Our aim was to analyze the variability of mono- and sesquiterpene emissions between Scots pine trees, in order to clarify the potential errors caused by using emission data obtained from only a few trees in atmospheric chemistry models. We also aimed at testing if stand history and seed origin has an influence on the chemotypic diversity. The inherited, chemotypic variability in mono- and sesquiterpene emission was studied in a seemingly homogeneous 47-yr-old stand in Southern Finland, where two areas differing in their stand regeneration history could be distinguished. Sampling was conducted in August 2009. Terpene concentrations in the air had been measured at the same site for seven years prior to branch sampling for chemotypes. Two main compounds, α-pinene and Δ3-carene formed together 40-97% of the monoterpene proportions in both the branch emissions and in the air concentrations. The data showed a bimodal distribution in emission composition, in particular in Δ3-carene emission within the studied population. 10% of the trees emitted mainly α-pinene and no Δ3-carene at all, whereas 20% of the trees where characterized as high Δ3-carene emitters (Δ3-carene forming >80% of total emitted monoterpene spectrum). An intermediate group of trees emitted equal amounts of both α-pinene and Δ3-carene. The emission pattern of trees at the area established using seeding as the artificial regeneration method differed from the naturally regenerated or planted trees, being mainly high Δ3-carene emitters. Some differences were also seen in e.g. camphene and limonene emissions between chemotypes, but sesquiterpene emissions did not differ

  1. Effects of salvage logging on fire risks after bark beetle outbreaks in Colorado lodgepole pine forests

    Science.gov (United States)

    Bryon J. Collins; Chuck C. Rhoades; Michael A. Battaglia; Robert M. Hubbard

    2012-01-01

    Most mature lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forests in the central and southern Rocky Mountains originated after stand-replacing wildfires or logging (Brown 1975, Lotan and Perry 1983, Romme 1982). In recent years, mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks have created a widespread, synchronous disturbance (i.e.,...

  2. Experience with the selection method in pine stands in the southern United States, with implications for future application

    Science.gov (United States)

    James M. Guldin

    2011-01-01

    The selection method applied in shade-intolerant pine stands in the southern United States has been shown to be an effective method of uneven-aged silviculture, but it is becoming less frequently practiced for a variety of reasons. Economically, the high value of standing timber puts fully stocked uneven-aged pine stands at risk of liquidation if the timberland is sold...

  3. A Comparison of Fire Intensity levels for stand replacement of table mountain pine (Pinus pungens Lamb.)

    Science.gov (United States)

    Thomas A. Waldrop; Patrick H. Brose

    1999-01-01

    Stand-replacement prescribed fire has been recommended to regenerate stands of table mountain pine (Pinus pungens Lamb.) in the Southern Appalachian Mountains because the species has serotinous cones and is shade intolerant. A 350 ha prescribed fire in northeast Georgia provided an opportunity to observe overstory mortality and regeneration of table...

  4. Silvicultural interpretation of natural vegetation dynamics in ageing Scots pine stands for their conversion into mixed broadleaved stands

    NARCIS (Netherlands)

    Kint, V.; Geudens, G.; Mohren, G.M.J.; Lust, N.

    2006-01-01

    In many West-European regions there is principal consensus on the conversion of homogeneous even-aged Scots pine plantations into mixed broadleaved stands. In recent years, interest is growing for conversion management in which managers try to maximise the use of natural processes by steering or

  5. Growing season soil moisture following restoration treatments of varying intensity in semi-arid ponderosa pine forests

    Science.gov (United States)

    O'Donnell, F. C.; Springer, A. E.; Sankey, T.; Masek Lopez, S.

    2014-12-01

    Forest restoration projects are being planned for large areas of overgrown semi-arid ponderosa pine forests of the Southwestern US. Restoration involves the thinning of smaller trees and prescribed or managed fire to reduce tree density, restore a more natural fire regime, and decrease the risk of catastrophic wildfire. The stated goals of these projects generally reduced plant water stress and improvements in hydrologic function. However, little is known about how to design restoration treatments to best meet these goals. As part of a larger project on snow cover, soil moisture, and groundwater recharge, we measured soil moisture, an indicator of plant water status, in four pairs of control and restored sites near Flagstaff, Arizona. The restoration strategies used at the sites range in both amount of open space created and degree of clustering of the remaining trees. We measured soil moisture using 30 cm vertical time domain reflectometry probes installed on 100 m transects at 5 m intervals so it would be possible to analyze the spatial pattern of soil moisture. Soil moisture was higher and more spatially variable in the restored sites than the control sites with differences in spatial pattern among the restoration types. Soil moisture monitoring will continue until the first snow fall, at which point measurements of snow depth and snow water equivalent will be made at the same locations.

  6. Acute and long-term effects of irradiation on pine (Pinus silvestris) stands post-Chernobyl

    International Nuclear Information System (INIS)

    Arkhipov, N.P.; Kuchma, N.D.; Askbrant, S.; Pasternak, P.S.; Musica, V.V.

    1994-01-01

    The effect of ionizing irradiation on the viability of pine stands after the fallout from the damaged nuclear energy plant at Chernobyl (ChNPP) was shown within the territory of the 10-km zone. During the period 1986-1991, irradiated and damaged forest stands, so-called 'red forest', located in this area were systematically classified by observation. Mortality rate, re-establishment, development of tree canopies, reproduction anomalies and stand viability were shown to be dependent on absorbed irradiation dose, on the age of the stand and on forest composition. For pine stands in the acutely affected zone, doses of more than 60 Gy resulted in a massive mortality and no regeneration of pine trees since 1987. The injured trees had burned or had dried-up. The drying process was accelerated by a massive production of pathogenic insects invading the dying trees. Specifically, irradiation doses of 10-60 Gy, 1-10 Gy and 0.1-1 Gy caused high, medium and low injury to the forest stands, respectively. Doses of less than 0.1 Gy did not cause any visible damage to the trees. In 1987, repair processes were displayed by the tree canopies and practically the entire viability of the forest stands had recovered except for trees in the acute and highly affected zones. The young forest was reestablished in the same place as the perished trees and new pine saplings were planted on the reclaimed areas

  7. Acute and long-term effects of irradiation on pine (Pinus silvestris) stands post-Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Arkhipov, N.P.; Kuchma, N.D. (Department of Radiology and Land Restoration, Pripyat Research and Industrial Association, Chernobyl (Ukraine)); Askbrant, S. (National Radiation Protection Institute, Stockholm (Sweden)); Pasternak, P.S.; Musica, V.V. (Lyes Research and Industrial Association, Kharykov (Ukraine))

    1994-10-14

    The effect of ionizing irradiation on the viability of pine stands after the fallout from the damaged nuclear energy plant at Chernobyl (ChNPP) was shown within the territory of the 10-km zone. During the period 1986-1991, irradiated and damaged forest stands, so-called 'red forest', located in this area were systematically classified by observation. Mortality rate, re-establishment, development of tree canopies, reproduction anomalies and stand viability were shown to be dependent on absorbed irradiation dose, on the age of the stand and on forest composition. For pine stands in the acutely affected zone, doses of more than 60 Gy resulted in a massive mortality and no regeneration of pine trees since 1987. The injured trees had burned or had dried-up. The drying process was accelerated by a massive production of pathogenic insects invading the dying trees. Specifically, irradiation doses of 10-60 Gy, 1-10 Gy and 0.1-1 Gy caused high, medium and low injury to the forest stands, respectively. Doses of less than 0.1 Gy did not cause any visible damage to the trees. In 1987, repair processes were displayed by the tree canopies and practically the entire viability of the forest stands had recovered except for trees in the acute and highly affected zones. The young forest was reestablished in the same place as the perished trees and new pine saplings were planted on the reclaimed areas.

  8. Development of merchantable volume equations for natural brutian pine and black pine stands in Eğirdir District

    Directory of Open Access Journals (Sweden)

    Ramazan Özçelik

    2016-01-01

    Full Text Available Determination of stem standing volume is very useful for both sustainable management of timber resources and practical purposes in forestry. Brutian pine (Pinus brutia Ten. and black pine (Pinus nigra Arnold. are important raw material of forest products industry of Turkey. With ever changing market conditions, there is a need to accurately estimate tree volumes utilizing multiple upper stem merchantability limits. This is not currently possible with the existing total stem volume tables for these three species. Nowadays, taper equations are the best way to estimate volume for saw timber and biomass purposes. In this study, variable exponent taper equations evaluated and fitted to data come from 253 destructively sampled trees which were collected in natural brutian pine and black pine stands in Eğirdir district. For this aim, the taper equations of Lee et al. (2003, Kozak (2004, and Sharma and Zhang (2004 were used. A second-order continuous-time autoregressive error structure was used to correct the inherent autocorrelation in the hierarchical data. The proposed models generally performed better for Merchantable tree volume. Results show that the Kozak (2004 taper equation was superior to the other equations in predicting diameter and merchantable height, while The Sharma and Zhang (2004 taper model provided the best predictions for merchantable volume than the other models. The one of the important results of this study, the importance of checking fit statistics of taper equations for both diameters and volume estimations.As a results, Sharma and Zhang (2004 taper model recommended for estimating diameter at a specific height, height to a specific diameter along the stem, and merchantable volume for brutian pine and black pine stands in Eğirdir analyzed

  9. Naturally seeded versus planted ponderosa pine seedlings in group-selection openings

    Science.gov (United States)

    Philip M. McDonald; Gary Fiddler; Martin Ritchie; Paula Anderson

    2009-01-01

    The purpose of this article was to determine whether natural regeneration or planted seedlings should be used in group-selection openings. The answer dependson the survival and growth rate of both types of seedlings, and that could depend on the size of the openings and the effect of trees on their edge. In thisside-by-side study, the natural pine seedlings originated...

  10. Does overshoot in leaf development of ponderosa pine in wet years leads to bark beetle outbreaks on fine-textured soils in drier years?

    Directory of Open Access Journals (Sweden)

    Wendy Peterman

    2014-12-01

    Full Text Available Background Frequent outbreaks of insects and diseases have been recorded in the native forests of western North America during the last few decades, but the distribution of these outbreaks has been far from uniform. In some cases, recent climatic variations may explain some of this spatial variation along with the presence of expansive forests composed of dense, older trees. Forest managers and policy makers would benefit if areas especially prone to disturbance could be recognized so that mitigating actions could be taken. Methods We use two ponderosa pine-dominated sites in western Montana, U.S.A. to apply a modeling approach that couples information acquired via remote sensing, soil surveys, and local weather stations to assess where bark beetle outbreaks might first occur and why. Although there was a general downward trend in precipitation for both sites over the period between 1998 and 2010 (slope = −1.3, R2 = 0.08, interannual variability was high. Some years showed large increases followed by sharp decreases. Both sites had similar topography and fire histories, but bark beetle activity occurred earlier (circa 2000 to 2001 and more severely on one site than on the other. The initial canopy density of the two sites was also similar, with leaf area indices ranging between 1.7-2.0 m2·m−2. We wondered if the difference in bark beetle activity was related to soils that were higher in clay content at site I than at site II. To assess this possibility, we applied a process-based stand growth model (3-PG to analyze the data and evaluate the hypotheses. Results We found that when wet years were followed by drier years, the simulated annual wood production per unit of leaf area, a measure of tree vigor, dropped below a critical threshold on site I but not on site II. Conclusion We concluded that the difference in vulnerability of the two stands to beetle outbreaks can be explained largely by differences in gross photosynthesis

  11. Multiple diseases impact survival of pine species planted in red spine stands harvested in spatially variable retention patterns

    Science.gov (United States)

    M.E. Ostry; M.J. Moore; C.C. Kern; R.C. Venette; B.J. Palik

    2012-01-01

    Increasing the diversity of species and structure of red pine (Pinus resinosa) is often a management goal in stands simplified by practices such as fire suppression and plantation management in many areas of the Great Lakes Region. One approach to diversification is to convert predominantly even-aged, pure red pine stands to multi-cohort, mixed-...

  12. Long-Term Prescribed Burning Regime Has Little Effect on Springtails in Pine Stands of Southern Arkansas

    Science.gov (United States)

    Michele L. Renschin; Lynne C. Thompson; Michael G. Shelton

    2004-01-01

    Concerns regarding the impacts of prescribed fires on faunal communities in pine stands have led to numerous studies. One soil/litter insect that may be influenced by fire is springtails, an important member of the forest floor community. A study was conducted in burned and unburned loblolly/shortleaf pine stands in southeastern Arkansas to examine whether springtail...

  13. "Growing trees backwards": Description of a stand reconstruction model (P-53)

    Science.gov (United States)

    Jonathan D. Bakker; Andrew J. Sanchez Meador; Peter Z. Fule; David W. Huffman; Margaret M. Moore

    2008-01-01

    We describe an individual-tree model that uses contemporary measurements to "grow trees backward" and reconstruct past tree diameters and stand structure in ponderosa pine dominated stands of the Southwest. Model inputs are contemporary structural measurements of all snags, logs, stumps, and living trees, and radial growth measurements, if available. Key...

  14. Fire in longleaf pine stand management: an economic analysis

    Science.gov (United States)

    Rodney L. Busby; Donald G. Hodges

    1999-01-01

    A simulation analysis of the economics of using prescribed fire as a forest management tool in the management of longleaf pine (Pinus palustris Mill.) plantations was conducted. A management regime using frequent prescribed fire was compared to management regimes involving fertilization and chemical release, chemical control, and mechanical control. Determining the...

  15. Periodic Burning In Table Mountain-Pitch Pine Stands

    Science.gov (United States)

    Russell B. Randles; David H. van Lear; Thomas A. Waldrop; Dean M. Simon

    2002-01-01

    Abstract - The effects of multiple, low intensity burns on vegetation and wildlife habitat in Table Mountain (Pinus pungens Lamb.)-pitch (Pinus rigida Mill.) pine communities were studied in the Blue Ridge Mountains of North Carolina. Treatments consisted of areas burned from one to four times at 3-4 year...

  16. Development of a Regional Lidar-Derived Above-Ground Biomass Model with Bayesian Model Averaging for Use in Ponderosa Pine and Mixed Conifer Forests in Arizona and New Mexico, USA

    Directory of Open Access Journals (Sweden)

    Karis Tenneson

    2018-03-01

    Full Text Available Historical forest management practices in the southwestern US have left forests prone to high-severity, stand-replacement fires. Reducing the cost of forest-fire management and reintroducing fire to the landscape without negative impact depends on detailed knowledge of stand composition, in particular, above-ground biomass (AGB. Lidar-based modeling techniques provide opportunities to increase ability of managers to monitor AGB and other forest metrics at reduced cost. We developed a regional lidar-based statistical model to estimate AGB for Ponderosa pine and mixed conifer forest systems of the southwestern USA, using previously collected field data. Model selection was performed using Bayesian model averaging (BMA to reduce researcher bias, fully explore the model space, and avoid overfitting. The selected model includes measures of canopy height, canopy density, and height distribution. The model selected with BMA explains 71% of the variability in field-estimates of AGB, and the RMSE of the two independent validation data sets are 23.25 and 32.82 Mg/ha. The regional model is structured in accordance with previously described local models, and performs equivalently to these smaller scale models. We have demonstrated the effectiveness of lidar for developing cost-effective, robust regional AGB models for monitoring and planning adaptively at the landscape scale.

  17. Respiratory potential in sapwood of old versus young ponderosa pine trees in the Pacific Northwest.

    Science.gov (United States)

    Pruyn, Michele L; Gartner, Barbara L; Harmon, Mark E

    2002-02-01

    Our primary objective was to present and test a new technique for in vitro estimation of respiration of cores taken from old trees to determine respiratory trends in sapwood. Our secondary objective was to quantify effects of tree age and stem position on respiratory potential (rate of CO2 production of woody tissue under standardized laboratory conditions). We extracted cores from one to four vertical positions in boles of +200-, +50- and +15-year-old Pinus ponderosa Dougl. ex Laws. trees. Cores were divided into five segments corresponding to radial depths of inner bark; outer, middle and inner sapwood; and heartwood. Data suggested that core segment CO2 production was an indicator of its respiratory activity, and that potential artifacts caused by wounding and extraction were minimal. On a dry mass basis, respiratory potential of inner bark was 3-15 times greater than that of sapwood at all heights for all ages (P sapwood at all heights and in all ages of trees, outer sapwood had a 30-60% higher respiratory potential than middle or inner sapwood (P sapwood. For all ages of trees, sapwood rings produced in the same calendar year released over 50% more CO2 at treetops than at bases (P sapwood volume basis, sapwood of younger trees had higher respiratory potential than sapwood of older trees. In contrast, the trend was reversed when using the outer-bark surface area of stems as a basis for comparing respiratory potential. The differences observed in respiratory potential calculated on a core dry mass, sapwood volume, or outer-bark surface area basis clearly demonstrate that the resulting trends within and among trees are determined by the way in which the data are expressed. Although these data are based on core segments rather than in vivo measurements, we conclude that the relative differences are probably valid even if the absolute differences are not.

  18. Observations and models of emissions of volatile terpenoid compounds from needles of ponderosa pine trees growing in situ: control by light, temperature and stomatal conductance.

    Science.gov (United States)

    Harley, Peter; Eller, Allyson; Guenther, Alex; Monson, Russell K

    2014-09-01

    Terpenoid emissions from ponderosa pine (Pinus ponderosa subsp. scopulorum) were measured in Colorado, USA over two growing seasons to evaluate the role of incident light, needle temperature, and stomatal conductance in controlling emissions of 2-methyl-3-buten-2-ol (MBO) and several monoterpenes. MBO was the dominant daylight terpenoid emission, comprising on average 87% of the total flux, and diurnal variations were largely determined by light and temperature. During daytime, oxygenated monoterpenes (especially linalool) comprised up to 75% of the total monoterpenoid flux from needles. A significant fraction of monoterpenoid emissions was dependent on light and 13CO2 labeling studies confirmed de novo production. Thus, modeling of monoterpenoid emissions required a hybrid model in which a significant fraction of emissions was dependent on both light and temperature, while the remainder was dependent on temperature alone. Experiments in which stomata were forced to close using abscisic acid demonstrated that MBO and a large fraction of the monoterpene flux, presumably linalool, could be limited at the scale of seconds to minutes by stomatal conductance. Using a previously published model of terpenoid emissions, which explicitly accounts for the physicochemical properties of emitted compounds, we were able to simulate these observed stomatal effects, whether induced experimentally or arising under naturally fluctuation conditions of temperature and light. This study shows unequivocally that, under naturally occurring field conditions, de novo light-dependent monoterpenes comprise a significant fraction of emissions in ponderosa pine. Differences between the monoterpene composition of ambient air and needle emissions imply a significant non-needle emission source enriched in Δ-3-carene.

  19. A Survival Model for Shortleaf Pine Tress Growing in Uneven-Aged Stands

    Science.gov (United States)

    Thomas B. Lynch; Lawrence R. Gering; Michael M. Huebschmann; Paul A. Murphy

    1999-01-01

    A survival model for shortleaf pine (Pinus echinata Mill.) trees growing in uneven-aged stands was developed using data from permanently established plots maintained by an industrial forestry company in western Arkansas. Parameters were fitted to a logistic regression model with a Bernoulli dependent variable in which "0" represented...

  20. Shortleaf pine seed production in natural stands in the Ouachita and Ozark mountains

    Science.gov (United States)

    Michael G. Shelton; Robert F. Wittwer

    1996-01-01

    Seed production of shortleaf pine (Pinus echinata Mill.) was monitored from 1965 to 1974 to determine the periodicity qf seed crops in both woods-run stands and seed-production areas. One bumper and two good seed crops occurred during the 9-yr period. The two largest crops occurred in successive years, then seed production was low for 4 yr before...

  1. Spatial analysis of longleaf pine stand dynamics after 60 years of management

    Science.gov (United States)

    John C. Gilbert; John S. Kush; Rebecca J. Barlow

    2012-01-01

    There are still many questions and misconceptions about the stand dynamics of naturally-regenerated longleaf pine (Pinus palustris Mill.). Since 1948, the “Farm Forty,” a forty-acre tract located on the USDA Forest Service Escambia Experimental Forest near Brewton, Alabama, has been managed to create high quality wood products, to successfully...

  2. Relationship of Aboveground Biomass Production Site Index and Soil Characteristics in a Loblolly Pine Stand

    Science.gov (United States)

    Minyi Zhou; Thomas J. Dean

    2004-01-01

    As a part of the continuing studies of the Cooperative Research in Sustainable Silviculture and Soil Productivity (CRiSSSP), 24 experimental plots in a loblolly pine (Pinus taeda L.) stand have recently been installed near Natchitoches, LA. The plots were uniformly assigned to 3 blocks based on topography (i.e., up slope, midslope, and down slope)....

  3. Age structure of a southern pine stand following 72 years of uneven-aged silviculture

    Science.gov (United States)

    Don C. Bragg

    2012-01-01

    Work on uneven-aged silviculture in southern pine stands on the Crossett Experimental Forest (CEF) began in the 1930s, when a number of 16.2-ha compartments were placed into a series of demonstration projects and studies (Reynolds 1980). Two of these compartments, the Good and Poor Farm Forestry Forties, have been maintained continuously in this silvicultural regime...

  4. Seasonal photosynthesis and water relations of juvenile loblolly pine relative to stand density and canopy position

    Science.gov (United States)

    Zhenmin Tang; Jim L. Chambers; Mary A. Sword Sayer; James P. Barnett

    2003-01-01

    To assess the effects of stand density and canopy environment on tree physiology, we measured gas exchange responses of the same needle age class of 16-year-old loblolly pines (Pinus taeda L.) in thinned (512 trees ha-1) and non-thinned treatment plots (2,863 trees ha-1) in central Louisiana....

  5. Estimating air drying times of small-diameter ponderosa pine and Douglas-fir logs.

    Science.gov (United States)

    William T. Simpson; Xiping. Wang

    2003-01-01

    Because dense stands of softwood trees are causing forest health problems in the western United States, new ways to use this material need to be found. One option is to use this material as logs rather than sawing it into lumber. For many applications, logs require some degree of drying. Even though these logs may be considered small diameter, they are large compared...

  6. Effect of season and interval of prescribed burn on ponderosa pine butterfly defoliation patterns

    Science.gov (United States)

    Becky K. Kerns; Douglas J. Westlind

    2013-01-01

    Current knowledge concerning the interactions between forest disturbances such as fire and insect defoliation is limited. Wildfires and prescribed burns may influence the intensity and severity of insect outbreaks by affecting the vigor of residual trees, altering aspects of stand structure and abundance of preferred hosts, and by changing the physical environment...

  7. Logging costs and cutting methods in young-growth ponderosa pine in California

    Science.gov (United States)

    Philip M. McDonald; William A. Atkinson; Dale O. Hall

    1969-01-01

    Mixed-conifer stands at the Challenge Experimental Forest, Calif., were cut to four specifications: seed-tree, group selection, single tree selection, and clearcut. Logging costs and production rates were compared and evaluated. Cutting method had little effect on felling or skidding production; felling ranged from 1,802 to 2,019 bd ft per hour, and skidding from 3,138...

  8. Effects of CO(sub 2) and nitrogen fertilization on soils planted with ponderosa pine; FINAL

    International Nuclear Information System (INIS)

    Johnson, D.W.

    1996-01-01

    The effects of elevated CO(sub 2) (ambient, 525, and 700(micro)l l(sup -1))and N fertilization (0, 10, and 20 g N m(sup 2) yr(sup -1)) on soil pCO(sub 2), CO(sub 2) efflux, soil solution chemistry, and soil C and nutrients in an open-top chamber study with Pinus ponderosa are described. Soil pCO(sub 2) and CO(sub 2) efflux were significantly greater with elevated CO(sub 2), at first (second growing season) in the 525(micro)l l(sup -1) and later (fourth and fifth growing seasons) in the 700(micro)l l(sup -1) CO(sub 2) treatments. Soil solution HCO(sub 3)(sup -) concentrations were temporarily elevated in the 525(micro)l l(sup -1) CO(sub 2) treatment during the second growing season, consistent with the elevated pCO(sub 2). Nitrogen fertilization had no consistent effect on soil pCO(sub 2) or CO(sub 2) efflux, but did have the expected negative effect on exchangeable Ca(sup 2+), K(sup+), and Mg(sup 2+), presumed to be caused by increased nitrate leaching. Elevated CO(sub 2) had no consistent effects on exchangeable Ca(sup 2+), K(sup+), and Mg(sup 2+), but did cause temporary reductions in soil NO(sup 3(sup -)) (second growing season). Statistically significant negative effects of elevated CO(sub 2) on soil extractable P were noted in the third and sixth growing seasons. However, these patterns in extractable P reflected pre-treatment differences, which, while not statistically significant, followed the same pattern. Statistically significant effects of elevated CO(sub 2) on total C and N in soils were noted in the third and sixth growing seasons, but these effects were inconsistent among N treatments and years. The clearest effect of elevated CO(sub 2) was in the case of C/N ratio in year 6, where there was a consistent, positive effect. The increases in C/N ratio with elevated CO(sub 2) in year six were largely a result of reductions in soil N rather than increases in soil C. Future papers will assess whether this apparent reduction in soil N could have been

  9. Southern pine beetle infestations in relation to forest stand conditions, previous thinning, and prescribed burning: evaluation of the Southern Pine Beetle Prevention Program

    Science.gov (United States)

    John T. Nowak; James R. Meeker; David R. Coyle; Chris A. Steiner; Cavell Brownie

    2015-01-01

    Since 2003, the Southern Pine Beetle Prevention Program (SPBPP) (a joint effort of the USDA Forest Service and Southern Group of State Foresters) has encouraged and provided cost-share assistance for silvicultural treatments to reduce stand/forest susceptibility to the southern pine beetle (SPB)(Dendroctonus frontalis Zimmermann) in the southeastern United States....

  10. Biome-BGC: Modeling Carbon Dynamics in Ponderosa Pine Stands (Law et al. 2003)

    Data.gov (United States)

    National Aeronautics and Space Administration — This archived model product contains the directions, executables, and procedures for running Biome-BGC, Version 4.1.2, to recreate the results of the following...

  11. Spatial and temporal corroboration of a fire-scar-based fire history in a frequently burned ponderosa pine forest.

    Science.gov (United States)

    Farris, Calvin A; Baisan, Christopher H; Falk, Donald A; Yool, Stephen R; Swetnam, Thomas W

    2010-09-01

    Fire scars are used widely to reconstruct historical fire regime parameters in forests around the world. Because fire scars provide incomplete records of past fire occurrence at discrete points in space, inferences must be made to reconstruct fire frequency and extent across landscapes using spatial networks of fire-scar samples. Assessing the relative accuracy of fire-scar fire history reconstructions has been hampered due to a lack of empirical comparisons with independent fire history data sources. We carried out such a comparison in a 2780-ha ponderosa pine forest on Mica Mountain in southern Arizona (USA) for the time period 1937-2000. Using documentary records of fire perimeter maps and ignition locations, we compared reconstructions of key spatial and temporal fire regime parameters developed from documentary fire maps and independently collected fire-scar data (n = 60 plots). We found that fire-scar data provided spatially representative and complete inventories of all major fire years (> 100 ha) in the study area but failed to detect most small fires. There was a strong linear relationship between the percentage of samples recording fire scars in a given year (i.e., fire-scar synchrony) and total area burned for that year (y = 0.0003x + 0.0087, r2 = 0.96). There was also strong spatial coherence between cumulative fire frequency maps interpolated from fire-scar data and ground-mapped fire perimeters. Widely reported fire frequency summary statistics varied little between fire history data sets: fire-scar natural fire rotations (NFR) differed by or = 25% of study area burned) were identical between data sets (25.5 yr); fire-scar MFIs for all fire years differed by 1.2 yr from documentary records. The known seasonal timing of past fires based on documentary records was furthermore reconstructed accurately by observing intra-annual ring position of fire scars and using knowledge of tree-ring growth phenology in the Southwest. Our results demonstrate clearly

  12. Forest structure and plant diversity in maritime pine (Pinus pinaster Ait.) stands in central Spain

    Energy Technology Data Exchange (ETDEWEB)

    Osorio, L. F.; Bravo, F.; Zaldivar, P.; Pando, V.

    2009-07-01

    The relationship between forest structure and plant diversity in Mediterranean Maritime pine stands (Pinus pinaster Ait.) in the Iberian Range (Spain) was studied. Forty eight stands were sampled. In each, a circular plot (15 m radius) and a transect (25*1 m{sup 2}) were established to estimate stand variables and record presence and abundance of vascular species respectively. Canonical correlation analysis (CCA), simple correlations and multiple stepwise linear regressions were used to explore the relationship between plant diversity and forest structure. Correlation between diversity measurements and stand variables is very weak, but significant correlations were found when evaluating each set of variables separately. Presence and cover of some species (for instance, Veronica arvensis L. or Micropyrum tenellum (L.) Link) is correlated with stand variables; however, determination coefficients found in step-by-step regression are not significant. (Author) 34 refs.

  13. The frequency of forest fires in Scots pine stands of Tuva, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Ivanova, G A; Kukavskaya, E A [Russian Academy of Sciences, Siberian Branch, V N Sukachev Institute of Forest, Akademgorodok, Krasnoyarsk, 660036 (Russian Federation); Ivanov, V A [Siberian State Technological University, Krasnoyarsk, 660049 (Russian Federation); Soja, A J, E-mail: GAIvanova@ksc.krasn.r [National Institute of Aerospace, Resident at NASA Langley Research Center, MS 420, Hampton, VA 23681-2199 (United States)

    2010-01-15

    Forest fires resulting from long periods of drought cause extensive forest ecosystem destruction and can impact on the carbon balance and air quality and feed back to the climate system, regionally and globally. Past fire frequency is reconstructed for Tuvan Scots pine stands using dendrochronology and statistics. Central Tuvan Scots pine (Pinus sylvestris) stands are subject to annual fire regimes; however high intensity fires are rare but they are responsible for most of the damage. Low, medium, and high severity fires have shaped the multi-story Scots pine communities, locally and regionally. Fire type and frequency are directly related to weather and climate and are also dependent on anthropogenic influences. The primary dry period, which promotes fire ignition and spread, in Tuva occurs in April and May. In some years, the precipitation deficit combined with high air temperatures induces long periods of drought. Unlike the typical surface fire regime, forest fires that burn during these extreme droughts often become crown fires that result in substantial forest damage and carbon release. The mean fire interval (MFI) is found to be 10.4 years in Balgazyn stands, and the landscape-scale MFI is 22.4 years. High severity, stand-replacing crown fires have a longer MFI. The warmer and dryer weather that is predicted by global climate models is evident in Tuva, and we believe that these changes in weather and climate have resulted in increased fire intensity and severity, rather than fire frequency in the Tuvan region.

  14. The frequency of forest fires in Scots pine stands of Tuva, Russia

    International Nuclear Information System (INIS)

    Ivanova, G A; Kukavskaya, E A; Ivanov, V A; Soja, A J

    2010-01-01

    Forest fires resulting from long periods of drought cause extensive forest ecosystem destruction and can impact on the carbon balance and air quality and feed back to the climate system, regionally and globally. Past fire frequency is reconstructed for Tuvan Scots pine stands using dendrochronology and statistics. Central Tuvan Scots pine (Pinus sylvestris) stands are subject to annual fire regimes; however high intensity fires are rare but they are responsible for most of the damage. Low, medium, and high severity fires have shaped the multi-story Scots pine communities, locally and regionally. Fire type and frequency are directly related to weather and climate and are also dependent on anthropogenic influences. The primary dry period, which promotes fire ignition and spread, in Tuva occurs in April and May. In some years, the precipitation deficit combined with high air temperatures induces long periods of drought. Unlike the typical surface fire regime, forest fires that burn during these extreme droughts often become crown fires that result in substantial forest damage and carbon release. The mean fire interval (MFI) is found to be 10.4 years in Balgazyn stands, and the landscape-scale MFI is 22.4 years. High severity, stand-replacing crown fires have a longer MFI. The warmer and dryer weather that is predicted by global climate models is evident in Tuva, and we believe that these changes in weather and climate have resulted in increased fire intensity and severity, rather than fire frequency in the Tuvan region.

  15. Water and Energy Balances of Loblolly Pine Plantation Forests during a Full Stand Rotation

    Science.gov (United States)

    Sun, G.; Mitra, B.; Domec, J. C.; Gavazi, M.; Yang, Y.; Tian, S.; Zietlow, D.; McNulty, S.; King, J.; Noormets, A.

    2017-12-01

    Loblolly pine (Pinus taeda) plantations in the southern U.S. are well recognized for their ecosystem services in supplying clean and stable water and mitigating climate change through carbon sequestration and solar energy partitioning. Since 2004, we have monitored energy, water, and carbon fluxes in a chronosequence of three drained loblolly pine plantations using integrated methods that include eddy covariance, sap flux, watershed hydrometeorology, remote sensing, and process-based simulation modeling. Study sites were located on the eastern North Carolina coastal plain, representing highly productive ecosystems with high groundwater table, and designated in the Ameriflux network as NC1 (0-10 year old), NC2 (12-25 year old) and NC3 (0-3 years old). The 13-year study spanned a wide range of annual precipitation (900-1600 mm/yr) including two exceptionally dry years during 2007-2008. We found that the mature stand (NC2) had higher net radiation (Rn) flux due to its lower albedo (α =0.11-12), compared with the young stands (NC1, NC3) (α=0.15-0.18). Annually about 75%-80% of net radiation was converted to latent heat in the pine plantations. In general, the mature stand had higher latent heat flux (LE) (i.e. evapotranspiration (ET)) rates than the young stands, but ET rates were similar during wet years when the groundwater table was at or near the soil surface. During a historic drought period (i.e., 2007-2008), total stand annual ET exceeded precipitation, but decreased about 30% at NC2 when compared to a normal year (e.g., 2006). Field measurements and remote sensing-based modeling suggested that annual ET rates increased linearly from planting age (about 800 mm) to age 15 (about 1050 mm) and then stabilized as stand leaf area index leveled-off. Over a full stand rotation, approximately 70% (young stand) to 90% (mature stand) of precipitation was returned to the atmosphere through ET. We conclude that both climatic variability and canopy structure controlled the

  16. Repeated Stand-Replacing Crown Fires Affect Seed Morphology and Germination in Aleppo pine

    Directory of Open Access Journals (Sweden)

    Antonio Saracino

    2017-06-01

    Full Text Available Post-fire reproductive niche of Aleppo pine (Pinus halepensis is deeply interlaced with fire products. Indeed, the high pH and low osmotic potentials of ash beds under burnt crowns constitute the main constraints to seed germination. In this study, we aim to investigate whether fire recurrence, through the physico-chemical constraints imposed by the ash beds, affects the reproduction ability of P. halepensis at the germination stage. To this aim, Aleppo pine seeds were collected in neighboring even-aged stands subjected to 0, 1, or 2 fires (namely fire cohorts, and seed morphology and germination performance, in terms of cumulative germination and germination kinetics, were studied under increasing osmotic potentials (from 0.0 to −1.2 MPa and pH (from 6 to 11. Besides fire history, the role of ontogenetic age of mother plants on seed morphology and germination was also investigated. Differences in seed morphology among the three cohorts have been highlighted in a multivariate context, with anisotropic enlargement of the seeds produced by pine stands experiencing repeated fires. The patterns of seed germination varied primarily in relation to the fire cohort, with seeds from the pine stand experiencing repeated fires exhibiting enhanced tolerance to pH stress. Conversely, germination performances under osmotic constraints mainly depends on tree ontogenetic stage, with an involvement of fire history especially in the timing of seed germination. Our results suggest that, at least in the short term, fire recurrence does not constrain the reproduction ability of Aleppo pine. These results highlight the need for further research to elucidate the mechanisms behind these responses to recurrent fires.

  17. Repeated Stand-Replacing Crown Fires Affect Seed Morphology and Germination in Aleppo pine

    Science.gov (United States)

    Saracino, Antonio; Bellino, Alessandro; Allevato, Emilia; Mingo, Antonio; Conti, Stefano; Rossi, Sergio; Bonanomi, Giuliano; Carputo, Domenico; Mazzoleni, Stefano

    2017-01-01

    Post-fire reproductive niche of Aleppo pine (Pinus halepensis) is deeply interlaced with fire products. Indeed, the high pH and low osmotic potentials of ash beds under burnt crowns constitute the main constraints to seed germination. In this study, we aim to investigate whether fire recurrence, through the physico-chemical constraints imposed by the ash beds, affects the reproduction ability of P. halepensis at the germination stage. To this aim, Aleppo pine seeds were collected in neighboring even-aged stands subjected to 0, 1, or 2 fires (namely fire cohorts), and seed morphology and germination performance, in terms of cumulative germination and germination kinetics, were studied under increasing osmotic potentials (from 0.0 to −1.2 MPa) and pH (from 6 to 11). Besides fire history, the role of ontogenetic age of mother plants on seed morphology and germination was also investigated. Differences in seed morphology among the three cohorts have been highlighted in a multivariate context, with anisotropic enlargement of the seeds produced by pine stands experiencing repeated fires. The patterns of seed germination varied primarily in relation to the fire cohort, with seeds from the pine stand experiencing repeated fires exhibiting enhanced tolerance to pH stress. Conversely, germination performances under osmotic constraints mainly depends on tree ontogenetic stage, with an involvement of fire history especially in the timing of seed germination. Our results suggest that, at least in the short term, fire recurrence does not constrain the reproduction ability of Aleppo pine. These results highlight the need for further research to elucidate the mechanisms behind these responses to recurrent fires. PMID:28713415

  18. Responses of Ips pini (Say), Pityogenes knechteli Swaine and Associated Beetles (Coleoptera) to Host Monoterpenes in Stands of Lodgepole Pine

    Science.gov (United States)

    Daniel R. Miller; John H. Borden

    2003-01-01

    We conducted seven experiments in stands of mature lodgepole pine in southern British Columbia to elucidate the role of host volatiles in the semiochemical ecology of the pine engraver, Ips pini (Say) (Coleoptera: Scolytidae), with particular reference to the behavioral responses of predators and competing species of bark beetles. Our results demonstrated that the...

  19. Reproducing pine stands on the eastern shore of Maryland using a seed-tree cutting and preparing seedbeds with machinery and summer fires

    Science.gov (United States)

    S. Little; J. J. Mohr

    1954-01-01

    Pure pine stands are the most profitable forest crop on upland sites of the Eastern Shore of Maryland. The stands have been common in the past, because loblolly pine and pond pine usually made up most of the first forest growth on abandoned farmland. And apparently nearly all upland sites have been tilled at one time or another.

  20. Influence of thinning intensity and canopy type on Scots pine stand and growth dynamics in a mixed managed forest

    Energy Technology Data Exchange (ETDEWEB)

    Primicia, I.; Artázcoz, R.; Imbert, J.B.; Puertas, F.; Traver, M.C.; Castillo, F.J.

    2016-07-01

    Aim of the study: We analysed the effects of thinning intensity and canopy type on Scots pine growth and stand dynamics in a mixed Scots pine-beech forest. Area of the study: Western Pyrenees. Material and methods: Three thinning intensities were applied in 1999 (0, 20 and 30% basal area removed) and 2009 (0, 20 and 40%) on 9 plots. Within each plot, pure pine and mixed pine-beech patches are distinguished. All pine trees were inventoried in 1999, 2009 and 2014. The effects of treatments on the tree and stand structure variables (density, basal area, stand and tree volume), on the periodic annual increment in basal area and stand and tree volume, and on mortality rates, were analysed using linear mixed effects models. Main Results: The enhancement of tree growth was mainly noticeable after the second thinning. Growth rates following thinning were similar or higher in the moderate than in the severe thinning. Periodic stand volume annual increments were higher in the thinned than in the unthinned plots, but no differences were observed between the thinned treatments. We observed an increase in the differences of the Tree volume annual increment between canopy types (mixed < pure) over time in the unthinned plots, as beech crowns developed. Research highlights: Moderate thinning is suggested as an appropriate forest practice at early pine age in these mixed forests, since it produced higher tree growth rates than the severe thinning and it counteracted the negative effect of beech on pine growth observed in the unthinned plots. (Author)

  1. Interception loss, throughfall and stemflow in a maritime pine stand. I. Variability of throughfall and stemflow beneath the pine canopy

    Science.gov (United States)

    Loustau, D.; Berbigier, P.; Granier, A.; Moussa, F. El Hadj

    1992-10-01

    Patterns of spatial variability of throughfall and stemflow were determined in a maritime pine ( Pinus pinaster Ait.) stand for two consecutive years. Data were obtained from 52 fixed rain gauges and 12 stemflow measuring devices located in a 50m × 50m plot at the centre of an 18-year-old stand. The pine trees had been sown in rows 4m apart and had reached an average height of 12.6m. The spatial distribution of stems had a negligible effect on the throughfall partitioning beneath the canopy. Variograms of throughfall computed for a sample of storms did not reveal any spatial autocorrelation of throughfall for the sampling design used. Differences in throughfall, in relation to the distance from the rows, were not consistently significant. In addition, the distance from the tree stem did not influence the amount of throughfall. The confidence interval on the amount of throughfall per storm was between 3 and 8%. The stemflow was highly variable between trees. The effect of individual trees on stemflow was significant but the amount of stemflow per tree was not related to tree size (i.e. height, trunk diameter, etc.). The cumulative sampling errors on stemflow and throughfall for a single storm created a confidence interval of between ±7 and ±51% on interception. This resulted mainly from the low interception rate and sampling error on throughfall.

  2. Vegetation diversity of the Scots pine stands in different forest sites in the Turawa Forest District

    OpenAIRE

    Stefańska-Krzaczek, Ewa; Pech, Paweł

    2014-01-01

    The utility of phytocenotic indices in the diagnosis and classification of forest sites might be limited because of vegetation degeneration in managed forests. However, even in secondary communities it may be possible to determine indicator species, although these may differ from typical and well known plant indicators. The aim of this work was to assess the vegetation diversity of Scots pine stands in representative forest site types along a moisture and fertility gradient. In total ...

  3. Dynamic growth and yield model for Black pine stands in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Mora, J. V.; Rio, M. del; Bravo-Oviedo, A.

    2012-07-01

    In a forestry context, modelling stand development over time relies on estimates of different stand characteristics obtained from equations which usually constitute a multivariate system. In this study we have developed a stand growth model for even-aged stands of Black pine (Pinus nigra Arn.) in Spain. The 53 plots used to fit the equations came from the permanent sample plot network established by the Forest Research Centre (INIA) in 1963 and 1964 in the main distribution regions of Black pine. The model is made up of a system of equations to predict growth and yield in volume and basal area. In the fitting phase we took into account the correlation between the measurements within the same plot and the cross-equation residual correlations. The model incorporates a control function to estimate the thinning effect and a function for predicting the reduction in tree number due to regular mortality. In addition, we use the three parameter Weibull distribution function to estimate the number of trees in each diameter class by recovering the parameters using the moment method. The developed model is useful for simulating the evolution of even-aged stands with and without thinnings and allows the estimation of number of trees by diameter classes. (Author) 44 refs.

  4. Does prescribed burning affect leaf secondary metabolites in pine stands?

    Science.gov (United States)

    Lavoir, A V; Ormeño, E; Pasqualini, V; Ferrat, L; Greff, S; Lecareux, C; Vila, B; Mévy, J P; Fernandez, C

    2013-03-01

    Prescribed burning (PB) is gaining popularity as a low-cost forest protection measure that efficiently reduces fuel build-up, but its effects on tree health and growth are poorly understood. Here, we evaluated the impact of PB on plant defenses in Mediterranean pine forests (Pinus halepensis and P. nigra ssp. laricio). These chemical defenses were estimated based on needle secondary metabolites (terpenes and phenolics including flavonoids) and discussed in terms of chlorophyll fluorescence and soil nutrients. Three treatments were applied: absence of burning (control plots); single burns (plots burned once); and repeated burns (plots burned twice). For single burns, we also explored changes over time. In P. laricio, PB tended to trigger only minor modifications consisting exclusively of short-lived increases (observed within 3 months after PB) in flavonoid index, possibly due to the leaf temperature increase during PB. In P. halepensis, PB had detrimental effects on physiological performance, consisting of (i) significant decreases in actual PSII efficiency (ΦPSII) in light-adapted conditions after repeated PB, and (ii) short-lived decreases in variable-to-maximum fluorescence ratio (Fv/Fm) after single PB, indicating that PB actually stressed P. halepensis trees. Repeated PB also promoted terpene-like metabolite production, which increased 2 to 3-fold compared to control trees. Correlations between terpene metabolites and soil chemistry were found. These results suggest that PB impacts needle secondary metabolism both directly (via a temperature impact) and indirectly (via soil nutrients), and that these impacts vary according to species/site location, frequency and time elapsed since last fire. Our findings are discussed with regard to the use of PB as a forest management technique and its consequences on plant investment in chemical defenses.

  5. Whitebark pine mortality related to white pine blister rust, mountain pine beetle outbreak, and water availability

    Science.gov (United States)

    Shanahan, Erin; Irvine, Kathryn M.; Thoma, David P.; Wilmoth, Siri K.; Ray, Andrew; Legg, Kristin; Shovic, Henry

    2016-01-01

    Whitebark pine (Pinus albicaulis) forests in the western United States have been adversely affected by an exotic pathogen (Cronartium ribicola, causal agent of white pine blister rust), insect outbreaks (Dendroctonus ponderosae, mountain pine beetle), and drought. We monitored individual trees from 2004 to 2013 and characterized stand-level biophysical conditions through a mountain pine beetle epidemic in the Greater Yellowstone Ecosystem. Specifically, we investigated associations between tree-level variables (duration and location of white pine blister rust infection, presence of mountain pine beetle, tree size, and potential interactions) with observations of individual whitebark pine tree mortality. Climate summaries indicated that cumulative growing degree days in years 2006–2008 likely contributed to a regionwide outbreak of mountain pine beetle prior to the observed peak in whitebark mortality in 2009. We show that larger whitebark pine trees were preferentially attacked and killed by mountain pine beetle and resulted in a regionwide shift to smaller size class trees. In addition, we found evidence that smaller size class trees with white pine blister rust infection experienced higher mortality than larger trees. This latter finding suggests that in the coming decades white pine blister rust may become the most probable cause of whitebark pine mortality. Our findings offered no evidence of an interactive effect of mountain pine beetle and white pine blister rust infection on whitebark pine mortality in the Greater Yellowstone Ecosystem. Interestingly, the probability of mortality was lower for larger trees attacked by mountain pine beetle in stands with higher evapotranspiration. Because evapotranspiration varies with climate and topoedaphic conditions across the region, we discuss the potential to use this improved understanding of biophysical influences on mortality to identify microrefugia that might contribute to successful whitebark pine conservation

  6. CO2 AND N-FERTILIZATION EFFECTS ON FINE ROOT LENGTH, PRODUCTION, AND MORTALITY: A 4-YEAR PONDEROSA PINE STUDY

    Science.gov (United States)

    We conducted a 4-year study of Pinus ponderosa fine root (<2 mm) responses to atmospheric CO2 and N-fertilization. Seedlings were grown in open-top chambers at 3 CO2 levels (ambient, ambient+175 mol/mol, ambient+350 mol/mol) and 3 N-fertilization levels (0, 10, 20 g?m-2?yr-1). ...

  7. Soil pCO2, soil respiration, and root activity in CO2 - fumigated and nitrogen-fertilized ponderosa pine

    Science.gov (United States)

    Dale Johnson; Donn Geisinger; Roger Walker; John Newman; James Vose; Katherine Elliott; Timothy Ball

    1994-01-01

    The purpose of this paper is to describe the effects of C02 and N treatments on soil pC02, calculated CO2 efflux, root biomass and soil carbon in open-top chambers planted with Pinus ponderosa seedlings. Based upon the literature, it was hypothesized that both elevated CO...

  8. Molecular approach to characterize ectomycorrhizae fungi from Mediterranean pine stands in Portugal

    Directory of Open Access Journals (Sweden)

    Carla Ragonezi

    2013-01-01

    Full Text Available Stone pine (Pinus pinea L., like other conifers, forms ectomycorrhizas (ECM, which have beneficial impact on plant growth in natural environments and forest ecosystems. An in vitro co-culture of stone pine microshoots with pure mycelia of isolated ECM sporocarps was used to overcome the root growth cessation not only in vitro but also to improve root development during acclimation phase. Pisolithus arhizus (Scop. Rauschert and Lactarius deliciosus (L. ex Fr. S.F. Gray fungi, were collected, pure cultured and used in in vitro co-culture with stone pine microshoots. Samples of P. arhizus and L. deliciosus for the in vitro co-cultures were collected from the pine stands southwest Portugal. The in situ characterization was based on their morphotypes. To confirm the identity of the collected material, ITS amplification was applied using the pure cultures derived from the sporocarps. Additionally, a molecular profile using PCR based genomic fingerprinting comparison was executed with other genera of Basidiomycetes and Ascomycetes. Our results showed the effectiveness of the techniques used to amplify DNA polymorphic sequences, which enhances the characterization of the genetic profile of ECM fungi and also provides an option to verify the fungus identity at any stage of plant mycorrhization.

  9. Molecular approach to characterize ectomycorrhizae fungi from Mediterranean pine stands in Portugal

    Science.gov (United States)

    Ragonezi, Carla; Caldeira, A. Teresa; Martins, M. Rosário; Salvador, Cátia; Santos-Silva, Celeste; Ganhão, Elsa; Klimaszewska, Krystyna; Zavattieri, Amely

    2013-01-01

    Stone pine (Pinus pinea L.), like other conifers, forms ectomycorrhizas (ECM), which have beneficial impact on plant growth in natural environments and forest ecosystems. An in vitro co-culture of stone pine microshoots with pure mycelia of isolated ECM sporocarps was used to overcome the root growth cessation not only in vitro but also to improve root development during acclimation phase. Pisolithus arhizus (Scop.) Rauschert and Lactarius deliciosus (L. ex Fr.) S.F. Gray fungi, were collected, pure cultured and used in in vitro co-culture with stone pine microshoots. Samples of P. arhizus and L. deliciosus for the in vitro co-cultures were collected from the pine stands southwest Portugal. The in situ characterization was based on their morphotypes. To confirm the identity of the collected material, ITS amplification was applied using the pure cultures derived from the sporocarps. Additionally, a molecular profile using PCR based genomic fingerprinting comparison was executed with other genera of Basidiomycetes and Ascomycetes. Our results showed the effectiveness of the techniques used to amplify DNA polymorphic sequences, which enhances the characterization of the genetic profile of ECM fungi and also provides an option to verify the fungus identity at any stage of plant mycorrhization. PMID:24294266

  10. Impact of mountain pine beetle outbreaks on forest albedo and radiative forcing, as derived from Moderate Resolution Imaging Spectroradiometer, Rocky Mountains, USA

    Science.gov (United States)

    Vanderhoof, M.; Williams, C. A.; Ghimire, B.; Rogan, J.

    2013-12-01

    pine beetle (Dendroctonus ponderosae) outbreaks in North America are widespread and have potentially large-scale impacts on albedo and associated radiative forcing. Mountain pine beetle outbreaks in Colorado and southern Wyoming have resulted in persistent and significant increases in both winter albedo (change peaked 10 years post outbreak at 0.06 ± 0.01 and 0.05 ± 0.01, in lodgepole pine (Pinus contorta) and ponderosa pine (Pinus ponderosa) stands, respectively) and spring albedo (change peaked 10 years post outbreak at 0.06 ± 0.01 and 0.04 ± 0.01, in lodgepole pine and ponderosa pine stands, respectively). Instantaneous top-of-atmosphere radiative forcing peaked for both lodgepole pine and ponderosa pine stands in winter at 10 years post outbreak at -1.7 ± 0.2 W m-2 and -1.4 ± 0.2 W m-2, respectively. The persistent increase in albedo with time since mountain pine beetle disturbance combined with the continued progression of the attack across the landscape from 1994-2011 resulted in an exponential increase in winter and annual radiative cooling (MW) over time. In 2011 the rate of radiative forcing within the study area reached -982.7 ± 139.0 MW, -269.8 ± 38.2 MW, -31.1 ± 4.4 MW, and -147.8 ± 20.9 MW in winter, spring, summer, and fall, respectively. An increase in radiative cooling has the potential to decrease sensible and/or latent heat flux by reducing available energy. Such changes could affect current mountain pine beetle outbreaks which are influenced by climatic conditions.

  11. Modeling loblolly pine aboveground live biomass in a mature pine-hardwood stand: a cautionary tale

    Science.gov (United States)

    D. C. Bragg

    2011-01-01

    Carbon sequestration in forests is a growing area of interest for researchers and land managers. Calculating the quantity of carbon stored in forest biomass seems to be a straightforward task, but it is highly dependent on the function(s) used to construct the stand. For instance, there are a number of possible equations to predict aboveground live biomass for loblolly...

  12. Leaf area and tree increment dynamics of even-aged and multiaged lodgepole pine stands in Montana

    Science.gov (United States)

    Cassandra L. Kollenberg; Kevin L. O' Hara

    1999-01-01

    Age structure and distribution of leaf area index (LAI) of even and multiaged lodgepole pine (Pinus contorta var. latifolia Engelm.) stands were examined on three study areas in western and central Montana. Projected leaf area was determined based on a relationship with sapwood cross-sectional area at breast height. Stand structure and LAI varied considerably between...

  13. Isolation and extreme sex-specific expression of cytochrome P450 genes in the bark beetle, Ips paraconfusus, following feeding on the phloem of host ponderosa pine, Pinus ponderosa.

    Science.gov (United States)

    Huber, D P W; Erickson, M L; Leutenegger, C M; Bohlmann, J; Seybold, S J

    2007-06-01

    We have identified cDNAs and characterized the expression of 13 novel cytochrome P450 genes of potential importance in host colonization and reproduction by the California fivespined ips, Ips paraconfusus. Twelve are of the Cyp4 family and one is of the Cyp9 family. Following feeding on host Pinus ponderosa phloem, bark beetle transcript levels of several of the Cyp4 genes increased or decreased in males only or in both sexes. In one instance (IparaCyp4A5) transcript accumulated significantly in females, but declined significantly in males. The Cyp9 gene (Cyp9T1) transcript levels in males were > 85 000 x higher at 8 h and > 25 000 x higher at 24 h after feeding compared with nonfed controls. Transcript levels in females were approximately 150 x higher at 24 h compared with nonfed controls. Cyp4G27 transcript was present constitutively regardless of sex or feeding and served as a better housekeeping gene than beta-actin or 18S rRNA for the real-time TaqMan polymerase chain reaction analysis. The expression patterns of Cyp4AY1, Cyp4BG1, and, especially, Cyp9T1 in males suggest roles for these genes in male-specific aggregation pheromone production. The differential transcript accumulation patterns of these bark beetle P450s provide insight into ecological interactions of I. paraconfusus with its host pines.

  14. Rehabilitation of Understocked Loblolly-Shortleaf Pine Stands - I. Recently Cutover Natural Stands

    Science.gov (United States)

    James B. Baker; Michael G. Shelton

    1998-01-01

    A 1988 USDA Forest Service report indicated that 22% (40 million ac) of the commercial timberland in the South was understocked (less than 60% stocking) with desirable tree species for timber production (USDA Forest Service 1988). The understocked stands are usually the result of past har-vesting practices, natural catastrophes, or regeneration fail-ures. Understocked...

  15. Hybridization in naturally regenerated shortleaf pine as affected by the distance to nearby artificially regenerated stands of loblolly pine

    Science.gov (United States)

    John F. Stewart; Charles G. Tauer; James M. Guldin; C. Dana Nelson

    2013-01-01

    The natural range of shortleaf pine encompasses 22 states from New York to Texas, second only to eastern white pine in the eastern United States. It is a species of minor and varying occurrence in most of these states usually found in association with other pines, but it is the only naturally occurring pine in the northwestern part of its range in Oklahoma, Arkansas,...

  16. Regeneration of Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) three decades after stand-replacing fires

    Science.gov (United States)

    Jonathan D. Coop; Anna W. Schoettle

    2009-01-01

    Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) are important highelevation pines of the southern Rockies that are forecast to decline due to the recent spread of white pine blister rust (Cronartium ribicola) into this region. Proactive management strategies to promote the evolution of rust resistance and maintain ecosystem function...

  17. Change in soil fungal community structure driven by a decline in ectomycorrhizal fungi following a mountain pine beetle (Dendroctonus ponderosae) outbreak.

    Science.gov (United States)

    Pec, Gregory J; Karst, Justine; Taylor, D Lee; Cigan, Paul W; Erbilgin, Nadir; Cooke, Janice E K; Simard, Suzanne W; Cahill, James F

    2017-01-01

    Western North American landscapes are rapidly being transformed by forest die-off caused by mountain pine beetle (Dendroctonus ponderosae), with implications for plant and soil communities. The mechanisms that drive changes in soil community structure, particularly for the highly prevalent ectomycorrhizal fungi in pine forests, are complex and intertwined. Critical to enhancing understanding will be disentangling the relative importance of host tree mortality from changes in soil chemistry following tree death. Here, we used a recent bark beetle outbreak in lodgepole pine (Pinus contorta) forests of western Canada to test whether the effects of tree mortality altered the richness and composition of belowground fungal communities, including ectomycorrhizal and saprotrophic fungi. We also determined the effects of environmental factors (i.e. soil nutrients, moisture, and phenolics) and geographical distance, both of which can influence the richness and composition of soil fungi. The richness of both groups of soil fungi declined and the overall composition was altered by beetle-induced tree mortality. Soil nutrients, soil phenolics and geographical distance influenced the community structure of soil fungi; however, the relative importance of these factors differed between ectomycorrhizal and saprotrophic fungi. The independent effects of tree mortality, soil phenolics and geographical distance influenced the community composition of ectomycorrhizal fungi, while the community composition of saprotrophic fungi was weakly but significantly correlated with the geographical distance of plots. Taken together, our results indicate that both deterministic and stochastic processes structure soil fungal communities following landscape-scale insect outbreaks and reflect the independent roles tree mortality, soil chemistry and geographical distance play in regulating the community composition of soil fungi. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  18. Observations and models of emissions of volatile terpenoid compounds from needles of ponderosa pine trees growing in situ: control by light, temperature and stomatal conductance

    Energy Technology Data Exchange (ETDEWEB)

    Harley, Peter; Eller, Allyson; Guenther, Alex; Monson, Russell K.

    2014-07-12

    Terpenoid emissions from ponderosa pine (Pinus ponderosa subsp. scopulorum) were measured in Colorado, USA over two growing seasons to evaluate the role of incident light, needle temperature and stomatal conductance in controlling emissions of 2-methyl-3-buten-2-ol (MBO) and several monoterpenes. MBO was the dominant daylight terpenoid emission, comprising on average 87% of the total flux, and diurnal variations were largely determined by light and temperature. During daytime, oxygenated monoterpenes (especially linalool) comprised up to 75% of the total monoterpenoid flux from needles. A significant fraction of monoterpenoid emissions was light dependent and 13CO2 labeling studies confirmed de novo production. Thus, modeling of monoterpenoid emissions required a hybrid model in which a significant fraction of emissions was dependent on both light and temperature, while the remainder was dependent on temperature alone. Experiments in which stomata were forced to close using abscisic acid demonstrated that MBO and a large fraction of the monoterpene flux, presumably linalool, could be limited at the scale of seconds to minutes by stomatal conductance. Using a previously published model of terpenoid emissions which explicitly accounts for the physico-chemical properties of emitted compounds, we are able to simulate these observed stomatal effects, whether induced through experimentation or arising under naturally fluctuation conditions of temperature and light. This study shows unequivocally that, under naturally occurring field conditions, de novo light dependent monoterpenes can comprise a large fraction of emissions. Differences between the monoterpene composition of ambient air and needle emissions imply a significant non-needle emission source enriched in Δ-3-carene.

  19. Penerapan Analisis Diskriminan dalam Pembedaan Kelas Umur Tegakan Pinus (Discriminant Analysist for Stand Class Age Distinction of Pine Stand

    Directory of Open Access Journals (Sweden)

    Priyanto .

    2011-01-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} This  study  describes the use of discriminant anylisis for pine (Pinus spp. stand class age distinction.    Aim of this  study were (1 to arrange stand age class based on variable of aerial photograph by non hierarchy cluster analysis,  and (2 to find out aerial  photograph variable contribute to stand age class distinction by discriminant analysis.    Data used in study was taken from  a  research  conducted by Adi (1998.   Pinus stand was located  in KPH Bandung Utara, West Java. The variable of aerial photograph that used in this analysis were tone, shape, texture, topography, pattern, crown, diameter and height. The result showed that validation analysis of discriminant function was significant.  Therefore, this function was applicable for grouping new object to stand age class based on discriminant score. Keywords: cluster analysis, discriminat analysis, stand age class, discriminant score

  20. Climatic factors controlling the productivity of pine stands. A model-based analysis

    International Nuclear Information System (INIS)

    McMurtrie, R.E.; Gholz, H.L.; Linder, S.; Gower, S.T.

    1994-01-01

    A process-based forest growth model, BIOMASS, is applied to stands of four pine species (Pinus elliottii, P. radiata, P. resinosa, and P. sylvestris) growing in five sub-tropical, temperate and boreal environments (in Australia, New Zealand, Florida, Sweden and Wisconsin). Measured annual above-ground net primary production (ANPP) at these sites ranges from 0.2 to 1.6 kg C m -2 . After establishing that simulated ANPP closely matches biomass production measured for the various stands, we analyse model runs to relate simulated productivity to absorbed photosynthetically-active radiation (APAR). Annual photosynthetic productivity (or gross primary production, GPP) simulated for the five stands is linearly related to utilizable APAR, derived by estimating the extent to which photosynthesis is limited by soil water deficit, high air saturation vapor deficit or low temperature. The reduction of GPP due to incomplete radiation interception is 10 to 25% for stands with high leaf area index (LAI) in Australia, New Zealand and Wisconsin and 50 to 60% for low LAI stands in Florida and Sweden. Gross carbon gain is reduced by a further 50 to 70% at sites experiencing cold winters (Sweden and Wisconsin), summer drought (Australia) or high summer humidity deficits (Australia and Wisconsin). Simulated carbon losses due to above-ground respiration average 50% of GPP, but are highly variable among the sites due to large differences in live biomass and tissue nitrogen concentrations. This results in a weaker relationship between simulated NPP and APAR. (au) 93 refs

  1. Long-Term Trends In Loblolly Pine Productivity And Stand Characteristics In Response To Stand Density And Fertilization In The Western Gulf Region

    Science.gov (United States)

    M.A. Sword; J. L. Chambers; Z. Tang; T. J. Dean; J. C. Goelz

    2002-01-01

    Two levels each of fertilization and stand density were established to create four environments in a 7-year-old loblolly pine plantation on a N and P deficient western Gulf Coastal Plain site in Louisiana. Levels of fertilization were no fertilization and application of 120 lb N and 134 lb P/ac. Levels of stand density were the original stocking (1,210 trees/ac), and...

  2. Feedbacks of windthrow for Norway spruce and Scots pine stands under changing climate

    DEFF Research Database (Denmark)

    Panferov, O.; Döring, C.; Rauch, E.

    2009-01-01

    is currently being developed at Göttingen University aims at providing a tool for the quantitative assessment of biotic and abiotic risks for forest ecosystems under the conditions of changing climate. In order to assess the future risks of wind damage the system employs a coupled modelling approach combining...... the turbulence model SCAlar DIStribution (SCADIS) with the soil–vegetation–atmosphere-transfer (SVAT) model BROOK 90. The present study investigates projections of wind damage in Solling, Germany under climate scenarios A1B and B1, taking into account the windthrow feedbacks—changes of microclimate as a result...... the probability of damage would be higher than under B1 and that under the same climate and soil conditions the risk for spruce stands would be higher than for pine stands of equal age. The degree of damage and feedback contribution as well as a sign of feedback in each particular case will strongly depend...

  3. Verbenone: Dose-Dependent Interruption of Pheromone-Based Attraction of Three Sympatric Species of Pine Bark Beetles (Coleoptera: Scolytidae)

    Science.gov (United States)

    Daniel R. Miller; John H. Borden; B. Staffan Lindgren

    1995-01-01

    Verbenone significantly reduced catches of Ips latidens (LeConte), I. pini (Say), and Dendroctonus ponderosae Hopkins in multiple-funnel traps, baited with aggregation pheromones, in stands of lodgepole pine in southern British Columbia. Interruption of attraction was dose dependent for all three species. There...

  4. Estimating aboveground tree biomass for beetle-killed lodgepole pine in the Rocky Mountains of northern Colorado

    Science.gov (United States)

    Woodam Chung; Paul Evangelista; Nathaniel Anderson; Anthony Vorster; Hee Han; Krishna Poudel; Robert Sturtevant

    2017-01-01

    The recent mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic has affected millions of hectares of conifer forests in the Rocky Mountains. Land managers are interested in using biomass from beetle-killed trees for bioenergy and biobased products, but they lack adequate information to accurately estimate biomass in stands with heavy mortality. We...

  5. Feedbacks of windthrow for Norway spruce and Scots pine stands under changing climate

    International Nuclear Information System (INIS)

    Panferov, O; Rauch, E; Doering, C; Ahrends, B; Sogachev, A

    2009-01-01

    Wind damage is one of the major natural disturbances that can occur worldwide in most types of forests. Enhanced management using adequate decision support systems (DSS) can considerably reduce the risk of windthrow. The decision support system 'Forest and Climate Change' (DSS-WuK) which is currently being developed at Goettingen University aims at providing a tool for the quantitative assessment of biotic and abiotic risks for forest ecosystems under the conditions of changing climate. In order to assess the future risks of wind damage the system employs a coupled modelling approach combining the turbulence model SCAlar DIStribution (SCADIS) with the soil-vegetation-atmosphere-transfer (SVAT) model BROOK 90. The present study investigates projections of wind damage in Solling, Germany under climate scenarios A1B and B1, taking into account the windthrow feedbacks-changes of microclimate as a result of tree fall and consequent stabilization or destabilization of a forest stand. The results of the study indicate that in Solling the risk of windthrow for spruce and pine forest stands is likely to increase considerably during the 21st century. The general tendencies indicate that under A1B the probability of damage would be higher than under B1 and that under the same climate and soil conditions the risk for spruce stands would be higher than for pine stands of equal age. The degree of damage and feedback contribution as well as a sign of feedback in each particular case will strongly depend on the particular local or regional combination of climatic and soil factors with tree species, age and structure. For Solling the positive feedback to local climatic forcing is found. The feedback contributes considerably (up to 6% under given conditions) to the projected forest damage and cannot be neglected. Therefore, the adequate projection of future damage probabilities can be performed only with a process-based coupled soil-atmosphere model with corresponding high spatial

  6. Pinus albicaulis Engelm. (Whitebark Pine in Mixed-Species Stands throughout Its US Range: Broad-Scale Indicators of Extent and Recent Decline

    Directory of Open Access Journals (Sweden)

    Sara A. Goeking

    2018-03-01

    Full Text Available We used data collected from >1400 plots by a national forest inventory to quantify population-level indicators for a tree species of concern. Whitebark pine (Pinus albicaulis has recently experienced high mortality throughout its US range, where we assessed the area of land with whitebark pine present, size-class distribution of individual whitebark pine, growth rates, and mortality rates, all with respect to dominant forest type. As of 2016, 51% of all standing whitebark pine trees in the US were dead. Dead whitebark pines outnumbered live ones—and whitebark pine mortality outpaced growth—in all size classes ≥22.8 cm diameter at breast height (DBH, across all forest types. Although whitebark pine occurred across 4.1 million ha in the US, the vast majority of this area (85% and of the total number of whitebark pine seedlings (72% fell within forest types other than the whitebark pine type. Standardized growth of whitebark pines was most strongly correlated with the relative basal area of whitebark pine trees (rho = 0.67; p < 0.01, while both standardized growth and mortality were moderately correlated with relative whitebark pine stem density (rho = 0.39 and 0.40; p = 0.031 and p < 0.01, respectively. Neither growth nor mortality were well correlated with total stand basal area, total stem density, or stand mean diameter. The abundance, extent, and relative growth vs. mortality rates of whitebark pine in multiple forest types presents opportunities for management to encourage whitebark pine recruitment in mixed-species stands. The lodgepole pine forest type contained more whitebark pine seedlings (35% than any other forest type, suggesting that this forest type represents a potential management target for silvicultural treatments that seek to facilitate the recruitment of whitebark pine seedlings into larger size classes. National forest inventories in other countries may use a similar approach to assess species of concern.

  7. Response of Pinus ponderosa Seedlings to Stylet-Bearing Nematodes

    Science.gov (United States)

    Viglierchio, D. R.

    1979-01-01

    Of 12 stylet-bearing nematodes used for inoculations, Pratylenchus penetrans, P. brachyurus, P. vulnus, Ditylenchus destructor, Meloidogyne incognita, M. javanica, and M. hapla reproduced on Pinus ponderosa, while Xiphinema index, Aphelenchus avenae, Paratylenehus neoamblycephalus, Tylenchulus semipenetrans, and Macroposthonia xenoplax did not. P. vulnus, P. brachyurus, P. penetrans, A. avenae, D. destructor, T. semipenetrans, and P. neoamblycephalus significantly suppressed both the shoot and root wet weights of ponderosa pine seedlings obtained from stands in five different locations. X. index significantly suppressed root wet weights, M. xenoplax siguificantly suppressed shoot wet weight, and M. incognita, M. javanica, and M. hapla suppressed neither at the inoculation levels used. Injurious nematodes tended to suppress root growth more than shoot growth. Seedlings from two locations produced greater shoot growth wet weight than did seedlings from the other three locations. The more injurious nematodes tended to cause an increase in the water content of shoots. Frequency analyses of seedling population shoot-root ratios indicated that ponderosa pine seedlings could be selected for better shoot-root ratios as well as for resistance to several pathogenic nematodes. PMID:19300659

  8. Overstory tree status following thinning and burning treatments in mixed pine-hardwood stands on the William B. Bankhead National Forest, Alabama

    Science.gov (United States)

    Callie Jo Schweitzer; Yong Wang

    2013-01-01

    Prescribed burning and thinning are intermediate stand treatments whose consequences when applied in mixed pine-hardwood stands are unknown. The William B. Bankhead National Forest in northcentral Alabama has undertaken these two options to move unmanaged, 20- to 50-year-old loblolly pine (Pinus taeda L.) plantations towards upland hardwood-dominated...

  9. Proteomics indicators of the rapidly shifting physiology from whole mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae, adults during early host colonization.

    Directory of Open Access Journals (Sweden)

    Caitlin Pitt

    Full Text Available We developed proteome profiles for host colonizing mountain pine beetle adults, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae. Adult insects were fed in pairs on fresh host lodgepole pine, Pinus contorta Dougl. ex Loud, phloem tissue. The proteomes of fed individuals were monitored using iTRAQ and compared to those of starved beetles, revealing 757 and 739 expressed proteins in females and males, respectively, for which quantitative information was obtained. Overall functional category distributions were similar for males and females, with the majority of proteins falling under carbohydrate metabolism (glycolysis, gluconeogenesis, citric acid cycle, structure (cuticle, muscle, cytoskeleton, and protein and amino acid metabolism. Females had 23 proteins with levels that changed significantly with feeding (p<0.05, FDR<0.20, including chaperones and enzymes required for vitellogenesis. In males, levels of 29 proteins changed significantly with feeding (p<0.05, FDR<0.20, including chaperones as well as motor proteins. Only two proteins, both chaperones, exhibited a significant change in both females and males with feeding. Proteins with differential accumulation patterns in females exhibited higher fold changes with feeding than did those in males. This difference may be due to major and rapid physiological changes occurring in females upon finding a host tree during the physiological shift from dispersal to reproduction. The significant accumulation of chaperone proteins, a cytochrome P450, and a glutathione S-transferase, indicate secondary metabolite-induced stress physiology related to chemical detoxification during early host colonization. The females' activation of vitellogenin only after encountering a host indicates deliberate partitioning of resources and a balancing of the needs of dispersal and reproduction.

  10. A review of thinning effects on Scots pine stands: From growth and yield to new challenges under global change

    Directory of Open Access Journals (Sweden)

    Miren del Río

    2017-10-01

    Full Text Available Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L. stands have been carried out since long in different regions of its distribution. The aim of this paper is to gather the knowledge about the thinning effects on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the framework of climate change. Area of study: The review covered studies from different regions of the distribution area of Scots pine Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L. stands have been carried out for many years in different regions of its distribution. The aim of this paper is to gather knowledge regarding the effects of thinning on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the context of climate change. Area of study: The review covers studies from different regions of the distribution area of Scots pine Material and methods: We reviewed the effect of thinning on four aspects: growth and yield, stability against snow and wind, response to drought, and ecosystem services. Main results: Heavy thinning involves a loss in volume yield, although the magnitude depends on the region, site and stand age. Thinning generally does not affect dominant height while the positive effect on tree diameter depends on the thinning regime. The stability of the stand against snow and wind is lower after the first thinning and increases in the long term. The impact of extreme droughts on tree growth is lower in thinned stands, which is linked to a better capacity to recover after the drought. Thinning generally reduces the wood quality, litter mass, and stand structural diversity, while having neutral or positive effects on other ecosystem services, although these effects can vary depending on the thinning regime. However, scarce information is available for most of the ecosystem services. Research highlight: Existing thinning experiments in

  11. A review of thinning effects on Scots pine stands: From growth and yield to new challenges under global change

    International Nuclear Information System (INIS)

    Miren del Río, M.P.; Bravo-Oviedo, Andrés; Pretzsch, Hans; Löf, Magnus; Ruiz-Peinado, Ricardo

    2017-01-01

    Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L.) stands have been carried out since long in different regions of its distribution. The aim of this paper is to gather the knowledge about the thinning effects on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the framework of climate change. Area of study: The review covered studies from different regions of the distribution area of Scots pine Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L.) stands have been carried out for many years in different regions of its distribution. The aim of this paper is to gather knowledge regarding the effects of thinning on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the context of climate change. Area of study: The review covers studies from different regions of the distribution area of Scots pine Material and methods: We reviewed the effect of thinning on four aspects: growth and yield, stability against snow and wind, response to drought, and ecosystem services. Main results: Heavy thinning involves a loss in volume yield, although the magnitude depends on the region, site and stand age. Thinning generally does not affect dominant height while the positive effect on tree diameter depends on the thinning regime. The stability of the stand against snow and wind is lower after the first thinning and increases in the long term. The impact of extreme droughts on tree growth is lower in thinned stands, which is linked to a better capacity to recover after the drought. Thinning generally reduces the wood quality, litter mass, and stand structural diversity, while having neutral or positive effects on other ecosystem services, although these effects can vary depending on the thinning regime. However, scarce information is available for most of the ecosystem services. Research highlight: Existing thinning experiments in Scots pine stands

  12. A review of thinning effects on Scots pine stands: From growth and yield to new challenges under global change

    Energy Technology Data Exchange (ETDEWEB)

    Miren del Río, M.P.; Bravo-Oviedo, Andrés; Pretzsch, Hans; Löf, Magnus; Ruiz-Peinado, Ricardo

    2017-11-01

    Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L.) stands have been carried out since long in different regions of its distribution. The aim of this paper is to gather the knowledge about the thinning effects on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the framework of climate change. Area of study: The review covered studies from different regions of the distribution area of Scots pine Aim of the study: Thinning experiments in Scots pine (Pinus sylvestris L.) stands have been carried out for many years in different regions of its distribution. The aim of this paper is to gather knowledge regarding the effects of thinning on Scots pine stands, from the effects on growth and yield to the provision of ecosystem services in the context of climate change. Area of study: The review covers studies from different regions of the distribution area of Scots pine Material and methods: We reviewed the effect of thinning on four aspects: growth and yield, stability against snow and wind, response to drought, and ecosystem services. Main results: Heavy thinning involves a loss in volume yield, although the magnitude depends on the region, site and stand age. Thinning generally does not affect dominant height while the positive effect on tree diameter depends on the thinning regime. The stability of the stand against snow and wind is lower after the first thinning and increases in the long term. The impact of extreme droughts on tree growth is lower in thinned stands, which is linked to a better capacity to recover after the drought. Thinning generally reduces the wood quality, litter mass, and stand structural diversity, while having neutral or positive effects on other ecosystem services, although these effects can vary depending on the thinning regime. However, scarce information is available for most of the ecosystem services. Research highlight: Existing thinning experiments in Scots pine stands

  13. Effects of a Severe Mountain Pine Beetle Epidemic in Western Alberta, Canada under Two Forest Management Scenarios

    Directory of Open Access Journals (Sweden)

    Richard R. Schneider

    2010-01-01

    Full Text Available We used a simulation model to investigate possible effects of a severe mountain pine beetle (Dendroctonus ponderosae Hopkins epidemic under two management scenarios in Alberta, Canada. Our simulated outbreak was based on the current epidemic in British Columbia, which may kill close to 80% of the province's pine volume. Our two management scenarios were conventional harvest and a pine-reduction strategy modeled on a component of Alberta's Mountain Pine Beetle Management Strategy. The pine strategy seeks to reduce the number of susceptible pine stands by 75% over the next 20 years through targeted harvesting by the forest industry. Our simulations showed that the pine strategy could not be effectively implemented, even if the onset of the beetle outbreak was delayed for 20 years. Even though we increased mill capacity by 20% and directed all harvesting to high volume pine stands during the pine strategy's surge cut, the amount of highly susceptible pine was reduced by only 43%. Additional pine volume remained within mixed stands that were not targeted by the pine strategy. When the outbreak occurred in each scenario, sufficient pine remained on the landscape for the beetle to cause the timber supply to collapse. Alternative management approaches and avenues for future research are discussed.

  14. Determining Nutrient Requirements For Intensively Managed Loblolly Pine Stands Using the SSAND (Soil Supply and Nutrient Demand) Model

    Science.gov (United States)

    Hector G. Adegbidi; Nicholas B. Comerford; Hua Li; Eric J. Jokela; Nairam F. Barros

    2002-01-01

    Nutrient management represents a central component of intensive silvicultural systems that are designed to increase forest productivity in southern pine stands. Forest soils throughout the South are generally infertile, and fertilizers may be applied one or more times over the course of a rotation. Diagnostic techniques, such as foliar analysis and soil testing are...

  15. Irrigation and fertilization effects on foliar and soil carbon and nitrogen isotope ratios in a loblolly pine stand

    Science.gov (United States)

    Woo-Jung Choi; Scott X. Chang; H. Lee Allen; Daniel L. Kelting; Hee-Myong Ro

    2005-01-01

    We examined 813C and 815N in needle (current and 1-year-old) and soil samples collected on two occasions (July and September 1999) from a 15-year-old loblolly pine (Pinus taeda L.) stand in an irrigation and fertilization experiment to investigate whether these treatments leave specific isotope signals in...

  16. Twenty-four years after theYellowstone Fires: Are postfire lodgepole pine stands converging in structure and function?

    Science.gov (United States)

    Turner, Monica G; Whitby, Timothy G; Tinker, Daniel B; Romme, William H

    2016-05-01

    Disturbance and succession have long been of interest in ecology, but how landscape patterns of ecosystem structure and function evolve following large disturbances is poorly understood. After nearly 25 years, lodgepole pine (Pinus contorta var. latifolia) forests that regenerated after the 1988 Yellowstone Fires (Wyoming, USA) offer a prime opportunity to track the fate of disturbance-created heterogeneity in stand structure and function in a wilderness setting. In 2012, we resampled 72 permanent plots to ask (1) How have postfire stand structure and function changed between 11 and 24 yr postfire, and what variables explain these patterns and changes? (2) How has landscape-level (among-stand) variability in postfire stand structure and function changed between 11 and 24 yr postfire? We expected to see evidence of convergence beginning to emerge, but also that initial postfire stem density would still determine trajectories of biomass accumulation. After 24 yr, postfire lodgepole pine density remained very high (mean = 21,738 stems/ha, range = 0-344,067 stems/ha). Stem density increased in most plots between 11 and 24 yr postfire, but declined sharply where 11-yr-postfire stem density was > 72,000 stems/ha. Stems were small in high-density stands, but stand-level lodgepole pine leaf area, foliage biomass, and live aboveground biomass increased over time and with increasing stem density. After 24 yr, mean annual lodgepole pine aboveground net primary production (ANPP) was high (mean = 5 Mg · ha⁻¹ · yr⁻¹, range = 0-16.5 Mg · ha⁻¹ · yr⁻¹). Among stands, lodgepole pine ANPP increased with stem density, which explained 69% of the variation; another 8% of the variation was explained by environmental covariates. Early patterns of postfire lodgepole pine regeneration, which were contingent on prefire serotiny and fire severity, remained the dominant driver of stand structure and function. We observed mechanisms that would lead to convergence in stem density

  17. Density, heating value, and composition of pellets made from lodgepole pine (Pinus concorta Douglas) infested with mountain pine beetle (Dendroctonus ponderosae Hopkins)

    Energy Technology Data Exchange (ETDEWEB)

    Zaini, P.; Kadla, J. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Wood Science; Sokansanj, S. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering; Oak Ridge National Laboratory, Oak Ridge, TN (United States). Environmental Sciences Div., Bioenergy Resource and Engineering Systems; Bi, X.; Lim, C.J. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering; Mani, S. [Georgia Univ., Athens, GA (United States). Faculty of Engineering; Melin, S. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering; Delta Research Corp., Delta, BC (Canada)

    2008-07-01

    BC is currently experiencing the largest recorded mountain pine beetle (MPB) infestation in North America that has killed nearly 7 million hectares of pine. The dead trees gradually lose their suitability for dimension lumber and pulp chips due to excessive cracking and spoilage. The economic losses can be partly averted by recovering the killed wood and processing it into pellets for bioenergy and other applications. Currently, Canada exports roughly 750,000 tons of wood pellets to Europe as a fuel for heat and power. The most important physical properties of wood pellets are bulk and pellet density, heating value, moisture content, and durability. In light of the chemical and structural changes reported with MPB attack, it is important to develop engineering data on properties of MPB-affected pine for wood pellets. The objective of this study was to compare chemical composition, density, and heat value of pellets made from MPB-infested wood and to compare these properties with those measured for pellets made from uninfested wood. Chemical analysis showed minor decrease in lignin and sugar contents of pellets made from MPB wood. Pellets made from MPB-infested pine had a mean value for density larger than those made from uninfested pine but the difference was not statistically significant. Heating values of the pellets from MPB-infested wood were similar to those measured for pellets from uninfested wood. A preliminary observation of mold growth did not show any further staining or other decay fungi growth for the pellets made from MPB-infested wood. The pellets made from MPB-infested wood were found to be similar to pellets made from uninfested wood in density, heating value, and most chemical constituents. The overall conclusion was that MBP infested wood can be used to produce comparable pellets to non infested wood pellets. 37 refs., 6 tabs., 2 figs.

  18. Effects of tree size and spatial distribution on growth of ponderosa pine forests under alternative management scenarios

    Science.gov (United States)

    C.W. Woodall; C.E. Fiedler; R.E. McRoberts

    2009-01-01

    Forest ecosystems may be actively managed toward heterogeneous stand structures to provide both economic (e.g., wood production and carbon credits) and environmental benefits (e.g., invasive pest resistance). In order to facilitate wider adoption of possibly more sustainable forest stand structures, defining growth expectations among alternative management scenarios is...

  19. Soil Respiration Changes after Prescribed Fires in Spanish Black Pine (Pinus nigra Arn. ssp. salzmannii Monospecific and Mixed Forest Stands

    Directory of Open Access Journals (Sweden)

    Pedro Antonio Plaza-Álvarez

    2017-07-01

    Full Text Available Soil respiration is a major carbon pathway sensitive to environmental changes. Using prescribed burnings to reduce fuel accumulation and lower risks of large-scale wildfires has recently become more important. Prescribed burning can significantly alter the soil environment, but its effect in practice on soil respiration is not sufficiently understood. We evaluated the effects of prescribed burning on soil respiration before and after burning (May–July 2016. Prescribed burning was conducted in two natural pine areas by comparing a mixed stand of Pinus nigra Arn. ssp. salzmannii with Pinus pinaster Ait. to a pure stand of Pinus nigra Arn. ssp. salzmannii in the central Iberian Peninsula. Soil respiration was measured by an EGM-4 (Environmental Gas Monitor infrared gas analyser in both burned and unburned (control plots. Burnings were low-intensity, and slightly more energetic in the pure stand given its larger litter volume. Post-burning soil respiration followed a similar evolution to that in the control plots, but was greater in the pure stand burned zone and slightly lower in the burned plots in the mixed stand. No significant differences were found in any stand. Soil respiration significantly changed in temporal evolution due to increasing temperatures when summer began. We conclude that prescribed fire induces no changes in SR immediately after fire. This study helps understand how prescribed burnings can affect soil respiration in pure and mixed Spanish black pine forest stands.

  20. Influence of coarse woody debris on the soricid community in southeastern Coastal Plain pine stands.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Justin, C.; Castleberry, Steven, B.; Kilgo, John, C.

    2010-07-01

    Shrew abundance has been linked to the presence of coarse woody debris (CWD), especially downed logs, in many regions in the United States. We investigated the importance of CWD to shrew communities in managed upland pine stands in the southeastern United States Coastal Plain. Using a randomized complete block design, 1 of the following treatments was assigned to twelve 9.3-ha plots: removal (n 5 3; all downed CWD _10 cm in diameter and _60 cm long removed), downed (n 5 3; 5-fold increase in volume of downed CWD), snag (n 5 3; 10-fold increase in volume of standing dead CWD), and control (n 5 3; unmanipulated). Shrews (Blarina carolinensis, Sorex longirostris, and Cryptotis parva) were captured over 7 seasons from January 2007 to August 2008 using drift-fence pitfall trapping arrays within treatment plots. Topographic variables were measured and included as treatment covariates. More captures of B. carolinensis were made in the downed treatment compared to removal, and captures of S. longirostris were greater in downed and snag compared to removal. Captures of C. parva did not differ among treatments. Captures of S. longirostris were positively correlated with slope. Our results suggest that abundance of 2 of the 3 common shrew species of the southeastern Coastal Plain examined in our study is influenced by the presence of CWD.

  1. Fine root dynamics in lodgepole pine and white spruce stands along productivity gradients in reclaimed oil sands sites.

    Science.gov (United States)

    Jamro, Ghulam Murtaza; Chang, Scott X; Naeth, M Anne; Duan, Min; House, Jason

    2015-10-01

    Open-pit mining activities in the oil sands region of Alberta, Canada, create disturbed lands that, by law, must be reclaimed to a land capability equivalent to that existed before the disturbance. Re-establishment of forest cover will be affected by the production and turnover rate of fine roots. However, the relationship between fine root dynamics and tree growth has not been studied in reclaimed oil sands sites. Fine root properties (root length density, mean surface area, total root biomass, and rates of root production, turnover, and decomposition) were assessed from May to October 2011 and 2012 using sequential coring and ingrowth core methods in lodgepole pine (Pinus contorta Dougl.) and white spruce (Picea glauca (Moench.) Voss) stands. The pine and spruce stands were planted on peat mineral soil mix placed over tailings sand and overburden substrates, respectively, in reclaimed oil sands sites in Alberta. We selected stands that form a productivity gradient (low, medium, and high productivities) of each tree species based on differences in tree height and diameter at breast height (DBH) increments. In lodgepole pine stands, fine root length density and fine root production, and turnover rates were in the order of high > medium > low productivity sites and were positively correlated with tree height and DBH and negatively correlated with soil salinity (P < 0.05). In white spruce stands, fine root surface area was the only parameter that increased along the productivity gradient and was negatively correlated with soil compaction. In conclusion, fine root dynamics along the stand productivity gradients were closely linked to stand productivity and were affected by limiting soil properties related to the specific substrate used for reconstructing the reclaimed soil. Understanding the impact of soil properties on fine root dynamics and overall stand productivity will help improve land reclamation outcomes.

  2. Whole System Carbon Exchange of Small Stands of Pinus Ponderosa Growing at Different CO(sub 2) concentrations in open top chambers; FINAL

    International Nuclear Information System (INIS)

    Ball, J. Timothy; Ross, Peter D.; Picone, John B.; Eichelmann, Hillar Y.; Ross, Gregory N.

    1996-01-01

    Functional understanding of the carbon cycle from the molecular to the global level is a high scientific priority requiring explanation of the relationship between fluxes at different spatial and temporal scales. We describe methods used to convert an open top chamber into both closed and open flow gas exchange systems utilized to measure such fluxes. The systems described consist of temporary modifications to an open top chamber, and are put in place for several days on one or several open top chambers. In the closed system approach, a chamber is quickly sealed for a short, predetermined time interval, the change in gas concentrations is measured, then the chamber is unsealed and ventilated. In the open flow system approach, airflow into the open top chamber is measured by trace gas injection, and the air stream concentration of CO(sub 2) and water vapor is measured before and after injection into the chamber. The closed chamber approach can resolve smaller fluxes, but causes transient increases in chamber air temperature, and has a high labor requirement. The open flow approach reduces the deviation of measuring conditions from ambient, may be semi-automated (requiring less labor), allows a more frequent sampling interval, but cannot resolve low fluxes well. Data demonstrating the capabilities of these systems show that, in open canopies of ponderosa pine, scaling fluxes from leaves to whole canopies is well approximated from summation of leaf P(sub s) rates. Flux measurements obtained from these systems can be a valuable contribution to our understanding whole system material fluxes, and challenge our understanding of ecosystem carbon budgets

  3. Natural regeneration and seed production of pine stands on the dumps of coal mining industry in Kuzbass

    Directory of Open Access Journals (Sweden)

    V. I. Ufimtsev

    2016-12-01

    Full Text Available On the basis of the accounting of undergrowth in 5 gradations of crown closure density of Scots pine (Pinus sylvest-ris L. stands, growing on the dumps in 4 ecological-geographic areas of Kuzbass, inverse relation of parameters of renewal from hydrothermal coefficient of the district is established. Optimum conditions develop in a steppe kernel where the number of shoots, seed production and undergrowth reaches 110 thousand trees per hectare with crown closure of 50 % and density of forest stand of 0.75 thousand trees of the II class of age on 1 hectare. At decrease or increase of forest canopy density of the main tree stand layer quantitative characteristics decrease. The smallest amount of undergrowth is recorded in the mountain-taiga area – from 0.4 to 23 thousand trees per hectare with a tendency to increase in the process of increasing crown closure. Areas of the northern forest-steppe and the southern forest-steppe on quantitative signs of renewal are intermediate. The number of undergrowth has high direct correlation dependence on the size of the current fructification of forest stands – around a steppe kernel ripens to 3.7 million seeds on 1 hectare, in mountain and taiga – to 0.39 million seeds on 1 hectare. Sowing qualities of seeds – the weight 1000, energy of germination and viability, and morphometric characteristics of 2-year seedlings, which are grown up from them – height, diameter and point of a vital state between ecological-geographic areas have no statistically reliable distinctions, but the characteristics stated above, than in the stands on zone soils. It testifies to usefulness of dumps’ conditions for natural regeneration of Scots pine, high actual reproductive opportunities for pine stands in forest-steppe areas and a steppe kernel, and also potential opportunities of the stands in the mountain and taiga region of the southern Kuzbass.

  4. Mountain Pine Beetle Fecundity and Offspring Size Differ Among Lodgepole Pine and Whitebark Pine Hosts

    OpenAIRE

    Gross, Donovan

    2008-01-01

    Whitebark pine (Pinus albicaulis Engelmann) is a treeline species in the central Rocky Mountains. Its occupation of high elevations previously protected whitebark pine from long-term mountain pine beetle outbreaks. The mountain pine beetle, however, is currently reaching outbreaks of record magnitude in high-elevation whitebark pine. We used a factorial laboratory experiment to compare mountain pine beetle (Dendroctonus ponderosae Hopkins) life history characteristics between a typical host, ...

  5. Ecological Responses to Five Years of Experimental Nitrogen Application in an Upland Jack-pine Stand

    Science.gov (United States)

    Melaschenko, N.; Berryman, S.; Straker, J.; Berg, K.; McDonough, A.; Watmough, S. A.

    2016-12-01

    A five-year experimental study was conducted to evaluate the response of an upland jack-pine (Pinus banksiana) forest to elevated levels of nitrogen (N) deposition in Northern Alberta. N deposition in the region is expected to increase with industrial expansion of oil sands activity, and there is regional interest to set N critical loads for sensitive ecosystems. In this study, N was applied as NH4NO3 above a jack-pine canopy via helicopter, annually for five years (2010-2015) at dosages equivalent to 5, 10, 15, 20 and 25 kg N ha-1 yr-1. Approximately 35% of the applied N was retained in the canopy while 65% reached understory vegetation dominated by lichens and mosses. We measured a significant increase in tissue N concentrations of common ground lichens (Cladonia mitis and C. stellaris) and ground moss (Pleurozium schreberi) as well as epiphytic lichens (Hypogymnia physodes and Evernia mesomorpha). On an annual basis, the applied N was primarily captured in the lichen and moss understory, dominated by C. mitis. In the highest treatments, N concentrations in C. mitis were 1.5-2.5 times greater than pre-treatment values. Peak N concentrations in the ground moss Pleurozium schreberi (1.4%) indicate that a threshold of N saturation was reached by year 3. We observed no changes in community composition of vascular and non-vascular plants, or changes in vascular plant tissue N. Chlorophyll levels in C. mitis increased with N treatment, but there was no indication of toxicity or changes to decomposition and growth. After five years of N application, only Peltigera polydactylon, a ground cyanolichen, appeared to be negatively impacted where the thalli showed necrosis at deposition loads >10kg N ha-1 yr-1. No changes to biomass or N ecosystem processes were observed. Based on these observations, we provide evidence that the first adverse ecological effects of N deposition in jack-pine stands occurred at deposition rates of 10 kg N ha-1 yr-1.

  6. Response of small mammal populations to fuel treatment and precipitation in a ponderosa pine forest, New Mexico

    Science.gov (United States)

    Karen E. Bagne; Deborah M. Finch

    2009-01-01

    Mechanical and fire treatments are commonly used to reduce fuels where land use practices have encouraged accumulation of woody debris and high densities of trees. Treatments focus on restoration of vegetation structure, but will also affect wildlife populations. Small mammal populations were monitored before and after dense tree stands were thinned on 2,800 ha in NM,...

  7. Season and severity of prescribed burn in ponderosa pine forests: implications for understory native and exotic plants.

    Science.gov (United States)

    Becky K. Kerns; Walter G. Thies; Christine G. Niwa

    2006-01-01

    We investigated herbaceous richness and cover in relation to fire season and severity, and other variables, five growing seasons following prescribed fires. Data were collected from six stands consisting of three randomly applied treatments: no burn, spring burn, and fall burn. Fall burns had significantly more exotic/native annual/biennial (an/bi) species and greater...

  8. Effects of feed supplemented with fermented pine needles (Pinus ponderosa) on growth performance and antioxidant status in broilers.

    Science.gov (United States)

    Wu, Q J; Wang, Z B; Wang, G Y; Li, Y X; Qi, Y X

    2015-06-01

    The objective of this study was to compare the effects of Aspergillus niger-fermented pine needles and nonfermented pine needles on growth performance and antioxidant capacity in broiler chicks. In total, 300 1-day-old broiler chicks were randomly allocated to 5 dietary treatments, which were then denoted as the control treatment (basal diet); the nonfermented treatment (containing 0.3% and 0.6% nonfermented treatment, respectively, in the starter and grower phase); or the fermented 1, fermented 2, or fermented 3 treatments. The fermented 1, fermented 2, and fermented 3 treatments contained 0.1, 0.3, and 0.5% fermented treatment, respectively, in the starter phase and 0.2, 0.6, and 1.0% fermented treatment, respectively, in the growth phase for 42 d. The results showed that fermentation treated supplementation had no adverse effect on the growth performance of broilers at 42 d of age. The activity of total nitric oxide synthase was significantly (P<0.05) decreased in the fermented treatment compared with the control and nonfermented treatments in broilers at 21 d of age. Compared with the control, broilers had higher (P<0.05) total superoxide dismutase activities and total antioxidant capacity when they were provided with either the fermented 2 or fermented 3 diet. The malondialdehyde content was significantly (P<0.05) decreased in the fermented 2 and fermented 3 treatments compared with the control and nonfermented treatments. It was concluded that the addition of fermented treatment to the diet could improve antioxidant capacity in broilers, as evidenced by the decrease in malondialdehyde and the increase in total superoxide dismutase activities; however, the effect of fermentation treatment on growth performance was negligible. © 2015 Poultry Science Association Inc.

  9. Stand Dynamics and Plant Associates of Loblolly Pine Plantations to Midrotation after Early Intensive Vegetation Management-A Southeastern United States Regional Study

    Science.gov (United States)

    James H. Miller; Bruce R. Zutter; Ray A. Newbold; M. Boyd Edwards; Shepard M. Zedaker

    2003-01-01

    Increasingly, pine plantations worldwide are grown using early control of woodv and/or herbaceous vegetation. Assuredsustainablepractices require long-term data on pine plantation development detailing patterns and processes to understand both crop-competition dynamics and the role of stand participants in providing multiple attributes such as biodiversity conservation...

  10. An examination of factors influencing the spatial distribution of foraging bats in pine stands in the southeastern United States.

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, Michael, A., Jr.

    2003-01-01

    Menzel, M.A. 2003. An examination of factors influencing the spatial distribution of foraging bats in pine stands in the Southeastern United States. Ph.D Dissertation. Davis College of Agriculture, Forestry and Consumer Sciences at West Virginia University, Morgantown, West Virginia. 336 pp. The general objective of this dissertation was to determine the effect of changes in forest structure on bat activity patterns in southern pine stands. Four sub studies are included in the dissertation: (1) An examination of the homerange size, habitat use and diet of four reproductively active male Rafinesque's big eared bats (Corynorhimus rafinesquii); (2) An examination of the diet of 5 reproductively active male Rafinesque's big eared bats; (3) A comparison of bat activity levels in the Coastal Plain of South Carolina among 5 vegetational community types: forested riparian areas, clearcuts, young pine plantations, mature plantations, and pine savannahs; (4) A summarization of information concerning the natural history of all bat species common in the SPR.

  11. Biomass equations and biomass expansion factors (BEFs) for pine (pinus spp.), spruce (picea spp.) and broadleaved dominated stands in Norway

    OpenAIRE

    Viken, Knut Ole

    2012-01-01

    Abstract The objectives of this study were (1) to develop models for estimation of stand-level tree biomass for spruce (picea spp.)- pine (pinus spp.)- and broadleaved-dominated forest in Norway and, (2) develop biomass expansion factors (BEFs; ratio of stem volume to biomass) which convert stem volume to whole tree biomass for Norwegian forest conditions. A dataset from a 5 year period (2006 – 2010) from the Norwegian National Forest Inventory (NFI) were used to develop the...

  12. Aboveground Tree Biomass for Pinus ponderosa in Northeastern California

    Directory of Open Access Journals (Sweden)

    Todd A. Hamilton

    2013-03-01

    Full Text Available Forest managers need accurate biomass equations to plan thinning for fuel reduction or energy production. Estimates of carbon sequestration also rely upon such equations. The current allometric equations for ponderosa pine (Pinus ponderosa commonly employed for California forests were developed elsewhere, and are often applied without consideration potential for spatial or temporal variability. Individual-tree aboveground biomass allometric equations are presented from an analysis of 79 felled trees from four separate management units at Blacks Mountain Experimental Forest: one unthinned and three separate thinned units. A simultaneous set of allometric equations for foliage, branch and bole biomass were developed as well as branch-level equations for wood and foliage. Foliage biomass relationships varied substantially between units while branch and bole biomass estimates were more stable across a range of stand conditions. Trees of a given breast height diameter and crown ratio in thinned stands had more foliage biomass, but slightly less branch biomass than those in an unthinned stand. The observed variability in biomass relationships within Blacks Mountain Experimental Forest suggests that users should consider how well the data used to develop a selected model relate to the conditions in any given application.

  13. Measurement and modelling of radiation transmission within a stand of maritime pine (Pinus pinaster Ait)

    International Nuclear Information System (INIS)

    Berbigier, P.; Bonnefond, J.M.

    1995-01-01

    A semi-empirical model of radiation penetration in a maritime pine canopy was developed so that mean solar (and net) radiation absorption by crowns and understorey could be estimated from above-canopy measurements only. Beam radiation Rb was assumed to penetrate the canopy according to Beer's law with an extinction coefficient of 0.32; this figure was found using non-linear regression techniques. For diffuse sky radiation, Beer's law was integrated over the sky vault assuming a SOC (standard overcast sky) luminance model; the upward and downward scattered radiative fluxes were obtained using the Kubelka-Munk equations and measurements of needle transmittance and reflectance. The penetration of net radiation within the canopy was also modelled. The model predicts the measured albedo of the stand very well. The estimation of solar radiation transmitted by the canopy was also satisfactory with the maximum difference between this and the mean output of mobile sensors at ground level being only 18 W m -2 . Due to the poor precision of net radiometers, the net radiation model could not be tested critically. However, as the modelled longwave radiation balance under the canopy is always between -10 and -20 Wm -2 , the below-canopy net radiation must be very close to the solar radiation balance. (author) [fr

  14. Chemodiversity of a Scots pine stand and implications for terpene air concentrations

    Science.gov (United States)

    Bäck, J.; Aalto, J.; Henriksson, M.; Hakola, H.; He, Q.; Boy, M.

    2012-02-01

    Atmospheric chemistry in background areas is strongly influenced by natural vegetation. Coniferous forests are known to produce large quantities of volatile vapors, especially terpenes. These compounds are reactive in the atmosphere, and contribute to the formation and growth of atmospheric new particles. Our aim was to analyze the variability of mono- and sesquiterpene emissions between Scots pine trees, in order to clarify the potential errors caused by using emission data obtained from only a few trees in atmospheric chemistry models. We also aimed at testing if stand history and seed origin has an influence on the chemotypic diversity. The inherited, chemotypic variability in mono- and sesquiterpene emission was studied in a seemingly homogeneous 48 yr-old stand in Southern Finland, where two areas differing in their stand regeneration history could be distinguished. Sampling was conducted in August 2009. Terpene concentrations in the air had been measured at the same site for seven years prior to branch sampling for chemotypes. Two main compounds, α-pinene and Δ3-carene formed together 40-97% of the monoterpene proportions in both the branch emissions and in the air concentrations. The data showed a bimodal distribution in emission composition, in particular in Δ3-carene emission within the studied population. 10% of the trees emitted mainly α-pinene and no Δ3-carene at all, whereas 20% of the trees where characterized as high Δ3-carene emitters (Δ3-carene forming >80% of total emitted monoterpene spectrum). An intermediate group of trees emitted equal amounts of both α-pinene and Δ3-carene. The emission pattern of trees at the area established using seeding as the artificial regeneration method differed from the naturally regenerated or planted trees, being mainly high Δ3-carene emitters. Some differences were also seen in e.g. camphene and limonene emissions between chemotypes, but sesquiterpene emissions did not differ significantly between trees

  15. NATIVE ROOT XYLEM EMBOLISM AND STOMATAL CLOSURE IN STANDS OF DOUGLAS-FIR AND PONDEROSA PINE: MITIGATION BY HYDRAULIC REDISTRIBUTION

    Science.gov (United States)

    Hydraulic redistribution (HR), the passive movement of water via roots from moist to drier portions of the soil, occurs in many ecosystems, influencing both plant and ecosystem-water use. We examined the effects of HR on root hydraulic functioning during drought in young and old-...

  16. Soil microbial activity in Aleppo pine stands naturally regenerated after fire: silvicultural management and induced drought

    Directory of Open Access Journals (Sweden)

    D. Moya

    2013-01-01

    Full Text Available In post-fire restoration, early monitoring is mandatory to check impacts and ecosystem responses to apply proper management according to social standards and ecological conditions. In areas where the natural regeneration was successful, excessive tree density can be found which induces to high intraspecific competence and assisted restoration management could be adequate. In addition, climatic changes will have large impacts on vegetation productivity and resilience since the regional models for south-eastern Spain predicts a rainfall decrease of about 20% and temperature increase of 4.5 ºC. The microbial biomass could be used as indicator of ecosystem recovery, since it is negatively affected by wildfires and depends on fire characteristics, vegetation and soil properties. Our aim is to determine how forest management may affect the ecosystem recovery in different climatic scenarios, included drought scenarios with and without forest management (thinning.We compared soil physicochemical properties and microbial activity in four scenarios: unmanaged and thinned stands in two rainfall scenarios (under induced drought. The study areas were set close to Yeste (Albacete where Aleppo pine forest were burned in summer 1994 (nearly 14000 ha. We set sixteen rectangular plots (150 m2; 15 m ×10 m implementing experimental silvicultural treatments: thinning eight plots in 2004, reducing the naturally recovered tree density from about 12000 to 1600 pine trees ha-1. In addition, in half the plots, we induced drought conditions from about 500 to 400 mm (20% from March 2009. In every plot, we monitored temperature at ground level (Ts, 10 cm depth (T10d and soil relative humidity (RH. Taking into account season of the year and canopy coverage, we collected soil samples in mid-winter (ending January 2011 and mid-spring (ending May 2011 under pine trees and in bare soil. The soil samples were used to evaluate soil physicochemical properties and soil microbial

  17. An integrated model of environmental effects on growth, carbohydrate balance, and mortality of Pinus ponderosa forests in the southern Rocky Mountains.

    Directory of Open Access Journals (Sweden)

    Christina L Tague

    Full Text Available Climate-induced tree mortality is an increasing concern for forest managers around the world. We used a coupled hydrologic and ecosystem carbon cycling model to assess temperature and precipitation impacts on productivity and survival of ponderosa pine (Pinus ponderosa. Model predictions were evaluated using observations of productivity and survival for three ponderosa pine stands located across an 800 m elevation gradient in the southern Rocky Mountains, USA, during a 10-year period that ended in a severe drought and extensive tree mortality at the lowest elevation site. We demonstrate the utility of a relatively simple representation of declines in non-structural carbohydrate (NSC as an approach for estimating patterns of ponderosa pine vulnerability to drought and the likelihood of survival along an elevation gradient. We assess the sensitivity of simulated net primary production, NSC storage dynamics, and mortality to site climate and soil characteristics as well as uncertainty in the allocation of carbon to the NSC pool. For a fairly wide set of assumptions, the model estimates captured elevational gradients and temporal patterns in growth and biomass. Model results that best predict mortality risk also yield productivity, leaf area, and biomass estimates that are qualitatively consistent with observations across the sites. Using this constrained set of parameters, we found that productivity and likelihood of survival were equally dependent on elevation-driven variation in temperature and precipitation. Our results demonstrate the potential for a coupled hydrology-ecosystem carbon cycling model that includes a simple model of NSC dynamics to predict drought-related mortality. Given that increases in temperature and in the frequency and severity of drought are predicted for a broad range of ponderosa pine and other western North America conifer forest habitats, the model potentially has broad utility for assessing ecosystem vulnerabilities.

  18. An integrated model of environmental effects on growth, carbohydrate balance, and mortality of Pinus ponderosa forests in the southern Rocky Mountains

    Science.gov (United States)

    Tague, Christina L.; McDowell, Nathan G.; Allen, Craig D.

    2013-01-01

    Climate-induced tree mortality is an increasing concern for forest managers around the world. We used a coupled hydrologic and ecosystem carbon cycling model to assess temperature and precipitation impacts on productivity and survival of ponderosa pine (Pinus ponderosa). Model predictions were evaluated using observations of productivity and survival for three ponderosa pine stands located across an 800 m elevation gradient in the southern Rocky Mountains, USA, during a 10-year period that ended in a severe drought and extensive tree mortality at the lowest elevation site. We demonstrate the utility of a relatively simple representation of declines in non-structural carbohydrate (NSC) as an approach for estimating patterns of ponderosa pine vulnerability to drought and the likelihood of survival along an elevation gradient. We assess the sensitivity of simulated net primary production, NSC storage dynamics, and mortality to site climate and soil characteristics as well as uncertainty in the allocation of carbon to the NSC pool. For a fairly wide set of assumptions, the model estimates captured elevational gradients and temporal patterns in growth and biomass. Model results that best predict mortality risk also yield productivity, leaf area, and biomass estimates that are qualitatively consistent with observations across the sites. Using this constrained set of parameters, we found that productivity and likelihood of survival were equally dependent on elevation-driven variation in temperature and precipitation. Our results demonstrate the potential for a coupled hydrology-ecosystem carbon cycling model that includes a simple model of NSC dynamics to predict drought-related mortality. Given that increases in temperature and in the frequency and severity of drought are predicted for a broad range of ponderosa pine and other western North America conifer forest habitats, the model potentially has broad utility for assessing ecosystem vulnerabilities.

  19. An integrated model of environmental effects on growth, carbohydrate balance, and mortality of Pinus ponderosa forests in the southern Rocky Mountains.

    Science.gov (United States)

    Tague, Christina L; McDowell, Nathan G; Allen, Craig D

    2013-01-01

    Climate-induced tree mortality is an increasing concern for forest managers around the world. We used a coupled hydrologic and ecosystem carbon cycling model to assess temperature and precipitation impacts on productivity and survival of ponderosa pine (Pinus ponderosa). Model predictions were evaluated using observations of productivity and survival for three ponderosa pine stands located across an 800 m elevation gradient in the southern Rocky Mountains, USA, during a 10-year period that ended in a severe drought and extensive tree mortality at the lowest elevation site. We demonstrate the utility of a relatively simple representation of declines in non-structural carbohydrate (NSC) as an approach for estimating patterns of ponderosa pine vulnerability to drought and the likelihood of survival along an elevation gradient. We assess the sensitivity of simulated net primary production, NSC storage dynamics, and mortality to site climate and soil characteristics as well as uncertainty in the allocation of carbon to the NSC pool. For a fairly wide set of assumptions, the model estimates captured elevational gradients and temporal patterns in growth and biomass. Model results that best predict mortality risk also yield productivity, leaf area, and biomass estimates that are qualitatively consistent with observations across the sites. Using this constrained set of parameters, we found that productivity and likelihood of survival were equally dependent on elevation-driven variation in temperature and precipitation. Our results demonstrate the potential for a coupled hydrology-ecosystem carbon cycling model that includes a simple model of NSC dynamics to predict drought-related mortality. Given that increases in temperature and in the frequency and severity of drought are predicted for a broad range of ponderosa pine and other western North America conifer forest habitats, the model potentially has broad utility for assessing ecosystem vulnerabilities.

  20. Alternative Parameterization of the 3-PG Model for Loblolly Pine: A Regional Validation and Climate Change Assessment on Stand Productivity

    Science.gov (United States)

    Yang, J.; Gonzalez-Benecke, C. A.; Teskey, R. O.; Martin, T.; Jokela, E. J.

    2015-12-01

    Loblolly pine (Pinus taeda L.) is one of the fastest growing pine species. It has been planted on more than 10 million ha in the southeastern U.S., and also been introduced into many countries. Using data from the literature and long-term productivity studies, we re-parameterized the 3-PG model for loblolly pine stands. We developed new functions for estimating NPP allocation dynamics, canopy cover and needlefall dynamics, effects of frost on production, density-independent and density-dependent tree mortality, biomass pools at variable starting ages, and the fertility rating. New functions to estimate merchantable volume partitioning were also included, allowing for economic analyses. The fertility rating was determined as a function of site index (mean height of dominant trees at age=25 years). We used the largest and most geographically extensive validation dataset for this species ever used (91 pots in 12 states in U.S. and 10 plots in Uruguay). Comparison of modeled to measured data showed robust agreement across the natural range in the U.S., as well as in Uruguay, where the species is grown as an exotic. Using the new set of functions and parameters with downscaled projections from twenty different climate models, the model was applied to assess the impact of future climate change scenarios on stand productivity in the southeastern U.S.

  1. Economic significance of noxious insects in pine stands under the permanent impact of the industrial air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Sierpinski, Z

    1970-01-01

    Studies revealed that numerous species of noxious insects, particularly those from the group of so-called harassing and secondary pests, found favorable conditions for their development in areas under permanent impact of industrial air pollution. The most numerous and most important species in pine stands is Exoteleia dodecella L., the larvae of which at first mine needles, then destroy the buds. Feeding by this pest causes deformations as a result of which younger trees acquire a shrubby form, while older ones are umbrella-shaped. Among the primary pests, Acantholyda nemoralis Thoms. and sometimes Lymantria monacha L., may occur more abundantly in the areas containing little industrial emissions. In older stands secondary pests which could be divided into two groups were of great economic importance. The first group includes Phaenops cyanea F., Pissodes piniphilus Hbst., and Paururus juvencus L. which infest trees in gappy stands, strongly thinned ones, and those adjoining industrial plants.

  2. Effects of Initial Stand Density and Climate on Red Pine Productivity within Huron National Forest, Michigan, USA

    Directory of Open Access Journals (Sweden)

    Joseph O'Brien

    2012-12-01

    Full Text Available Changes in climate are predicted to significantly affect the productivity of trees in the Great Lakes region over the next century. Forest management decisions, such as initial stand density, can promote climatic resiliency and moderate decreased productivity through the reduction of tree competition. The influences of climate (temperature and precipitation and forest management (initial stand density on the productivity of red pine (Pinus resinosa across multiple sites within Huron National Forest, Michigan, were examined using dendrochronological methods. Two common planting regimes were compared in this analysis; low initial density (1977 trees per hectare. Low initial density stands were found to have a higher climatic resilience by combining equal or greater measures of productivity, while having a reduced sensitivity to monthly and seasonal climate, particularly to summer drought.

  3. Structure and Composition of Vegetation of Longleaf Pine Plantations Compared to Natural Stands Occurring Along an Environmental Gradient at the Savannah River Site

    Science.gov (United States)

    Gregory P. Smith; Victor B. Shelburne; Joan L. Walker

    2002-01-01

    Fifty-four plots in 33-43 year old longleaf pine plantations were compared to 30 remnant plots in longleaf stands on the Savannah River Site in South Carolina. Within these stands, the structure and composition of primarily the herb layer relative to a presumed soil moisture or soil texture gradient was studied using the North Carolina Vegetation Survey methodology....

  4. A multivariate mixed model system for wood specific gravity and moisture content of planted loblolly pine stands in the southern United States

    Science.gov (United States)

    Finto Antony; Laurence R. Schimleck; Alex Clark; Richard F. Daniels

    2012-01-01

    Specific gravity (SG) and moisture content (MC) both have a strong influence on the quantity and quality of wood fiber. We proposed a multivariate mixed model system to model the two properties simultaneously. Disk SG and MC at different height levels were measured from 3 trees in 135 stands across the natural range of loblolly pine and the stand level values were used...

  5. Post-fire plant diversity and abundance in pine and eucalypt stands in Portugal : Effects of biogeography, topography, forest type and post-fire management

    NARCIS (Netherlands)

    Maia, P.; Keizer, J.; Vasques, A.; Abrantes, N.; Roxo, L.; Fernandes, P.; Ferreira, A.; Moreira, F.

    2014-01-01

    This study concerned the mid-term regeneration of the woody understory vegetation of pure and mixed stands of Pinus pinaster Ait. and Eucalyptus globulus Labill. in northern and central Portugal following wildfires in 2005 and 2006. Pine and eucalypt stands are the most widespread and most

  6. Survey of foliar monoterpenes across the range of jack pine reveal three widespread chemotypes: implications to host expansion of invasive mountain pine beetle

    Directory of Open Access Journals (Sweden)

    Spencer eTaft

    2015-05-01

    Full Text Available The secondary compounds of pines (Pinus can strongly affect the physiology, ecology and behaviors of the bark beetles (Coleoptera: Curculionidae, Scolytinae that feed on sub-cortical tissues of hosts. Jack pine (Pinus banksiana has a wide natural distribution range in North America (Canada and USA and thus variations in its secondary compounds, particularly monoterpenes, could affect the host expansion of invasive mountain pine beetle (Dendroctonus ponderosae, which has recently expanded its range into the novel jack pine boreal forest. We investigated monoterpene composition of 601 jack pine trees from natural and provenance forest stands representing 63 populations from Alberta to the Atlantic coast. Throughout its range, jack pine exhibited three chemotypes characterized by high proportions of α-pinene, β-pinene, or limonene. The frequency with which the α-pinene and β-pinene chemotypes occurred at individual sites was correlated to climatic variables, such as continentality and mean annual precipitation, as were the individual α-pinene and β-pinene concentrations. However, other monoterpenes were generally not correlated to climatic variables or geographic distribution. Finally, while the enantiomeric ratios of β-pinene and limonene remained constant across jack pine’s distribution, (‒:(+-α-pinene exhibited two separate trends, thereby delineating two α-pinene phenotypes, both of which occurred across jack pine’s range. These significant variations in jack pine monoterpene composition may have cascading effects on the continued eastward spread and success of D. ponderosae in the Canadian boreal forest.

  7. Diesel fuel oil for increasing mountain pine beetle mortality in felled logs

    Science.gov (United States)

    S. A. Mata; J. M. Schmid; D. A. Leatherman

    2002-01-01

    Diesel fuel oil was applied to mountain pine beetle (Dendroctonus ponderosae Hopkins) infested bolts of ponderosa pine (Pinus ponderosa Lawson) in early June. Just prior to the fuel oil application and 6 weeks later, 0.5 ft2 bark samples were removed from each bolt and the numbers of live beetles counted....

  8. Diet of southern toads (Bufo terrestris) in loblolly pine (Pinus taeda) stands subject to coarse woody debris manipulations.

    Energy Technology Data Exchange (ETDEWEB)

    Moseley, Kurtis R.; Steven B. Castleberry; James L. Hanula; Mark Ford.

    2005-04-01

    ABSTRACT In the southeastern United States, coarse woody debris (CWD) typically harbors high densities of invertebrates. However, its importance as a foraging substrate for southeastern amphibians is relatively unknown. We examined effects of CWD manipulations on diet composition of southern toads (Bufo terrestris) in upland loblolly pine (Pinus taeda) stands in the Coastal Plain of South Carolina. Twelve 9.3-ha plots were assigned one of the following treatments: removal- all CWD _10 cm in diameter and _60 cm long removed; downed- five-fold increase in volume of down CWD; and unmanipulated control stands. We collected southern toads _4 cm snout-vent length (SVL) during 14 d sampling periods in June and October 2002, June 2003 and during a 28 d sampling period in April 2003. We collected 80, 36 and 35 southern toads in control, downed and removal treatments, respectively. We found no difference in relative abundance or frequency of invertebrate groups consumed among treatments (P.0.05). Average body weight (g), SVL (cm) and stomach content weight (g wet) of individuals also were similar among treatments (P . 0.05). The role of CWD as a foraging substrate for southern toads in loblolly pine stands of the southeastern Coastal Plain may be negligible, at least in the early stages of decay.

  9. Variability of sun-induced chlorophyll fluorescence according to stand age-related processes in a managed loblolly pine forest.

    Science.gov (United States)

    Colombo, Roberto; Celesti, Marco; Bianchi, Remo; Campbell, Petya K E; Cogliati, Sergio; Cook, Bruce D; Corp, Lawrence A; Damm, Alexander; Domec, Jean-Christophe; Guanter, Luis; Julitta, Tommaso; Middleton, Elizabeth M; Noormets, Asko; Panigada, Cinzia; Pinto, Francisco; Rascher, Uwe; Rossini, Micol; Schickling, Anke

    2018-02-20

    Leaf fluorescence can be used to track plant development and stress, and is considered the most direct measurement of photosynthetic activity available from remote sensing techniques. Red and far-red sun-induced chlorophyll fluorescence (SIF) maps were generated from high spatial resolution images collected with the HyPlant airborne spectrometer over even-aged loblolly pine plantations in North Carolina (United States). Canopy fluorescence yield (i.e., the fluorescence flux normalized by the light absorbed) in the red and far-red peaks was computed. This quantifies the fluorescence emission efficiencies that are more directly linked to canopy function compared to SIF radiances. Fluorescence fluxes and yields were investigated in relation to tree age to infer new insights on the potential of those measurements in better describing ecosystem processes. The results showed that red fluorescence yield varies with stand age. Young stands exhibited a nearly twofold higher red fluorescence yield than mature forest plantations, while the far-red fluorescence yield remained constant. We interpreted this finding in a context of photosynthetic stomatal limitation in aging loblolly pine stands. Current and future satellite missions provide global datasets of SIF at coarse spatial resolution, resulting in intrapixel mixture effects, which could be a confounding factor for fluorescence signal interpretation. To mitigate this effect, we propose a surrogate of the fluorescence yield, namely the Canopy Cover Fluorescence Index (CCFI) that accounts for the spatial variability in canopy structure by exploiting the vegetation fractional cover. It was found that spatial aggregation tended to mask the effective relationships, while the CCFI was still able to maintain this link. This study is a first attempt in interpreting the fluorescence variability in aging forest stands and it may open new perspectives in understanding long-term forest dynamics in response to future climatic

  10. Limber pine forests on the leading edge of white pine blister rust distribution in Northern Colorado

    Science.gov (United States)

    Jennifer G. Klutsch; Betsy A. Goodrich; Anna W. Schoettle

    2011-01-01

    The combined threats of the current mountain pine beetle (Dendroctonus ponderosae, MPB) epidemic with the imminent invasion of white pine blister rust (caused by the non-native fungus Cronartium ribicola, WPBR) in limber pine (Pinus flexilis) forests in northern Colorado threatens the limber pine's regeneration cycle and ecosystem function. Over one million...

  11. 76 FR 48120 - Black Hills National Forest, Custer, SD-Mountain Pine Beetle Response Project

    Science.gov (United States)

    2011-08-08

    ... species on lands of all ownerships in the Black Hills is ponderosa pine (Pinus ponderosae). Since 1997 the... rated as having high wildfire hazard. Since 1980, due to several factors including drought the Forest...

  12. Analysis of energy wood supply chain in thinning operations: a case study in a pine stand of Central Italy

    Directory of Open Access Journals (Sweden)

    Baldini S

    2010-10-01

    Full Text Available Thinning is an essential practice in Mediterranean pine forests management but is rarely applied because of the high harvesting costs. The new market of bioenergy products could give a profit to wood biomass harvesting activities, though the drawbacks of elevated supply chain costs, related to technical problems and lack of knowledge about the wood quality have to be overcome in advance. This study analyzed technical, economic, energy and environmental factors of a pine stand thinning in Central Italy, where collected biomass was directed to energy, in order to give a decisional support to reach economical profitability and environmental sustainability in thinning practices. The introduction of Full Tree System maximized the recovery of available biomass, full tree chipping produced material with Heating Value superior than single tree components. The use of a felling frame in motor-manual felling in comparison with the traditional chainsaw reduced operator effort, increasing the number of felled trees per hour, when the stump diameter remained under 15 cm. The energy wood supply chain is not sustainable from an economic point of view, the profitability could be reached only acting on suggested technical levers and particularly reducing costs of hauling operation. The estimation of output/input energy ratio in the supply chain underlined the feasibility of thinning practices for energy. The assessment of CO2 emissions confirmed the environmental sustainability of biomass supply chain in energy when compared to traditional fossil fuels. Study conclusions provide the guidelines for thinning treatment in Mediterranean pine stands, in order to reach environmental and economic sustainability of these practices.

  13. Point processes statistics of stable isotopes: analysing water uptake patterns in a mixed stand of Aleppo pine and Holm oak

    Directory of Open Access Journals (Sweden)

    Carles Comas

    2015-04-01

    Full Text Available Aim of study: Understanding inter- and intra-specific competition for water is crucial in drought-prone environments. However, little is known about the spatial interdependencies for water uptake among individuals in mixed stands. The aim of this work was to compare water uptake patterns during a drought episode in two common Mediterranean tree species, Quercus ilex L. and Pinus halepensis Mill., using the isotope composition of xylem water (δ18O, δ2H as hydrological marker. Area of study: The study was performed in a mixed stand, sampling a total of 33 oaks and 78 pines (plot area= 888 m2. We tested the hypothesis that both species uptake water differentially along the soil profile, thus showing different levels of tree-to-tree interdependency, depending on whether neighbouring trees belong to one species or the other. Material and Methods: We used pair-correlation functions to study intra-specific point-tree configurations and the bivariate pair correlation function to analyse the inter-specific spatial configuration. Moreover, the isotopic composition of xylem water was analysed as a mark point pattern. Main results: Values for Q. ilex (δ18O = –5.3 ± 0.2‰, δ2H = –54.3 ± 0.7‰ were significantly lower than for P. halepensis (δ18O = –1.2 ± 0.2‰, δ2H = –25.1 ± 0.8‰, pointing to a greater contribution of deeper soil layers for water uptake by Q. ilex. Research highlights: Point-process analyses revealed spatial intra-specific dependencies among neighbouring pines, showing neither oak-oak nor oak-pine interactions. This supports niche segregation for water uptake between the two species.

  14. Pines

    Science.gov (United States)

    C. Plomion; D. Chagne; D. Pot; S. Kumar; P.L. Wilcox; R.D. Burdon; D. Prat; D.G. Peterson; J. Paiva; P. Chaumeil; G.G. Vendramin; F. Sebastiani; C.D. Nelson; C.S. Echt; O. Savolainen; T.L. Kubisiak; M.T. Cervera; N. de Maria; M.N. Islam-Faridi

    2007-01-01

    Pinus is the most important genus within the Family Pinaceae and also within the gymnosperms by the number of species (109 species recognized by Farjon 2001) and by its contribution to forest ecosystems. All pine species are evergreen trees or shrubs. They are widely distributed in the northern hemisphere, from tropical areas to northern areas in America and Eurasia....

  15. Emissions of BVOC from lodgepole pine in response to mountain pine beetle attack in high and low mortality forest stands

    Directory of Open Access Journals (Sweden)

    T. R. Duhl

    2013-01-01

    Full Text Available In this screening study, biogenic volatile organic compound (BVOC emissions from intact branches of lodgepole pine (Pinus contorta trees were measured from trees at two forested sites that have been impacted differently by the mountain pine beetle (MPB, with one having higher mortality and the other with lower mortality. Differences in the amounts and chemical diversity of BVOC between the two sites and from apparently healthy trees versus trees in different stages of MPB attack are presented, as well as (for one site observed seasonal variability in emissions. A brief comparison is made of geological and climatic characteristics as well as prior disturbances (both natural and man-made at each site. Trees sampled at the site experiencing high MPB-related tree mortality had lower chemodiversity in terms of monoterpene (MT emission profiles, while profiles were more diverse at the lower-mortality site. Also at the higher-mortality site, MPB-infested trees in various stages of decline had lower emissions of sesquiterpenes (SQTs compared to healthy trees, while at the site with lower mortality, MPB-survivors had significantly higher SQT emissions during part of the growing season when compared to both uninfested and newly infested trees. SQT profiles differed between the two sites and, like monoterpene and oxygenated VOC profiles, varied through the season. For the low-mortality site in which repeated measurements were made over the course of the early summer–late fall, higher chemical diversity was observed in early- compared to late-season measurements for all compound classes investigated (MT, oxygenated VOC, and SQT, with the amount of change appearing to correlate to the MPB status of the trees studied. Emissions of 2-methyl-3-buten-2-ol (MBO had a distinct seasonal signal but were not much different between healthy or infested trees, except in trees with dead needles, from which emissions of this compound were negligible, and in late

  16. Trace gas emissions from a chronosequence of bark beetle-infested lodgepole pine (Pinus contorta) forest stands

    Science.gov (United States)

    Norton, U.; Pendall, E.; Ewers, B. E.; Borkhuu, B.

    2011-12-01

    Severe outbreak of mountain pine beetle (MPB) and associated blue stain fungi have killed millions of hectares of coniferous forests in Western North America. This unprecedented disturbance has critically impacted ecosystem biogeochemistry and net carbon (C) and nitrogen (N) fluxes. However, the effects on greenhouse gas (GHG) emissions and drivers of biogeochemical processes that trigger GHG emissions following MPB infestations are not well understood. Such information can help assess regional-level changes in ecosystem C and N budgets and large-scale disturbance impacts on gas exchange between the atmosphere and terrestrial ecosystem. The overall objective of this research was to assess the immediate responses of GHG fluxes and soil C and N mineralization rates along a chronosequence of recently infested (1-yr, 3-yr and 4-yr ago) and uninfested (150-yr, 20-yr and 15-yr old) lodgepole pine stands in Medicine Bow National Forest in southeastern Wyoming. We hypothesize that MPB-induced tree mortality significantly changes stand-level hydrology, soil organic matter quality and chemistry of aboveground and belowground plant inputs. Consequently, these modifications influence nitrous oxide (N2O) emissions and methane (CH4) assimilation. Biweekly GHG measurements using static chambers were carried out during three consecutive snow-free growing seasons. Our results suggest that a stand infested within a year already shows a 20% increase in spring N2O production and a small decline in summer CH4 assimilation when compared to uninfested stands. Stands infested three and four years prior to our measurements produce over three times more N2O and assimilate three to five times less CH4 when compared to uninfested stands. In addition, a notable increase in soil moisture content and soil mineral N concentrations following early onset of the MPB infestation was also observed. An overall increase in N2O production and decline in CH4 assimilation following MPB infestation may

  17. Influence of mountain pine beetle epidemic on winter habitat conditions for Merriam's turkeys: Management implications for current and future condition

    Science.gov (United States)

    Chadwick P. Lehman; Mark A. Rumble; Michael A. Battaglia; Todd R. Mills; Lance A. Asherin

    2016-01-01

    Understanding response of ponderosa pine (Pinus ponderosa) forest development following a mountain pine beetle (MPB; Dendroctonus ponderosae) epidemic has important management implications for winter habitat conditions for Merriam’s wild turkeys (Meleagris gallopavo merriami; hereafter, turkeys). Therefore, we quantified habitat changes over time for turkeys...

  18. Stand conditions immediately following a restoration harvest in an old-growth pine-hardwood remnant

    Science.gov (United States)

    D. C. Bragg

    2010-01-01

    Portions of the Levi Wilcoxon Demonstration Forest (LWDF), a privately owned parcel of old-growth pine and hardwoods in Ashley County, Arkansas, were recently treated to restore conditions similar to some historic accounts of the virgin forest. Following a hardwood-only cut, a post-harvest inventory showed that the number of tree species in the sample area declined...

  19. Performance of mixed pine-hardwood stands 16 years after fell-and-burn treatments

    Science.gov (United States)

    Elizabeth M. Blizzard; David H. van Lear; G. Geoff Wang; Thomas A. Waldrop

    2006-01-01

    Four variations of the fell-and-burn technique were compared for height and volume production on dry Piedmont sites. A two-factorial randomized complete block design of winter versus spring felling, with and without a summer burn, was implemented, followed by planting of loblolly pine (Pinus taeda L.) at 15 x 15 foot spacing. After 16 growing seasons...

  20. Cogongrass ( Imperata cylindrica ) affects above- and belowground processes in commercial loblolly pine ( Pinus taeda ) stands

    Science.gov (United States)

    Adam N. Trautwig; Lori G. Eckhardt; Nancy J. Loewenstein; Jason D. Hoeksema; Emily A. Carter; Ryan L. Nadel

    2017-01-01

    Cogongrass (Imperata cylindrica), an invasive grass species native to Asia, has been shown to reduce tree vigor in loblolly pine (Pinus taeda) plantations, which comprise more than 50% of growing stock in commercial forests of the United States. I. cylindrica produces exudates with possible allelopathic effects that may influence abundance of P. taeda symbionts, such...

  1. Post-fire diversity and abundance in pine and eucalipt stands in Portugal: effects of biogeography, topography, forest type and post-fire management

    OpenAIRE

    Maia, P.; Keizer, J.; Vasques, A.; Abrantes, N.; Roxo, L.; Fernandes, P.; Ferreira, A.; Moreira, F.

    2014-01-01

    This study concerned the mid-term regeneration of the woody understory vegetation of pure and mixed stands of Pinus pinaster Ait. and Eucalyptus globulus Labill. in northern and central Portugal following wildfires in 2005 and 2006. Pine and eucalypt stands are the most widespread and most fire-prone forest types in Portugal. The main aim was to investigate the importance of biogeography, topography, forest type and post-fire management operations in explaining the patterns in shr...

  2. Xylem monoterpenes of some hard pines of Western North America: three studies

    Science.gov (United States)

    Richard H. Smith

    1982-01-01

    Monoterpene composition was studied in a number of hard pine species and results were compared with earlier work. (1) Intratree measurements showed strong constancy of composition in both single-stemmed and forked trees of ponderosa, Jeffrey, Coulter, and Jeffrey x ponderosa pines. In grafts of these and other pines, the scion influenced the root stock, but not the...

  3. FlorNExT®, a cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait. stands in Northeastern Portugal

    Directory of Open Access Journals (Sweden)

    Fernando Pérez-Rodríguez

    2016-07-01

    Full Text Available Aim of the study: To introduce and describe FlorNExT®, a free cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait. even-aged stands in the Northeast of Portugal (NE Portugal. Area of study: NE Portugal. Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves and basal area, as well as output functions for tree and stand volume, biomass, and carbon content. Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/. Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal. Keywords: forest management; maritime pine; forest modelling; knowledge transfer tool.

  4. Grazing on Regeneration Sites Encourages Pine Seedling Growth

    Science.gov (United States)

    Raymond D. Ratliff; Renee G. Denton

    1995-01-01

    Effects of season-long, deferred-rotation, and rest-rotation grazing, on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedling growth and herbaceous vegetation control were studied in regeneration sites at Boyd Hill, Modoc National Forest, California. Seedlings were planted in 1989. Pine seedling survival and damage did not differ, but the...

  5. A Linked Model for Simulating Stand Development and Growth Processes of Loblolly Pine

    Science.gov (United States)

    V. Clark Baldwin; Phillip M. Dougherty; Harold E. Burkhart

    1998-01-01

    Linking models of different scales (e.g., process, tree-stand-ecosystem) is essential for furthering our understanding of stand, climatic, and edaphic effects on tree growth and forest productivity. Moreover, linking existing models that differ in scale and levels of resolution quickly identifies knowledge gaps in information required to scale from one level to another...

  6. Site establishment practices influence loblolly pine mortality throughout the stand rotation

    Science.gov (United States)

    Felipe G. Sanchez; Robert J. Eaton

    2010-01-01

    During a rotation, land managers need to estimate yields, update inventories, and evaluate stand dynamics. All of these factors in land management are heavily influenced by tree mortality. Tree mortality can, in turn, be influenced by land management practices from the inception of the stand and throughout the rotation. We describe the impact of organic matter removal...

  7. Sixth-Year Results Following Partial Cutting For Timber and Wildlife Habitat in a Mixed Oak-Sweetgum-Pine Stand on a Minor Creek Terrace in Southeast Louisiana

    Science.gov (United States)

    Brian Roy Lockhart; Norwin E. Linnartz

    2002-01-01

    Hardwood management has primarily focused on highly productive river bottom and upland sites. Less is known about hardwood growth and development on terrace sites. Such sites are usually converted to other uses, especially pine plantations. The objectives of this study, implemented in a minor creek terrace in southeast Louisiana, were to describe changes in stand...

  8. Forest attributes and fuel loads of riparian vs. upland stands in mountain pine beetle infested watersheds, southern Rocky Mountains [Chapter 13

    Science.gov (United States)

    Kathleen A. Dwire; Roberto A. Bazan; Robert Hubbard

    2015-01-01

    Extensive outbreaks of mountain pine beetle (MPB), spruce beetle (SB), and other insects are altering forest stand structure throughout the Western United States, and thereby increasing the natural heterogeneity of fuel distribution. Riparian forests frequently occur as narrow linear features in the landscape mosaic and can contribute to the spatial complexity of...

  9. Distribution and migration of cesium and strontium radionuclides in Estonian scots pine stands

    International Nuclear Information System (INIS)

    Martin, L.; Tekko, S.; Aaspollu, J.; Martin, J.; Vilde, R.; Nifontova, M.

    1994-01-01

    Radioactive pollution from the Chernobyl NPS reactor accident in 1986 has wide scale impact through radionuclides fallout over large areas. We used mushrooms, macrolichenes, mosses and pine needles, forest litter and soil for the investigaton of 137 Cs and 90 Sr accumulation and migration in pine ecosystems. Systematic collections were made on 63 field sites, total amount of samples analyzed is 350. Highest concentrations of radiocaesium were determined in mushrooms (41.8 kBq/kg) in north-east of Estonia, in macrolichens at the Lahemaa National Park (6.2 kBq/kg). At the Rumpo Botanical Reserve the level of radiocaesium exceeded background concentration (1985) 1.3-1.8 times and at the Koljaku 4.0-4.4 times. During five years of observations (1986-1991) decrease of radionuclides pollution revealed 15 times the Rumpo and Koljaku. Radiostrontium concentrations in different ecosystem compartments all over the territory did not exeed harmful levels. (author). 2 tabs

  10. 137Cs accumulation in components of pine stands in Polessye of Ukraine

    International Nuclear Information System (INIS)

    Krasnov, V.P.; Orlov, A.A.; Gusarevich, M.G.

    2005-01-01

    Distribution of 137 Cs specific activity in structural components of Scotch pine in different parts of crone and tree trunk (according the height) was analyzed; the average value 137 Cs transfer factor (TF) for all investigated components was calculated. Decreasing of 137 Cs specific activity and values of TF from upper crone part through middle to the lowest one has been shown for the majority pine crone components in edatops B 2 and B 3 . It was drown a calculation that 137 Cs specific activities and TF values stably decreased in tree trunk components from upper part through middle to the lowest one in edatop B 3 . In edatop B 2 decreasing of 137 Cs specific activity and TF values for external and internal bark was also revealed in the same direction. The decreasing of 137 Cs specific activity and TF values for wood was revealed from upper part of the trunk to middle one and their increasing to the lowest tree trunk part. It was shown that physiologically active organs and tissues in the pine are characterized by the maximum accumulation: one-year-o;d shoots, one-year-old needles, internal bark. It was drown an important conclusion that part of tree trunk (according to its height), which used as fuel wood and construction materials, is a strong modification factor of 137 Cs content in complete product and this fact should be taken into account for forest cutting activities. (author)

  11. Soil carbon and nitrogen budget in Scots pine (Pinus sylvestris L.) stands along an air pollution gradient in eastern Germany

    International Nuclear Information System (INIS)

    Fischer, T.; Bergmann, C.; Huettl, R.F.

    1995-01-01

    Litterfall, bio- and necromass of the forest floor vegetation, decomposition of recent organic material, soil respiration and humus stocks were examined in 3 Scots pine stands along an air pollution gradient in eastern Germany. One site, Rosea, received heavy deposition loads from chemical industries and brown coal fired power plants. The site Taura received moderate air pollution due to lower deposition of coarse and calcium rich dust particles; the third site, Neuglobsow was afforested and represents a low polluted control site. High nitrogen loads and increased pH value due to Ca deposition caused shifts in the vegetation structure, and higher biomass production of the forest floor vegetation, whereas needle litter production was not impacted. Simultaneously, decomposition rates of the recently harvested forest floor vegetation decreased with increasing pollutant loads, but needle litter and soil organic matter decomposition rates did not differ between the sites. Consequently, soil carbon and nitrogen stocks increased with increasing pollutant input. 19 refs., 5 figs., 1 tab

  12. Effect of coarse woody debris manipulation on soricid and herpetofaunal communities in upland pine stands of the southeastern coastal plain.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Justin, Charles

    2009-04-01

    Abstract -The majority of studies investigating the importance of coarse woody debris (CWD) to forest- floor vertebrates have taken place in the Pacific Northwest and southern Appalachian Mountains, while comparative studies in the southeastern Coastal Plain are lacking. My study was a continuation of a long-term project investigating the importance of CWD as a habitat component for shrew and herpetofaunal communities within managed pine stands in the southeastern Coastal Plain. Results suggest that addition of CWD can increase abundance of southeastern and southern short-tailed shrews. However, downed wood does not appear to be a critical habitat component for amphibians and reptiles. Rising petroleum costs and advances in wood utilization technology have resulted in an emerging biofuels market with potential to decrease CWD volumes left in forests following timber harvests. Therefore, forest managers must understand the value of CWD as an ecosystem component to maintain economically productive forests while conserving biological diversity.

  13. Ectomycorrhizal Community Structure and Soil Characteristics of Mature Lodgepole Pine (Pinus Contorta) and Adjacent Stands of Old Growth Mixed Conifer in Yellowstone National Park, Wyoming USA

    Science.gov (United States)

    Douglas, Robert B.; Parker, V. Thomas; Cullings, Kenneth W.; Sun, Sidney (Technical Monitor)

    2003-01-01

    Forest development patterns following disturbance are known to influence the physical and chemical attributes of soils at different points in time. Changes in soil resources are thought to have a corresponding effect on ectomycorrhizal (ECM) community structure. We used molecular methods to compare below-ground ECM species richness, composition, and abundance between adjacent stands of homogenous lodgepole pine and old growth mixed conifer in Yellowstone National Park (YNP). In each stand-type we collected soil cores to both identify mycorrhizae and assess soil chemistry. Although no statistical difference was observed in the mean number of ECM root tips per core between stand types, the total number of species identified (85 versus 35) and the mean number of species per core (8.8 +/- 0.6 versus 2.5 +/- 0.3) were significantly higher in lodgepole pine. Differences between the actual and estimated species richness levels indicated that these forest types support a high number of ECM species and that undersampling was severe. Species compositions were widely disparate between stands where only four species were shared out of a total of 116. Soil analysis also revealed that mixed conifer was significantly lower in pH, but higher in organic matter, potassium, phosphorus, and ammonium when compared to lodgepole pine stands. Species richness per core was correlated with these chemical data, however, analysis of covariance indicated that stand type was the only statistically significant factor in the observed difference in species richness. Our data suggest that ECM fungal richness increases as homogenous lodgepole pine stands grow and mature, but declines after Engelmann spruce and subalpine fir colonize. Despite difficulties linking species composition with soil chemistry, there are a variety of physical and chemical factors that could be influencing ECM community structure. Future field experiments are necessary to test some of the mechanisms potentially operating

  14. Moisture-driven xylogenesis in Pinus ponderosa from a Mojave Desert mountain reveals high phenological plasticity.

    Science.gov (United States)

    Ziaco, Emanuele; Truettner, Charles; Biondi, Franco; Bullock, Sarah

    2018-04-01

    Future seasonal dynamics of wood formation in hyperarid environments are still unclear. Although temperature-driven extension of the growing season and increased forest productivity are expected for boreal and temperate biomes under global warming, a similar trend remains questionable in water-limited regions. We monitored cambial activity in a montane stand of ponderosa pine (Pinus ponderosa) from the Mojave Desert for 2 consecutive years (2015-2016) showing opposite-sign anomalies between warm- and cold-season precipitation. After the wet winter/spring of 2016, xylogenesis started 2 months earlier compared to 2015, characterized by abundant monsoonal (July-August) rainfall and hyperarid spring. Tree size did not influence the onset and ending of wood formation, highlighting a predominant climatic control over xylem phenological processes. Moisture conditions in the previous month, in particular soil water content and dew point, were the main drivers of cambial phenology. Latewood formation started roughly at the same time in both years; however, monsoonal precipitation triggered the formation of more false rings and density fluctuations in 2015. Because of uncertainties in future precipitation patterns simulated by global change models for the Southwestern United States, the dependency of P. ponderosa on seasonal moisture implies a greater conservation challenge than for species that respond mostly to temperature conditions. © 2018 John Wiley & Sons Ltd.

  15. Disentangling the climate-driven bimodal growth pattern in coastal and continental Mediterranean pine stands.

    Science.gov (United States)

    Pacheco, Arturo; Camarero, J Julio; Ribas, Montse; Gazol, Antonio; Gutierrez, E; Carrer, Marco

    2018-02-15

    Mediterranean climate promotes two distinct growth peaks separated by summer quiescence in trees. This bimodal pattern has been associated to favourable growing conditions during spring and autumn when mild temperatures and soil-water availability enhance cambial activity. Climatic models predict progressive warming and drying for the Mediterranean Basin, which could shorten or shift the spring and autumn growing seasons. We explored this idea by comparing two sites with different Mediterranean climate types (continental/dry and coastal/wet) and studied how climate drives the bimodal growth pattern in Aleppo pine (Pinus halepensis). Specifically we investigated the intra-annual changes in wood anatomy and the corresponding formation of density fluctuations (IADF). Trees on both sites were analyzed by dendrometer monitoring and by developing chronologies of wood anatomical traits. Radial-increment dynamics followed a similar bimodal pattern in both sites but coastal trees showed higher increments during the spring and autumn growth peaks, especially in autumn. The summer rest of cambium activity occurs almost one month earlier in the coastal than in the inland site. Lumen area and cell-wall thickness were significantly smaller in the continental site, while the increment rate of cell-wall thickness during an IADF event was much higher in the coastal pines. The accumulated soil moisture deficit was the main climatic constraint of tracheid enlargement in continental pines. Intra-annual density fluctuations were more frequent in the coastal trees where wood anatomy features recover to average values after such events, meanwhile inland trees presented a much lower recovery rate. Growth bimodality and the formation of density fluctuations were linked, but mild climate of the coastal site allows a longer growing season, which explains why trees in this area showed higher and more variable growth rates. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. The evaluation of different forest structural indices to predict the stand aboveground biomass of even-aged Scotch pine (Pinus sylvestris L.) forests in Kunduz, Northern Turkey.

    Science.gov (United States)

    Ercanli, İlker; Kahriman, Aydın

    2015-03-01

    We assessed the effect of stand structural diversity, including the Shannon, improved Shannon, Simpson, McIntosh, Margelef, and Berger-Parker indices, on stand aboveground biomass (AGB) and developed statistical prediction models for the stand AGB values, including stand structural diversity indices and some stand attributes. The AGB prediction model, including only stand attributes, accounted for 85 % of the total variance in AGB (R (2)) with an Akaike's information criterion (AIC) of 807.2407, Bayesian information criterion (BIC) of 809.5397, Schwarz Bayesian criterion (SBC) of 818.0426, and root mean square error (RMSE) of 38.529 Mg. After inclusion of the stand structural diversity into the model structure, considerable improvement was observed in statistical accuracy, including 97.5 % of the total variance in AGB, with an AIC of 614.1819, BIC of 617.1242, SBC of 633.0853, and RMSE of 15.8153 Mg. The predictive fitting results indicate that some indices describing the stand structural diversity can be employed as significant independent variables to predict the AGB production of the Scotch pine stand. Further, including the stand diversity indices in the AGB prediction model with the stand attributes provided important predictive contributions in estimating the total variance in AGB.

  17. Interception loss, throughfall and stemflow in a maritime pine stand. II. An application of Gash's analytical model of interception

    Science.gov (United States)

    Loustau, D.; Berbigier, P.; Granier, A.

    1992-10-01

    Interception, throughfall and stemflow were determined in an 18-year-old maritime pine stand for a period of 30 months. This involved 71 rainfall events, each corresponding either to a single storm or to several storms. Gash's analytical model of interception was used to estimate the sensitivity of interception to canopy structure and climatic parameters. The seasonal cumulative interception loss corresponded to 12.6-21.0% of the amount of rainfall, whereas throughfall and stemflow accounted for 77-83% and 1-6%, respectively. On a seasonal basis, simulated data fitted the measured data satisfactorily ( r2 = 0.75). The rainfall partitioning between interception, throughfall and stemflow was shown to be sensitive to (1) the rainfall regime, i.e. the relative importance of light storms to total rainfall, (2) the climatic parameters, rainfall rate and average evaporation rate during storms, and (3) the canopy structure parameters of the model. The low interception rate of the canopy was attributed primarily to the low leaf area index of the stand.

  18. Gap fraction based estimation of LAI in Scots pine stands subjected to experimental removal of branches and stems

    International Nuclear Information System (INIS)

    Stenberg, P.; Nilson, T.; Smolander, H.; Voipio, P.

    2003-01-01

    We compared estimates of leaf area index obtained by the LAI-2000 plant canopy analyzer (LAI PCA ) to direct estimates of LAI ('true' LAI) obtained through allometric relationships. This was done for two Scots pine (Pinus sylvestris L.) stands, where LAI was gradually reduced by removing branches and whole trees. LAI (defined on a hemisurface area basis) decreased from 2.24 to 0.50 in the branch removal experiment and from 1.58 to 0.29 in the tree removal experiment. The aim of the study was to analyse the variation in the ratio of the LAI-2000 estimate to the true LAI (LAI PCA /LAI) with changes in stand structure and total leaf area. In the tree removal plot, which had a smaller proportion of woody (branch) area, LAI PCA /LAI remained fairly stable (0.63-0.69) and was smaller than that in the branch removal plot, where LAI PCA /LAI increased from 0.76 to 1.16 along with the decrease in leaf area and a subsequent increase in woody (stem) area. The ratio of LAI PCA to the plant area index (PAI) differed less between plots but remained higher in the branch removal plot (increasing from 0.56 to 0.69) than in the tree removal plot, where it varied between 0.55 and 0.60. Results were analysed with the help of a theoretical canopy radiation model, which can be inverted to give LAI based on the gap fraction values measured by the LAI-2000 and stand structural parameters. Model-inverted LAI agreed well with directly measured LAI, suggesting that the model is a useful tool for correcting bias in the LAI-2000 estimates because of grouping of leaf area and the contribution of woody area. (author)

  19. Soil properties and root biomass responses to prescribed burning in young Corsican pine (Pinus nigra Arn.) stands.

    Science.gov (United States)

    Tufekcioglu, Aydin; Kucuk, Mehmet; Saglam, Bulent; Bilgili, Ertugrul; Altun, Lokman

    2010-05-01

    Fire is an important tool in the management of forest ecosystems. Although both prescribed and wildland fires are common in Turkey, few studies have addressed the influence of such disturbances on soil properties and root biomass dynamics. In this study, soil properties and root biomass responses to prescribed fire were investigated in 25-year-old corsican pine (Pinus nigra Arn.) stands in Kastamonu, Turkey. The stands were established by planting and were subjected to prescribed burning in July 2003. Soil respiration rates were determined every two months using soda-lime method over a two-year period. Fine (0-2 mm diameter) and small root (2-5 mm diameter) biomass were sampled approximately bimonthly using sequential coring method. Mean daily soil respiration ranged from 0.65 to 2.19 g Cm(-2) d(-1) among all sites. Soil respiration rates were significantly higher in burned sites than in controls. Soil respiration rates were correlated significantly with soil moisture and soil temperature. Fine root biomass was significantly lower in burned sites than in control sites. Mean fine root biomass values were 4940 kg ha(-1) for burned and 5450 kg ha(-1) for control sites. Soil pH was significantly higher in burned sites than in control sites in 15-35 cm soil depth. Soil organic matter content did not differ significantly between control and burned sites. Our results indicate that, depending on site conditions, fire could be used successfully as a tool in the management of forest stands in the study area.

  20. Biological and Economic Productivity of Mixed-Aged Loblolly Pine Stands in the South

    Science.gov (United States)

    Ronald Raunikar; Joseph Buongiorno; Jeffrey P. Prestemon; Karen Lee-Abt

    1999-01-01

    The financial performance of the 991 sample plots of uneven-aged loblolly-hardwood stands in the Central South FIA database examined in this report depend crucially on real price trends. Equivalent annual income (EAI) is the measure of economic performance. The regional market stumpage price data are from the Timber Mart-South database. For this set of prices, a...

  1. Establishing Pine Monocultures and Mixed Pine-Hardwood Stands on Reclaimed Surface Mined Land in Eastern Kentucky: Implications for Forest Resilience in a Changing Climate

    Directory of Open Access Journals (Sweden)

    Geoffrey Bell

    2017-10-01

    Full Text Available Surface mining and mine reclamation practices have caused significant forest loss and forest fragmentation in Appalachia. Shortleaf pine (Pinus echinata is threatened by a variety of stresses, including diseases, pests, poor management, altered fire regimes, and climate change, and the species is the subject of a widescale restoration effort. Surface mines may present opportunity for shortleaf pine restoration; however, the survival and growth of shortleaf pine on these harsh sites has not been critically evaluated. This paper presents first-year survival and growth of native shortleaf pine planted on a reclaimed surface mine, compared to non-native loblolly pine (Pinus taeda, which has been highly successful in previous mined land reclamation plantings. Pine monoculture plots are also compared to pine-hardwood polyculture plots to evaluate effects of planting mix on tree growth and survival, as well as soil health. Initial survival of shortleaf pine is low (42%, but height growth is similar to that of loblolly pine. No differences in survival or growth were observed between monoculture and polyculture treatments. Additional surveys in coming years will address longer-term growth and survival patterns of these species, as well as changes to relevant soil health endpoints, such as soil carbon.

  2. Monitoring white pine blister rust infection and mortality in whitebark pine in the Greater Yellowstone ecosystem

    Science.gov (United States)

    Cathie Jean; Erin Shanahan; Rob Daley; Gregg DeNitto; Dan Reinhart; Chuck Schwartz

    2011-01-01

    There is a critical need for information on the status and trend of whitebark pine (Pinus albicaulis) in the Greater Yellowstone Ecosystem (GYE). Concerns over the combined effects of white pine blister rust (WPBR, Cronartium ribicola), mountain pine beetle (MPB, Dendroctonus ponderosae), and climate change prompted an interagency working group to design and implement...

  3. Selection for resistance to white pine blister rust affects the abiotic stress tolerances of limber pine

    Science.gov (United States)

    Patrick J. Vogan; Anna W. Schoettle

    2015-01-01

    Limber pine (Pinus flexilis) mortality is increasing across the West as a result of the combined stresses of white pine blister rust (Cronartium ribicola; WPBR), mountain pine beetle (Dendroctonus ponderosae), and dwarf mistletoe (Arceuthobium cyanocarpum) in a changing climate. With the continued spread of WPBR, extensive mortality will continue with strong selection...

  4. Importance of log size on host selection and reproductive success of Ips pini (Coleoptera: Scolytidae) in ponderosa pine slash of northern Arizona and western Montana

    Science.gov (United States)

    Brytten E. Steed; Michael R. Wagner

    2004-01-01

    Pine engraver, Ips pini (Say), often use thinning slash, and their populations are known to be influenced by the condition of this material. In our study, we evaluated the importance of three log diameters (5, 10, and 20 cm) and three lengths (60, 120, and 240 cm) on various parameters of bark beetle host attack, development, and emergence....

  5. FlorNExT®, a cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait.) stands in Northeastern Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Barreiro, S.; Rua, J.; Tomé, M.

    2016-07-01

    Aim of the study. To introduce and describe FlorNExT®, a free cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait.) even-aged stands in the Northeast of Portugal (NE Portugal). Area of study: NE Portugal. Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves) and basal area, as well as output functions for tree and stand volume, biomass, and carbon content. Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/. Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal. (Author)

  6. Individual variation of sap-flow rate in large pine and spruce trees and stand transpiration: a pilot study at the central NOPEX site

    Science.gov (United States)

    Čermák, J.; Cienciala, E.; Kučera, J.; Lindroth, A.; Bednářová, E.

    1995-06-01

    Transpiration in a mixed old stand of sub-boreal forest in the Norunda region (central Sweden) was estimated on the basis of direct measurement of sap flow rate in 24 large Scots pine and Norway spruce trees in July and August 1993. Sap flow rate was measured using the trunk tissue heat balance method based on internal (electric) heating and sensing of temperature. Transpiration was only 0.7 mm day -1 in a relatively dry period in July (i.e. about 20% of potential evaporation) and substantially higher after a rainy period in August. The error of the estimates of transpiration was higher during a dry period (about 13% and 22% in pine and spruce, respectively) and significantly lower (about 9% in both species) during a period of sufficient water supply. Shallow-rooted spruce trees responded much faster to precipitation than deeply rooted pines.

  7. Repeated fire effects on soil physical properties in two young longleaf pine stands on the west gulf coastal plain

    Science.gov (United States)

    Mary Anne Sword Sayer

    2007-01-01

    Repeated prescribed fire is a valuable tool for the management of longleaf and loblolly pine. When applied every two to ten years, for example, prescribed fire perpetuates existing longleaf pine ecosystems (Outcalt 1997). Furthermore, the acceptance of fire as a management tool, together with recent improvements in longleaf pine...

  8. Enhancing Stand Structure through Snag Creation in Northeastern U.S. Forests: Using Ethanol Injections and Bark Beetle Pheromones to Artificially Stress Red Maple and White Pine

    Directory of Open Access Journals (Sweden)

    Kevin J. Dodds

    2016-06-01

    Full Text Available We investigated two methods to create white pine and red maple snags in a forested setting. The first involved injecting trees with ethanol at two times (single Ethanol (ETOH and double ETOH injections to increase attractiveness to insects and elicit attacks on trees. The second method was unique to white pines and involved both injection treatments in combination with baiting trees with Ips-specific pheromones. Three of five white pines from the double ETOH treatment died in the second year. Species including Ips pini (Say, Ips grandicollis Eichhoff, Orthotomicus caelatus Eichhoff, Crypturgus borealis Swaine and Monochamus notatus (Drury responded more strongly to at least one of the treatments over control trees. However, there were no differences found in individual Scolytinae or Cerambycidae species response to treatments in red maple. Fitness (FV/FM and vitality (PIabs were both significantly reduced in both ETOH treatments compared to controls in white pine. In red maple, fitness was reduced in the double ETOH treated trees but the final mean FV/FM values were within the approximate optimal of health. Ethanol injections, in combination with Ips-specific semiochemicals, show promise for creating standing coarse woody debris (CWD in white pine. Injecting ethanol was not effective for stressing red maple.

  9. Effects of stand age and soil properties on soil bacterial and fungal community composition in Chinese pine plantations on the Loess Plateau.

    Directory of Open Access Journals (Sweden)

    Peng Dang

    Full Text Available The effects of Chinese pine (Pinus tabuliformis on soil variables after afforestation have been established, but microbial community changes still need to be explored. Using high-throughput sequencing technology, we analyzed bacterial and fungal community composition and diversity in soils from three stands of different-aged, designated 12-year-old (PF1, 29-year-old (PF2, and 53-year-old (PF3, on a Chinese pine plantation and from a natural secondary forest (NSF stand that was almost 80 years old. Abandoned farmland (BL was also analyzed. Shannon index values of both bacterial and fungal community in PF1 were greater than those in PF2, PF3 and NSF. Proteobacteria had the lowest abundance in BL, and the abundance increased with stand age. The abundance of Actinobacteria was greater in BL and PF1 soils than those in other sites. Among fungal communities, the dominant taxa were Ascomycota in BL and PF1 and Basidiomycota in PF2, PF3 and NSF, which reflected the successional patterns of fungal communities during the development of Chinese pine plantations. Therefore, the diversity and dominant taxa of soil microbial community in stands 12 and 29 years of age appear to have undergone significant changes; afterward, the soil microbial community achieved a relatively stable state. Furthermore, the abundances of the most dominant bacterial and fungal communities correlated significantly with organic C, total N, C:N, available N, and available P, indicating the dependence of these microbes on soil nutrients. Overall, our findings suggest that the large changes in the soil microbial community structure of Chinese pine plantation forests may be attributed to the phyla present (e.g., Proteobacteria, Actinobacteria, Ascomycota and Basidiomycota which were affected by soil carbon and nutrients in the Loess Plateau.

  10. The influence of drought on the water uptake by Scots pines (Pinus sylvestris L. at different positions in the tree stand

    Directory of Open Access Journals (Sweden)

    Boczoń Andrzej

    2015-12-01

    Full Text Available Periodically occurring drought is typical for the climate of Poland. In habitats supplied exclusively with rain water, tree stands are frequently exposed to the negative effects of water deficit in the soil. The aim of this study was to examine the water uptake and consumption of two individual Scots pine trees under drought conditions. The trees were located at different positions within the stand and at the time of study were over 150 years old. Soil moisture, availability of soil water and the quantity of water uptake by the individual trees were examined by measuring the water velocity inside the trunks (Thermal Dissipation Probe method.

  11. On the relative contributions of wind vs. animals to seed dispersal of four Sierra Nevada pines.

    Science.gov (United States)

    Vander Wall, Stephen B

    2008-07-01

    Selective pressures that influence the form of seed dispersal syndromes are poorly understood. Morphology of plant propagules is often used to infer the means of dispersal, but morphology can be misleading. Several species of pines, for example, have winged seeds adapted for wind dispersal but owe much of their establishment to scatter-hoarding animals. Here the relative importance of wind vs. animal dispersal is assessed for four species of pines of the eastern Sierra Nevada that have winged seeds but differed in seed size: lodgepole pine (Pinus contorta murrayana, 8 mg); ponderosa pine (Pinus ponderosa ponderosa, 56 mg); Jeffrey pine (Pinus jeffreyi, 160 mg); and sugar pine (Pinus lambertiana, 231 mg). Pre-dispersal seed mortality eliminated much of the ponderosa pine seed crop (66%), but had much less effect on Jeffrey pine (32% of seeds destroyed), lodgepole pine (29%), and sugar pine (7%). When cones opened most filled seeds were dispersed by wind. Animals removed > 99% of wind-dispersed Jeffrey and sugar pine seeds from the ground within 60 days, but animals gathered only 93% of lodgepole pine seeds and 38% of ponderosa pine seeds during the same period. Animals gathered and scatter hoarded radioactively labeled ponderosa, Jeffrey, and sugar pine seeds, making a total of 2103 caches over three years of study. Only three lodgepole pine caches were found. Caches typically contained 1-4 seeds buried 5-20 mm deep, depths suitable for seedling emergence. Although Jeffrey and sugar pine seeds are initially wind dispersed, nearly all seedlings arise from animal caches. Lodgepole pine is almost exclusively wind dispersed, with animals acting as seed predators. Animals treated ponderosa pine in an intermediate fashion. Two-phased dispersal of large, winged pine seeds appears adaptive; initial wind dispersal helps to minimize pre-dispersal seed mortality whereas scatter hoarding by animals places seeds in sites with a higher probability of seedling establishment.

  12. ESTIMATION OF LEAF AREA INDEX IN OPEN-CANOPY PONDEROSA PINE FORESTS AT DIFFERENT SUCCESSIONAL STAGES AND MANAGEMENT REGIMES IN OREGON. (R828309)

    Science.gov (United States)

    AbstractLeaf area and its spatial distribution are key parameters in describing canopy characteristics. They determine radiation regimes and influence mass and energy exchange with the atmosphere. The evaluation of leaf area in conifer stands is particularly challengi...

  13. Composition and structure of managed pine stands compared to reference longleaf pine sites on Marine Corps Base Camp Lejeune, North Carolina

    Science.gov (United States)

    Joan L. Walker; Andrea M. Silletti; Susan Cohen

    2010-01-01

    We sampled the ground layer of 28 pine plantations to compare with ecological reference sites at Marine Corps Base, Camp Lejeune (MCBCL), NC. Plantations were ≥ 18 years old and had been burned within the previous year. Pines had been hand-planted on beds or fl at-planted, and the plantations were burned every 3 to 4 years after age 7. Data from 39 reference sites were...

  14. Xylem vulnerability to cavitation in Pseudotsuga menziesii and Pinus ponderosa from contrasting habitats.

    Science.gov (United States)

    Stout, Deborah H; Sala, Anna

    2003-01-01

    In the Rocky Mountains, ponderosa pine (Pinus ponderosa (ssp.) ponderosa Dougl. ex P. Laws. & C. Laws) often co-occurs with Douglas-fir (Pseudotsuga menziesii var. glauca (Mayr) Franco). Despite previous reports showing higher shoot vulnerability to water-stress-induced cavitation in ponderosa pine, this species extends into drier habitats than Douglas-fir. We examined: (1) whether roots and shoots of ponderosa pine in riparian and slope habitats are more vulnerable to water-stress-induced cavitation than those of Douglas-fir; (2) whether species-specific differences in vulnerability translate into differences in specific conductivity in the field; and (3) whether the ability of ponderosa pine to extend into drier sites is a result of (a) greater plasticity in hydraulic properties or (b) functional or structural adjustments. Roots and shoots of ponderosa pine were significantly more vulnerable to water-stress-induced cavitation (overall mean cavitation pressure, Psi(50%) +/- SE = -3.11 +/- 0.32 MPa for shoots and -0.99 +/- 0.16 MPa for roots) than those of Douglas-fir (Psi(50%) +/- SE = -4.83 +/- 0.40 MPa for shoots and -2.12 +/- 0.35 MPa for roots). However, shoot specific conductivity did not differ between species in the field. For both species, roots were more vulnerable to cavitation than shoots. Overall, changes in vulnerability from riparian to slope habitats were small for both species. Greater declines in stomatal conductance as the summer proceeded, combined with higher allocation to sapwood and greater sapwood water storage, appeared to contribute to the ability of ponderosa pine to thrive in dry habitats despite relatively high vulnerability to water-stress-induced cavitation.

  15. Restoration thinning and influence of tree size and leaf area to sapwood area ratio on water relations of Pinus ponderosa.

    Science.gov (United States)

    Simonin, K; Kolb, T E; Montes-Helu, M; Koch, G W

    2006-04-01

    Ponderosa pine (Pinus ponderosa Dougl. ex P. Laws) forest stand density has increased significantly over the last century (Covington et al. 1997). To understand the effect of increased intraspecific competition, tree size (height and diameter at breast height (DBH)) and leaf area to sapwood area ratio (A(L):A(S)) on water relations, we compared hydraulic conductance from soil to leaf (kl) and transpiration per unit leaf area (Q(L)) of ponderosa pine trees in an unthinned plot to trees in a thinned plot in the first and second years after thinning in a dense Arizona forest. We calculated kl and Q(L) based on whole- tree sap flux measured with heat dissipation sensors. Thinning increased tree predawn water potential within two weeks of treatment. Effects of thinning on kl and Q(L) depended on DBH, A(L):A(S) and drought severity. During severe drought in the first growing season after thinning, kl and Q(L) of trees with low A(L):A(S) (160-250 mm DBH; 9-11 m height) were lower in the thinned plot than the unthinned plot, suggesting a reduction in stomatal conductance (g(s)) or reduced sapwood specific conductivity (K(S)), or both, in response to thinning. In contrast kl and Q(L) were similar in the thinned plot and unthinned plot for trees with high A(L):A(S) (260-360 mm DBH; 13-16 m height). During non-drought periods, kl and Q(L) were greater in the thinned plot than in the unthinned plot for all but the largest trees. Contrary to previous studies of ponderosa pine, A(L):A(S) was positively correlated with tree height and DBH. Furthermore, kl and Q(L) showed a weak negative correlation with tree height and a strong negative correlation with A(S) and thus A(L):A(S) in both the thinned and unthinned plots, suggesting that trees with high A(L):A(S) had lower g(s). Our results highlight the important influence of stand competitive environment on tree-size-related variation in A(L):A(S) and the roles of A(L):A(S) and drought on whole-tree water relations in response to

  16. Intra-stand variation of cone structure and seed production in Siberian stone pine: pattern and use for breeding

    Directory of Open Access Journals (Sweden)

    V.S. Akimov

    2013-12-01

    Full Text Available Siberian stone pine (Pinus sibirica Du Tour in Russia is primarily valued as a nut-bearing species. Therefore, intra-standvariation in its cone structure and seed production have been actively studied during the last 50 years. However, these studies arepoorly related to practical breeding. We used a novel system of traits to characterize yearly seed crops at the different levels of itsstructural organization. The purpose is to analyze the results of long-term observations of the intra-stand variation of the reproductivefeatures complex, and to reveal the pattern and character of its diversity. This information would be useful to develop the method ofsearching the initial material for breeding. The research plot is established in the Nizhne-Sechenovo forest located 25 km fromTomsk in the south part of the boreal zone (170 years old, mean height 22 m, mean d.b.h. 60 cm. The number of sampled trees variedbetween 40-120 among years. The registration of seed crop and analysis of its structure was conducted every year from 1990 to 2005. Theintra-stand variation of the traits' level was determined as a standard deviation in percent from the simple average. The level ofvariability rose sharply and the correlations between them decreased in the years of the low crops. The results concerning variation in seedand cone traits are listed in the next table. The number of full seeds depended rather on losses in the processes of development (r =0.80*-0.85* than on their starting number (r =0.55*-0.60*. The mass of one seed with sound endosperm rose with an increase in the ratio ofthe ovules, which were lost at the earlier stagesof development (r = 0.20-0.25* and the flat seed ratio (r = 0.35*-0.40*. In year-to-year dynamics, the number of cones per tree ispositively connected with the number of filled seeds per cone (r = 0.78* and with other indices characterizing 'the crop quality'.The breeding rank of trees by all important

  17. Determining Clark's nutcracker use of whitebark pine communities in regard to stand health in Waterton-Glacier International Peace Park

    Science.gov (United States)

    Jennifer D. Scott; Diana F. Tomback; Michael B. Wunder

    2011-01-01

    Whitebark pine (Pinus albicaulis), one of five stone pines worldwide, is found at treeline and subalpine elevations in the mountains of western North America (McCaughey and Schmidt 2001). Considered a keystone species, it helps maintain subalpine biodiversity, protects watersheds and promotes post-fire regeneration (Tomback and others 2001). The Clark's nutcracker...

  18. Douglas-fir tussock moth- and Douglas-fir beetle-caused mortality in a ponderosa pine/Douglas-fir forest in the Colorado Front Range, USA

    Science.gov (United States)

    Jose F. Negron; Ann M. Lynch; Willis C. Schaupp; Vladimir Bocharnikov

    2014-01-01

    An outbreak of the Douglas-fir tussock moth, Orgyia pseudotsugata McDunnough, occurred in the South Platte River drainage on the Pike-San Isabel National Forest in the Colorado Front Range attacking Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco. Stocking levels, species composition, and tree size in heavily and lightly defoliated stands were similar. Douglas-fir...

  19. Modelling merchantable volumes for uneven aged maritime pine (Pinus pinaster Aiton stands establi-shed by natural regeneration in the central Portugal

    Directory of Open Access Journals (Sweden)

    Cristina Alegria

    2013-12-01

    Full Text Available Uneven aged maritime pine stands established by natural regeneration have a great expression in Portugal. These stands being overstocked, as opposed to those established from plantations, provide straight and cylindrical tree boles and logs with less knots that makes them very suitable for certain industrial purposes. Therefore, the aim of this study was to fit a set of equations to predict total volume and merchantable volumes to any merchantable limit for uneven aged maritime pine stands established by natural regeneration in the central inland region of Portugal. Data were collected in 30 circular sampling plots of 500 m2 of area, on 1426 trees and 314 sample trees for volume assessment, corresponding to 2353 diameter/height mea-surements. A total height equation, a total volume equation, a volume ratio equation to any top height limit and a taper equation, over bark, were fitted. To select among the best models, several statistics were computed during model fitting and the independent validation procedure to evaluate model fitting, collinearity and prediction performances. A ranking index was used to support the final decision. The models selected were then fitted again using robust regression and weighted regression techniques, because studentized residuals distribution normality and homogeneity assumptions were not observed. This research showed that the models selected for these stands were not the same as those selected in previous studies for the species in this region, suggesting that these results may be due to the influence of stand density conditions on diameter and total height growth, and consequently, on stem form and volume. This set of equations will also be included as components in a single tree growth and yield model developed for these stands

  20. Historic forests and endemic mountain pine beetle and dwarf mistletoe

    Science.gov (United States)

    Jose Negron

    2012-01-01

    Mountain pine beetle has always been a significant disturbance agent in ponderosa and lodgepole pine forests in Colorado. Most studies have examined the impacts to forest structure associated with epidemic populations of a single disturbance agent. In this paper we address the role of endemic populations of mountain pine and their interactions with dwarf mistletoe...

  1. Probability of infestation and extent of mortality models for mountain pine beetle in lodgepole pine forests in Colorado

    Science.gov (United States)

    Jose F. Negron; Jennifer G. Klutsch

    2017-01-01

    The mountain pine beetle, Dendroctonus ponderosae Hopkins, is a significant agent of tree mortality in lodgepole pine (Pinus contorta Dougl. ex Loud.) forests throughout western North America. A large outbreak of mountain pine beetle caused extensive tree mortality in north-central Colorado beginning in the late 1990s. We use data from a network of plots established in...

  2. Re-measurement of whitebark pine infection and mortality in the Canadian Rockies

    Science.gov (United States)

    Cyndi M. Smith; Brenda Shepherd; Cameron Gillies; Jon Stuart-Smith

    2011-01-01

    Whitebark pine (Pinus albicaulis) populations are under threat across the species' range from white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae), fire exclusion and climate change (Tomback and Achuff 2010). Loss of whitebark pine is predicted to have cascading effects on the following ecological services: provision of...

  3. Applied chemical ecology of the mountain pine beetle

    Science.gov (United States)

    Robert A. Progar; Nancy Gillette; Christopher J. Fettig; Kathryn Hrinkevich

    2014-01-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins, is a primary agent of forest disturbance in western North America. Episodic outbreaks occur at the convergence of favorable forest age and size class structure and climate patterns. Recent outbreaks have exceeded the historic range of variability of D. ponderosae-caused tree mortality affecting ecosystem goods and...

  4. A Comment on “Management for Mountain Pine Beetle Outbreak Suppression: Does Relevant Science Support Current Policy?”

    Directory of Open Access Journals (Sweden)

    Christopher J. Fettig

    2014-04-01

    Full Text Available There are two general approaches for reducing the negative impacts of mountain pine beetle, Dendroctonus ponderosae Hopkins, on forests. Direct control involves short-term tactics designed to address current infestations by manipulating mountain pine beetle populations, and includes the use of fire, insecticides, semiochemicals, sanitation harvests, or a combination of these treatments. Indirect control is preventive, and designed to reduce the probability and severity of future infestations within treated areas by manipulating stand, forest and/or landscape conditions by reducing the number of susceptible host trees through thinning, prescribed burning, and/or alterations of age classes and species composition. We emphasize that “outbreak suppression” is not the intent or objective of management strategies implemented for mountain pine beetle in the western United States, and that the use of clear, descriptive language is important when assessing the merits of various treatment strategies.

  5. A Pine Is a Pine and a Spruce Is a Spruce--The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities.

    Science.gov (United States)

    Bäcklund, Sofia; Jönsson, Mari; Strengbom, Joachim; Frisch, Andreas; Thor, Göran

    2016-01-01

    With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden.

  6. A Pine Is a Pine and a Spruce Is a Spruce--The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities.

    Directory of Open Access Journals (Sweden)

    Sofia Bäcklund

    Full Text Available With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden.

  7. A Pine Is a Pine and a Spruce Is a Spruce – The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities

    Science.gov (United States)

    Bäcklund, Sofia; Jönsson, Mari; Strengbom, Joachim; Frisch, Andreas; Thor, Göran

    2016-01-01

    With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden. PMID:26799558

  8. Pine needle abortion in cattle update: Metabolite detection in sera and fetal fluids from abortion case samples

    Science.gov (United States)

    Cattle abortions associated with consumption of pine needles during late gestation are a serious poisonous plant problem in the Western US. Most cases of abortion have been associated with consumption of ponderosa pine (Pinus ponderosa) and the causative agent was identified as the labdane diterpen...

  9. Seed release in serotinous lodgepole pine forests after mountain pine beetle outbreak.

    Science.gov (United States)

    Teste, François P; Lieffers, Victor J; Landhausser, Simon M

    2011-01-01

    There are concerns that large-scale stand mortality due to mountain pine beetle (MPB) could greatly reduce natural regeneration of serotinous Rocky Mountain (RM) lodgepole pine (Pinus contorta var. latifolia) because the closed cones are held in place without the fire cue for cone opening. We selected 20 stands (five stands each of live [control], 3 years since MPB [3-yr-MPB], 6 years since MPB [6-yr-MPB], and 9 years since MPB [9-yr-MPB] mortality) in north central British Columbia, Canada. The goal was to determine partial loss of serotiny due to fall of crown-stored cones via breakage of branches and in situ opening of canopy cones throughout the 2008 and 2009 growing seasons. We also quantified seed release by the opening of forest-floor cones, loss of seed from rodent predation, and cone burial. Trees killed by MPB three years earlier dropped approximately 3.5 times more cones via branch breakage compared to live stands. After six years, MPB-killed stands had released 45% of their canopy seed bank through cone opening, cone fall due to breakage, and squirrel predation. Further losses of canopy seed banks are expected with time since we found 9-yr-MPB stands had 38% more open canopy cones. This was countered by the development of a modest forest-floor seed bank (6% of the original canopy seed bank) from burial of cones; this seed bank may be ecologically important if a fire or anthropogenic disturbance reexposes these cones. If adequate levels of regeneration are to occur, disturbances to create seedbeds must occur shortly after tree mortality, before the seed banks are lost. Our findings also suggest that the sustained seed rain (over at least nine years) after MPB outbreak may be beneficial for population growth of ground-foraging vertebrates. Our study adds insight to the seed ecology of serotinous pines under a potentially continental-wide insect outbreak, threatening vast forests adapted to regeneration after fire. Key words: biotic disturbance; cone

  10. Mountain pine beetle attack alters the chemistry and flammability of lodgepole pine foliage

    Science.gov (United States)

    Wesley G. Page; Michael J. Jenkins; Justin B. Runyon

    2012-01-01

    During periods with epidemic mountain pine beetle (Dendroctonus ponderosae Hopkins) populations in lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forests, large amounts of tree foliage are thought to undergo changes in moisture content and chemistry brought about by tree decline and death. However, many of the presumed changes have yet to be...

  11. Is lodgepole pine mortality due to mountain pine beetle linked to the North American Monsoon?

    Science.gov (United States)

    Sara A. Goeking; Greg C. Liknes

    2012-01-01

    Regional precipitation patterns may have influenced the spatial variability of tree mortality during the recent mountain pine beetle (Dendroctonus ponderosa) (MPB) outbreak in the western United States. Data from the Forest Inventory and Analysis (FIA) Program show that the outbreak was especially severe in the state of Colorado where over 10 million lodgepole pines (...

  12. Mountain pine beetle-killed lodgepole pine for the production of submicron lignocellulose fibrils

    Science.gov (United States)

    Ingrid Hoeger; Rolland Gleisner; Jose Negron; Orlando J. Rojas; J. Y. Zhu

    2014-01-01

    The elevated levels of tree mortality attributed to mountain pine beetle (MPB) (Dendroctonus ponderosae Hopkins) in western North American forests create forest management challenges. This investigation introduces the production of submicron or nanometer lignocellulose fibrils for value-added materials from the widely available resource represented by dead pines after...

  13. Soil microbiological properties and enzymatic activities of long-term post-fire recovery in dry and semiarid Aleppo pine (Pinus halepensis M.) forest stands

    Science.gov (United States)

    Hedo, J.; Lucas-Borja, M. E.; Wic, C.; Andrés-Abellán, M.; de Las Heras, J.

    2015-02-01

    Wildfires affecting forest ecosystems and post-fire silvicultural treatments may cause considerable changes in soil properties. The capacity of different microbial groups to recolonise soil after disturbances is crucial for proper soil functioning. The aim of this work was to investigate some microbial soil properties and enzyme activities in semiarid and dry Aleppo pine (Pinus halepensis M.) forest stands. Different plots affected by a wildfire event 17 years ago without or with post-fire silvicultural treatments 5 years after the fire event were selected. A mature Aleppo pine stand, unaffected by wildfire and not thinned was used as a control. Physicochemical soil properties (soil texture, pH, carbonates, organic matter, electrical conductivity, total N and P), soil enzymes (urease, phosphatase, β-glucosidase and dehydrogenase activities), soil respiration and soil microbial biomass carbon were analysed in the selected forests areas and plots. The main finding was that long time after this fire event produces no differences in the microbiological soil properties and enzyme activities of soil after comparing burned and thinned, burned and not thinned, and mature plots. Moreover, significant site variation was generally seen in soil enzyme activities and microbiological parameters. We conclude that total vegetation recovery normalises post-fire soil microbial parameters, and that wildfire and post-fire silvicultural treatments are not significant factors affecting soil properties after 17 years.

  14. Summary of preliminary step-trend analysis from the Interagency Whitebark Pine Long-termMonitoring Program—2004-2013

    Science.gov (United States)

    Legg, Kristin; Shanahan, Erin; Daley, Rob; Irvine, Kathryn M.

    2014-01-01

    In mixed and dominant stands, whitebark pine (Pinus albicaulis) occurs in over two million acres within the six national forests and two national parks that comprise the Greater Yellowstone Ecosystem (GYE). Currently, whitebark pine, an ecologically important species, is impacted by multiple ecological disturbances; white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae), wildfire, and climate change all pose significant threats to the persistence of whitebark pine populations. Substantial declines in whitebark pine populations have been documented throughout its range.Under the auspices of the Greater Yellowstone Coordinating Committee (GYCC), several agencies began a collaborative, long-term monitoring program to track and document the status of whitebark pine across the GYE. This alliance resulted in the formation of the Greater Yellowstone Whitebark Pine Monitoring Working Group (GYWPMWG), which consists of representatives from the U.S. Forest Service (USFS), National Park Service (NPS), U.S. Geological Survey (USGS), and Montana State University (MSU). This groundbased monitoring program was initiated in 2004 and follows a peer-reviewed protocol (GYWPMWG 2011). The program is led by the Greater Yellowstone Inventory and Monitoring Network (GRYN) of the National Park Service in coordination with multiple agencies. More information about this monitoring effort is available at: http://science. nature.nps.gov/im/units/gryn/monitor/whitebark_pine.cfm. The purpose of this report is to provide a draft summary of the first step-trend analysis for the interagency, long-term monitoring of whitebark pine health to the Interagency Grizzly Bear Study Team (IGBST) as part of a synthesis of the state of whitebark pine in the GYE. Due to the various stages of the analyses and reporting, this is the most efficient way to provide these results to the IGBST.

  15. Vertical Distribution of Radiation and Energy Balance Partitioning Within and Above a Lodgepole Pine Stand Recovering from a Recent Insect Attack

    Science.gov (United States)

    Emmel, Carmen; Paul-Limoges, Eugenie; Black, Thomas Andrew; Christen, Andreas

    2013-11-01

    The current outbreak of mountain pine beetle (MPB) that started in the late 1990s in British Columbia, Canada, is the largest ever recorded in the north American native habitat of the beetle. The killing of trees is expected to change the vertical distribution of net radiation () and the partitioning of latent () and sensible () heat fluxes in the different layers of an attacked forest canopy. During an intensive observation period in the summer of 2010, eddy-covariance flux and radiation measurements were made at seven heights from ground level up to 1.34 times the canopy height in an MPB-attacked open-canopy forest stand in the interior of British Columbia, Canada. The lodgepole pine dominated stand with a rich secondary structure (trees and understorey not killed by the beetle) was first attacked by the MPB in 2003 and received no management. In this study, the vertical distribution of the energy balance components and their sources and sinks were analyzed and energy balance closure (EBC) was determined for various levels within the canopy. The low stand density resulted in approximately 60 % of the shortwave irradiance and 50 % of the daily total reaching the ground. Flux divergence calculations indicated relatively strong sources of latent heat at the ground and where the secondary structure was located. Only very weak sources of latent heat were found in the upper part of the canopy, which was mainly occupied by dead lodgepole pine trees. was the dominant term throughout the canopy, and the Bowen ratio () increased with height in the canopy. Soil heat flux () accounted for approximately 4 % of . Sensible heat storage in the air () was the largest of the energy balance storage components in the upper canopy during daytime, while in the lower canopy sensible heat storage in the boles () and biochemical energy storage () were the largest terms. was almost constant from the bottom to above the canopy. , and latent heat storage in the air () varied more than

  16. Liming with powdered oil-shale ash in a heavily damaged forest ecosystem. 2.The effect on forest condition in a pine stand

    International Nuclear Information System (INIS)

    Terasmaa, T.; Pikk, J.

    1995-01-01

    First years after the treatment (in 1987) of forest soil with mineral fertilizers and powdered oil-shale ash in a heavily damaged 50-year-old Scots pine ecosystem showed a comparatively small effect (B<0.95) of liming on the stand characters. However, in comparison with the effect of only NPK fertilization on the volume growth and the health state of trees, liming (NPK+oil-shale ash) tended to increase the positive influence of fertilizers. Under the influence of oil-shale ash the mortality of the trees was lower, the density of the stand rose more, and the mean radial increment of trees was by 26% greater than after the NPK treatment without a lime agent. On the whole, the effect of oil-shale ash liming on the growth and health condition of the pine stand was not high. However, the first results of its experimental use on mineral forest soil cannot serve as the basis for essential conclusions. Still, the results give us some assurance to continue our experimental work with powdered oil-shale ash in forests with the purpose of regulating the high acidity of forest soils in some sites to gain positive shifts in the forest life. Taking into account the low price of the powdered oil-shale ash and the plentiful resources of this liming material in Estonia, even a small trend towards an improvement of forest condition on poor sandy soils would be a satisfactory final result of the work. It is essential to note that oil-shale ash is not only a simple liming material, but also a lime fertilizer consisting of numerous chemical elements necessary for plant growth. 2 tabs., 3 figs., 18 refs

  17. Modeling the effects of fire and climate change on carbon and nitrogen storage in lodgepole pine (Pinus contorta) stands

    Science.gov (United States)

    E. A. H. Smithwick; M. G. Ryan; D. M. Kashian; W. H. Romme; D. B. Tinker; M. G. Turner

    2009-01-01

    The interaction between disturbance and climate change and resultant effects on ecosystem carbon (C) and nitrogen (N) fluxes are poorly understood. Here, we model (using CENTURY version 4.5) how climate change may affect C and N fluxes among mature and regenerating lodgepole pine (Pinus contorta var. latifolia Engelm. ex S.Wats.)...

  18. Do climate and outbreak frequency affect levels of foliar phytochemistry in different lodgepole pine (Pinus contorta) stands?

    Science.gov (United States)

    Lodgepole pine (Pinus contorta Douglas ex Louden) is a widely distributed tree in North American forests and is found in a variety of environments, each with different levels of disease activity. We quantified the levels of defense-associated metabolites (including soluble phenolics, lignin, and ter...

  19. Effect of seedling stock on the early stand development and physiology of improved loblolly pine (Pinus taeda L.) seedlings

    Science.gov (United States)

    Shakuntala Sharma; Joshua P. Adams; Jamie L. Schuler; Robert L. Ficklin; Don C. Bragg

    2016-01-01

    This study assessed the effects of spacing and genotype on the growth and physiology of improved loblolly pine (Pinus taeda L.) seedlings from three distinct genotypes planted in Drew County, Arkansas (USA). Genotype had a significant effect on survival and height. Clone CF Var 1 showed greater height and survival compared to other seedlings....

  20. Net ecosystem productivity and its environmental controls in a mature Scots pine stand in north-western Poland

    Czech Academy of Sciences Publication Activity Database

    Ziemblinska, K.; Urbaniak, M.; Chojnicki, B. H.; Black, T. A.; Niu, S.; Olejnik, Janusz

    2016-01-01

    Roč. 228, nov (2016), s. 60-72 ISSN 0168-1923 Institutional support: RVO:67179843 Keywords : Scots pine * eddy covariance * environmental controls * net ecosystem productivity * southern Finland Subject RIV: EH - Ecology, Behaviour Impact factor: 3.887, year: 2016

  1. Planting density and silvicultural intensity impacts on loblolly pine stand development in the western gulf coastal plain through age 8

    Science.gov (United States)

    Michael B. Kane; Dehai Zhao; John W. Rheney; Michael G. Messina; Mohd S. Rahman; Nicholas Chappell

    2012-01-01

    Commercial plantation growers need to know how planting density and cultural regime intensity affect loblolly pine plantation productivity, development and value to make sound management decisions. This knowledge is especially important given the diversity of traditional products, such as pulpwood, chip-n-saw, and sawtimber, and potential products, such as bioenergy...

  2. Stand conditions and tree characteristics affect quality of longleaf pine for red-cockaded woodpecker cavity trees

    Science.gov (United States)

    W.G. Ross; D.L. Kulhavy; R.N. Conner

    1997-01-01

    We measured resin flow of longleaf (Pinus palustris Mill.) pines in red-cockaded woodpecker (Picoides borealis Vieillot) clusters in the Angelina National Forest in Texas, and the Apalachicola National Forest in Florida. Sample trees were categorized as active cavity trees, inactive cavity trees and control trees. Sample trees were further...

  3. Interaction of an invasive bark beetle with a native forest pathogen: Potential effect of dwarf mistletoe on range expansion of mountain pine beetle in jack pine forests

    Science.gov (United States)

    Jennifer Klutsch; Nadir Erbilgin

    2012-01-01

    In recent decades, climate change has facilitated shifts in species ranges that have the potential to significantly affect ecosystem dynamics and resilience. Mountain pine beetle (Dendroctonus ponderosae) is expanding east from British Columbia, where it has killed millions of pine trees, primarily lodgepole pine (Pinus contorta...

  4. First report of Fusarium proliferatum causing Fusarium root disease on sugar pine (Pinus lambertiana) in a forest container nursery in California

    Science.gov (United States)

    J. E. Stewart; K. Otto; G. A. Cline; Kas Dumroese; Ned Klopfenstein; M. -S. Kim

    2016-01-01

    Fusarium species, specifically F. commune, F. proliferatum, and F. solani, can cause severe damping-off and root disease in container and bareroot forest nurseries throughout North America. Many conifer and hardwood species can be affected, but Douglas-fir (Pseudotsuga menziesii), western white pine (Pinus monticola), and ponderosa pine (P. ponderosa) are known to be...

  5. Forest development and carbon dynamics after mountain pine beetle outbreaks

    Science.gov (United States)

    E. Matthew. Hansen

    2014-01-01

    Mountain pine beetles periodically infest pine forests in western North America, killing many or most overstory pine stems. The surviving secondary stand structure, along with recruited seedlings, will form the future canopy. Thus, even-aged pine stands become multiaged and multistoried. The species composition of affected stands will depend on the presence of nonpines...

  6. Length Research Paper The effects of the pine processionary moth ...

    African Journals Online (AJOL)

    The pine processionary moth (PPM), causing significant damage on pine stands in Turkey, affects mainly crimean pine stands within the Ulus vicinity. To determine the damage, 20 sample plots of second site class crimean pine stands were measured; 10 of which were taken as the control sample and 10 of which were ...

  7. Impact of Hurricane Ivan on the regional longleaf pine growth study: is there a relation to site or stand conditions?

    Science.gov (United States)

    John S. Kush; John C. Gilbert

    2010-01-01

    The US Forest Service Regional Longleaf Pine Growth Study (RLGS) began its eighth re-measurement (40th year) during 2004 autumn. The study has 305 plots of which 171 plots are located on the Escambia Experimental Forest (EEF) in Brewton AL. EEF is operated by the U.S. Forest Service in cooperation with the T.R. Miller Mill Company. The RLGS has plots distributed across...

  8. Influence of stand density and soil treatment on the Spanish Black Pine (Pinus nigra Arn. ssp. Salzmannii) regeneration in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Cerro Barja, A. del; Lucas-Borja, M. E.; Martinez Garcia, E.; Lopez Serrano, F. R.; Andres Abellan, M.; Garcia Morote, F. A.; Navarro Lopez, R.

    2009-07-01

    Satisfactory results relating to the natural regeneration of the Spanish black pine (Pinus nigra Arn ssp. salzmannii) is generally difficult to achieve. The natural regeneration of this pine was studied comparing two types of soil treatment and various over story densities in six experimental forests. These studies were conducted from 1999 to 2002 and seed rain and germination, as well as seedling survival were observed in a number of specific plots: Brushing, scalping and control plots. In addition various over story densities were used (measured as base area m2/ha). Soil and air temperature together with soil moisture were continuously recorded throughout this summer period. The results showed that seed germination was higher in plots using the scalping technique, as opposed to the brushed or controlled plots. The best seedling survival percentage was found in scalped plots together with a larger basal area. It was also found that seedling survival was lower during the first year than during the second one. The results have practical implications for management of Spanish black pine forests as well as valuable information which could improve the conditions for regeneration. (Author) 82 refs.

  9. Effects of lime and wood ash on soil-solution chemistry, soil chemistry and nutritional status of a pine stand in northern Germany

    International Nuclear Information System (INIS)

    Ludwig, Bernard; Rumpf, Sabine; Mindrup, Michael; Meiwes, Karl-Josef; Khanna, Partap K.

    2002-01-01

    Lime and wood ash may be useful to improve acidic forest soils. A field experiment was conducted in a pine stand on a sandy podzol at Fuhrberg, Germany, which involved an application of dolomitic lime (3 t/ha) with three replications or wood ash (4.8 t/ha) without replications on the forest floor. During the 2 yr study period, lime affected the soil solution composition only slightly. Ash had a marked effect on solution chemistry of the mineral soil at 10 cm and the pH values dropped temporarily from 3.7 to 3.1. Nineteen months after the treatments, exchangeable calcium in the organic layer and mineral soil increased by 222 (lime addition) or 411 kg/ha (ash addition) and exchangeable magnesium increased by 101 (lime addition) or 39 kg/ha (ash addition). After ash addition, no marked change in heavy metal content was found below 4 cm of the organic layer. In the ash treatment, the potassium concentration of the 1-yr-old pine needles increased from 5.6 to 5.9 g/kg. This study suggests that ash from untreated wood may be recommended for amelioration of forest soils

  10. A survey of cavity-nesting bees and wasps in loblolly pine stands of the Savannah River Site, Aiken County, South Carolina.

    Energy Technology Data Exchange (ETDEWEB)

    Horn, S.; Hanula, J., L.

    2004-03-10

    Horn, Scott, and James L. Hanula. 2004. A survey of cavity-nesting bees and wasps in loblolly pine stands of the Savannah River Site, Aiken County, South Carolina. 39(3): 464-469. Abstract: In recent years concern over widespread losses in biodiversity has grown to include a possible decline of many native pollinators, primarily bees. Factors such as habitat fragmentation, agricultural practices, use of pesticides, the introduction of invasive species, or changes in land use may negatively impact these vital organisims. Most reported studies show that human impacts on pollinators are overwhelmingly negative. Reductions in pollinator populations may profoundly impact plant population dynamics and ecosystem function. Little baseline data exists on the diversity and relative abundance of bees and wasps in southern forests. The objective of this study was to develop a simple, effective method of surveying cavity-nesting bees and wasps and to determine species diversity in mature forests of loblolly pine, the most widely planted tree species in the southern United States.

  11. PONDEROSA-C/S: client-server based software package for automated protein 3D structure determination.

    Science.gov (United States)

    Lee, Woonghee; Stark, Jaime L; Markley, John L

    2014-11-01

    Peak-picking Of Noe Data Enabled by Restriction Of Shift Assignments-Client Server (PONDEROSA-C/S) builds on the original PONDEROSA software (Lee et al. in Bioinformatics 27:1727-1728. doi: 10.1093/bioinformatics/btr200, 2011) and includes improved features for structure calculation and refinement. PONDEROSA-C/S consists of three programs: Ponderosa Server, Ponderosa Client, and Ponderosa Analyzer. PONDEROSA-C/S takes as input the protein sequence, a list of assigned chemical shifts, and nuclear Overhauser data sets ((13)C- and/or (15)N-NOESY). The output is a set of assigned NOEs and 3D structural models for the protein. Ponderosa Analyzer supports the visualization, validation, and refinement of the results from Ponderosa Server. These tools enable semi-automated NMR-based structure determination of proteins in a rapid and robust fashion. We present examples showing the use of PONDEROSA-C/S in solving structures of four proteins: two that enable comparison with the original PONDEROSA package, and two from the Critical Assessment of automated Structure Determination by NMR (Rosato et al. in Nat Methods 6:625-626. doi: 10.1038/nmeth0909-625 , 2009) competition. The software package can be downloaded freely in binary format from http://pine.nmrfam.wisc.edu/download_packages.html. Registered users of the National Magnetic Resonance Facility at Madison can submit jobs to the PONDEROSA-C/S server at http://ponderosa.nmrfam.wisc.edu, where instructions, tutorials, and instructions can be found. Structures are normally returned within 1-2 days.

  12. Northern Idaho ponderosa racial variation study - 50-year results

    Science.gov (United States)

    R. J. Steinhoff

    1970-01-01

    Ponderosa pine trees from 19 geographic sources planted on a test area in northern Idaho have been measured 12, 20, 40, and 50 years after outplanting. From the 12th through the 50th years after outplanting, trees from one nonlocal source have been tallest. Trees from the local source now rank second in height, having risen from sixth during the last 10 years. In...

  13. Optimization Forest Thinning Measures for Carbon Budget in a Mixed Pine-Oak Stand of the Qingling Mountains, China: A Case Study

    Directory of Open Access Journals (Sweden)

    Lin Hou

    2016-11-01

    Full Text Available Forest thinning is a silviculture treatment for sustainable forest management. It may promote growth of the remaining individuals by decreasing stand density, reducing competition, and increasing light and nutrient availability to increase carbon sequestration in the forest ecosystem. However, the action also increases carbon loss simultaneously by reducing carbon and other nutrient inputs as well as exacerbating soil CO2 efflux. To achieve a maximum forest carbon budget, the central composite design with two independent variables (thinning intensity and thinning residual removal rate was explored in a natural pine-oak mixed stand in the Qinling Mountains, China. The net primary productivity of living trees was estimated and soil CO2 efflux was stimulated by the Yasso07 model. Based on two years observation, the preliminary results indicated the following. Evidently chemical compounds of the litter of the tree species affected soil CO2 efflux stimulation. The thinning residual removal rate had a larger effect than thinning intensity on the net ecosystem productivity. When the selective thinning intensity and residual removal rate was 12.59% and 66.62% concurrently, the net ecosystem productivity reached its maximum 53.93 t·ha−1·year−1. The lower thinning intensity and higher thinning residual removal rated benefited the net ecosystem productivity.

  14. Responses of arthropods to large-scale manipulations of dead wood in loblolly pine stands of the southeastern United States.

    Science.gov (United States)

    Ulyshen, Michael D; Hanula, James L

    2009-08-01

    Large-scale experimental manipulations of dead wood are needed to better understand its importance to animal communities in managed forests. In this experiment, we compared the abundance, species richness, diversity, and composition of arthropods in 9.3-ha plots in which either (1) all coarse woody debris was removed, (2) a large number of logs were added, (3) a large number of snags were added, or (4) no coarse woody debris was added or removed. The target taxa were ground-dwelling arthropods, sampled by pitfall traps, and saproxylic beetles (i.e., dependent on dead wood), sampled by flight intercept traps and emergence traps. There were no differences in total ground-dwelling arthropod abundance, richness, diversity, or composition among treatments. Only the results for ground beetles (Carabidae), which were more species rich and diverse in log input plots, supported our prediction that ground-dwelling arthropods would benefit from additions of dead wood. There were also no differences in saproxylic beetle abundance, richness, diversity, or composition among treatments. The findings from this study are encouraging in that arthropods seem less sensitive than expected to manipulations of dead wood in managed pine forests of the southeastern United States. Based on our results, we cannot recommend inputting large amounts of dead wood for conservation purposes, given the expense of such measures. However, the persistence of saproxylic beetles requires that an adequate amount of dead wood is available in the landscape, and we recommend that dead wood be retained whenever possible in managed pine forests.

  15. Cultural intensity and planting density effects on individual tree stem growth, stand and crown attributes, and stand dynamics in thinned loblolly pine plantations during the age 12- to age 15- year period in the Upper Coastal Plain and Piedmont of the Southeastern United States

    Science.gov (United States)

    Evan Johnson; Michael Kane; Dehai Zhao; Robert Teskey

    2015-01-01

    Three existing loblolly pine (Pinus taeda L.) installations in the Plantation Management Research Cooperative's Upper Coastal Plain/Piedmont Culture Density Study were used to examine the effects of two cultural intensities, four initial planting densities, and their interactions on stem growth at the individual tree level from age 12 to 15 years and at the stand...

  16. Evaluating ozone air pollution effects on pines in the western United States

    Science.gov (United States)

    Paul R. Miller; Kenneth W. Stolte; Daniel M. Duriscoe; John Pronos

    1996-01-01

    Historical and technical background is provided about ozone air pollution effects on ponderosa (Pinus ponderosa Dougl. ex Laws) and Jeffrey (P. jeffreyi Grev. and Balf.) pines in forests of the western United States. The principal aim is to document the development of field survey methods to be applied to assessment of chronic...

  17. Developing contemporary and historical live tree biomass estimates for old pine-hardwood stands of the Midsouth, USA

    Science.gov (United States)

    Don C. Bragg

    2012-01-01

    Calculating stand biomass potential is an increasingly important aspect of silviculture, particularly when attempting to restore forest ecosystems or determining additionality in sequestered carbon. However, the lumbering of the original forests of the Midsouth region of the United States of America, coupled with the accelerating conversion of unmanaged natural-origin...

  18. 77 FR 10717 - Black Hills National Forest, Custer, South Dakota-Mountain Pine Beetle Response Project

    Science.gov (United States)

    2012-02-23

    .... The predominant tree species on lands of all ownerships in the Black Hills is ponderosa pine (Pinus... drought the Forest has seen a dramatic increase in acreage burned by wildfires. In that period over 250...

  19. Comparisons of xylem sap flow and water vapour flux at the stand level and derivation of canopy conductance for Scots pine

    Science.gov (United States)

    Granier, A.; Biron, P.; Köstner, B.; Gay, L. W.; Najjar, G.

    1996-03-01

    Simultaneous measurements of xylem sap flow and water vapour flux over a Scots pine ( Pinus sylvestris) forest (Hartheim, Germany), were carried out during the Hartheim Experiment (HartX), an intensive observation campaign of the international programme REKLIP. Sap flow was measured every 30 min using both radial constant heating (Granier, 1985) and two types of Cermak sap flowmeters installed on 24 trees selected to cover a wide range of the diameter classes of the stand (min 8 cm; max 17.5 cm). Available energy was high during the observation period (5.5 to 6.9 mm.day-1), and daily cumulated sap flow on a ground area basis varied between 2.0 and 2.7 mm day-1 depending on climate conditions. Maximum hourly values of sap flow reached 0.33 mm h-1, i.e., 230 W m-2. Comparisons of sap flow with water vapour flux as measured with two OPEC (One Propeller Eddy Correlation, University of Arizona) systems showed a time lag between the two methods, sap flow lagging about 90 min behind vapour flux. After taking into account this time lag in the sap flow data set, a good agreement was found between both methods: sap flow = 0.745* vapour flux, r 2 = 0.86. The difference between the two estimates was due to understory transpiration. Canopy conductance ( g c ) was calculated from sap flow measurements using the reverse form of Penman-Monteith equation and climatic data measured 4 m above the canopy. Variations of g c were well correlated ( r 2 = 0.85) with global radiation ( R) and vapour pressure deficit ( vpd). The quantitative expression for g c = f ( R, vpd) was very similar to that previously found with maritime pine ( Pinus pinaster) in the forest of Les Landes, South Western France.

  20. Liming with powdered oil-shale ash in a heavily damaged forest ecosystem. 1.The effect on forest soil in a pine stand

    International Nuclear Information System (INIS)

    Terasmaa, T.; Sepp, S.

    1994-01-01

    A fertilization and liming experiment with mineral fertilizers and powdered oil-shale ash was carried out in a heavily damaged 50-year-old Scots pine ecosystem in South Estonia. In Estonia, where electric power is produced mainly in big oil-shale-fired power plants, huge quantities of SO 2 are flying into the atmosphere through the chimneys of the plants. However, it is characteristic of Estonia that simultaneously with comparatively high SO 2 pollution the proton load has been quite low because of big amounts of alkali c ash emitted together with SO 2 into the atmosphere through the chimneys of the thermal power plants. Therefore, acid rains are not frequent in Estonia. Acid precipitation here is caused mainly by SO 2 released in the central part of Europe. In Estonia acid rains are most frequently registered in the southern area of the country. At times rains with pH values below 5.1 (even 4.0 and lower) have been registered there. This is also the region where quite severely damaged pine forests can be found. As a rule, these forests grow on acid sandy soils poor in nutrients and bases. The aim of the present study was to investigate the possibility of using oil shale ash as a liming agent in a forest ecosystem for protecting forest soils from acidification and, together with some mineral fertilizers, for improving the health of injured pine stands. In Estonia the most easily available liming agent is powdered oil-shale ash, which has been widely used as a lime fertilizer for agricultural crops but so far has not been tested for liming forests on mineral soils. The comparison of the present study with the liming experiments carried out with limestone in Finland shows that the effect of oil-shale ash treatment of acid sandy soils to raise pH values and to reduce other characteristics of soil acidity was more effective than limestone liming of mineral soils in Finnish forests. The present study demonstrates that powdered oil-shale ash is highly effective in short

  1. Postfire environmental conditions influence the spatial pattern of regeneration for Pinus ponderosa

    Science.gov (United States)

    V. H. Bonnet; Anna Schoettle; W. D. Shepperd

    2005-01-01

    Regeneration of ponderosa pine after fire depends on the patterns of seed availability and the environmental conditions that define safe sites for seedling establishment. A transect approach was applied in 2002 to determine the spatial distribution of regeneration from unburned to burned areas within the landscape impacted by the Jasper Fire of 2000 in the...

  2. Response of old-growth conifers to reduction in stand density in western Oregon forests

    Science.gov (United States)

    Latham, P.; Tappeiner, J. C.

    2002-01-01

    The positive growth response of healthy young trees to density reduction is well known. In contrast, large old trees are usually thought to be intrinsically limited in their ability to respond to increased growing space; therefore, density reduction is seldom used in stands of old-growth trees. We tested the null hypothesis that old-growth trees are incapable of responding with increased growth following density reduction. The diameter growth response of 271 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), ponderosa pine (Pinus ponderosa Dougl. ex Laws) and sugar pine (Pinus lambertiana Dougl.) trees ranging in age from 158 to 650 years was examined 20 to 50 years after density reduction. Density reduction involved either light thinning with removal of less vigorous trees, or shelterwood treatments in which overstory trees were not removed. Ratios of basal area growth after treatment to basal area growth before treatment, and several other measures of growth, all indicated that the old trees sometimes benefited and were not harmed by density reduction. Growth increased by 10% or more for 68% of the trees in treated stands, and nearly 30% of trees increased growth by over 50%. This growth response persisted for at least 20 years. During this 20-year period, only three trees in treated stands (1.5%) exhibited a rapid decrease in growth, whereas growth decreased in 64% of trees in untreated stands. The length of time before a growth response to density reduction occurred varied from 5 to 25 years, with the greatest growth response often occurring 20 to 25 years after treatment. These results have important implications both for the basic biology of aging in woody plants as well as for silvicultural practices in forests with old-growth trees.

  3. Interactions between canopy cover density and regeneration cores of older saplings in Scots pine (Pinus sylvestris L.) stands

    Energy Technology Data Exchange (ETDEWEB)

    Marchi, M.; Nocentini, S.; Ducci, F.

    2016-07-01

    Aim of the study: This paper provides an analysis of growth and survival of twenty–year–old Scots pine saplings in relation to canopy cover density (CCD) gradients, from dense (D–CCD), sparse (S–CCD), and gap (G–CCD) situations. Area of study: Aladag (Bolu) in northern Turkey. Material and methods: Sparse canopy cover density (S–CCD), dense canopy cover density (D–CCD) and gap canopy (G–CCD) were chosen within ten different strip sample plots (10 × 50 m) with sapling regeneration cores. Those regeneration cores were divided into two portions (individuals at the edge and middle of the regeneration cores) and from each portion three individuals was were obtained from a sample. The growth relationships of individual saplings were calculated with stem analyses. Honowski Light Factor (HLF) (ratio of Terminal sprout length (T) to Lateral sprout length (L)) was used to present growth potential measure of seedlings. Main results: The largest sapling regeneration cores were found in the G–CCD followed by S–CCD, and finally D–CCD, all tested for significance with Kruskal–Wallis Test. Compared with saplings in the middle of regeneration cores (crop saplings), those at the edge were always reduced in terms of mean height. Significant difference was only found between the ‘Main Crop’ and the ‘Edge 1’ of the regeneration cores for G–CCD suggesting that sapling regeneration cores are more typical under G–CCD conditions. HLF ratios were greater than 1 with high growth potentials for both CCD gradients (G–CCD and S–CCD) and there were no significant variations between G–CCD and S–CCD for main crop and edges. The thinning after 12–14 years increased sapling growth. However, under D–CCD, growth had virtually ceased. Research highlights: Naturally occurring Scots pine saplings are suppressed by a dense canopy. However, they are tolerant of shade to the extent that they can survive over relatively long time–periods (10–12 years) and

  4. Retrieving forest stand parameters from SAR backscatter data using a neural network trained by a canopy backscatter model

    International Nuclear Information System (INIS)

    Wang, Y.; Dong, D.

    1997-01-01

    It was possible to retrieve the stand mean dbh (tree trunk diameter at breast height) and stand density from the Jet Propulsion Laboratory (JPL) Airborne Synthetic Aperture Radar (AIRSAR) backscatter data by using threelayered perceptron neural networks (NNs). Two sets of NNs were trained by the Santa Barbara microwave canopy backscatter model. One set of the trained NNs was used to retrieve the stand mean dbh, and the other to retrieve the stand density. Each set of the NNs consisted of seven individual NNs for all possible combinations of one, two, and three radar wavelengths. Ground and multiple wavelength AIRSAR backscatter data from two ponderosa pine forest stands near Mt. Shasta, California (U.S.A.) were used to evaluate the accuracy of the retrievals. The r.m.s. and relative errors of the retrieval for stand mean dbh were 6.1 cm and 15.6 per cent for one stand (St2), and 3.1 cm and 6.7 per cent for the other stand (St11). The r.m.s. and relative errors of the retrieval for stand density were 71.2 treesha-1 and 23.0 per cent for St2, and 49.7 treesha-1 and 21.3 per cent for St11. (author)

  5. The proactive strategy for sustaining five-needle pine populations: An example of its implementation in the southern Rocky Mountains

    Science.gov (United States)

    A. W. Schoettle; B. A. Goodrich; J. G. Klutsch; K. S. Burns; S. Costello; R. A. Sniezko

    2011-01-01

    The imminent invasion of the non-native fungus, Cronartium ribicola J.C. Fisch., that causes white pine blister rust (WPBR) and the current mountain pine beetle (Dendroctonus ponderosae Hopkins, MPB) epidemic in northern Colorado limber pine forests will severely affect the forest regeneration cycle necessary for functioning ecosystems. The slow growth and maturity of...

  6. Trace elements in fruiting bodies of ectomycorrhizal fungi growing in Scots pine (Pinus sylvestris L.) stands in Poland

    International Nuclear Information System (INIS)

    Rudawska, Maria; Leski, Tomasz

    2005-01-01

    The trace metal contents in fruiting bodies of ectomycorrhizal (ECM) fungi, symbiotic partners of Scots pine, were studied on three sites situated in west-central Poland. Elements were determined by atomic absorption spectrometry in 123 samples of 16 species. The study explored the differences in metal accumulation in relation to site, fungal species, age and part of the fruiting body and results were related to metal content in soil and plant material (roots and needles). Soil analysis revealed that results were obtained under environmental conditions not subject to strong anthropogenic pressure. Median metal concentrations did not differ disparately between sites, although the concentrations of each of the tested metals in the individual species varied to a large extent. Extremely high levels of Al with a large bioconcentration factor (BCF) were found in sporocarps of Thelephora terrestris. The spread between the highest and the lowest concentration (max/min) was very wide in Al, Cd and Pb and these elements may be considered to be absorbed preferentially by fruiting bodies of some species whereas Fe, Mn and Zn, with relatively low values of max/min, are normally absorbed by the majority of fungi. There was no clear relationship between caps and stipes in metal content. However, a tendency to higher metal concentration in the caps was observed. The metal content in young and older fruiting bodies of five different fungi was species dependent. In order to estimate the degree of accumulation of each element by plant and mushrooms, bioconcentration factors (BCFs) were calculated. In plant material (roots and needles), highest values of BCFs were noted for essential metals, like Zn and Mn. Lead showed a definite exclusion pattern (BCF below 1). In fruiting bodies of tested fungi, especially in Amanita muscaria, cadmium was the most intensively accumulated metal. Lead was excluded by plants but was accumulated or excluded by fungi depending on the species. The

  7. Sugar pine seed harvest by Clark's nutcracker: Annual use of a transient resource in Crater Lake National Park, Oregon

    Science.gov (United States)

    Taylor J. Turner; Diana F. Tomback; Bradley Van Anderson; Michael Murray

    2011-01-01

    Clark's nutcrackers (Nucifraga columbiana) are well known for using conifer seeds as their principal nutriment source. Seeds are primarily harvested from whitebark (Pinus albicaulis), piñon (P. edulis), limber (P. flexilis), southwestern white (P. strobiformis), Jeffrey (P. jeffreyi), and ponderosa (P. ponderosa) pine as well as Douglas-fir (Pseudotsuga menziesii...

  8. Strategies for managing whitebark pine in the presence of white pine blister rust [Chapter 17

    Science.gov (United States)

    Raymond J. Hoff; Dennis E. Ferguson; Geral I. McDonald; Robert E. Keane

    2001-01-01

    Whitebark pine (Pinus albicaulis) is one of many North American white pine species (Pinus subgenus Strobus) susceptible to the fungal disease white pine blister rust (Cronartium ribicola). Blister rust has caused severe mortality (often reaching nearly 100 percent) in many stands of white bark pine north of 45° latitude in western North America. The rust is slowly...

  9. The mountain pine beetle and whitebark pine waltz: Has the music changed?

    Science.gov (United States)

    Barbara J. Bentz; Greta Schen-Langenheim

    2007-01-01

    The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae) (MPB), is a bark beetle native to western North American forests, spanning wide latitudinal and elevational gradients. MPB infest and reproduce within the phloem of most Pinus species from northern Baja California in Mexico to central British Columbia in...

  10. Nitrogen cycling following mountain pine beetle disturbance in lodgepole pine forests of Greater Yellowstone

    Science.gov (United States)

    Jacob M. Griffin; Monica G. Turner; Martin Simard

    2011-01-01

    Widespread bark beetle outbreaks are currently affecting multiple conifer forest types throughout western North America, yet many ecosystem-level consequences of this disturbance are poorly understood. We quantified the effect of mountain pine beetle (Dendroctonus ponderosae) outbreak on nitrogen (N) cycling through litter, soil, and vegetation in...

  11. Separating Trends in Whitebark Pine Radial Growth Related to Climate and Mountain Pine Beetle Outbreaks in the Northern Rocky Mountains, USA

    Directory of Open Access Journals (Sweden)

    Saskia L. van de Gevel

    2017-06-01

    Full Text Available Drought and mountain pine beetle (Dendroctonus ponderosae Hopkins outbreaks have affected millions of hectares of high-elevation conifer forests in the Northern Rocky Mountains during the past century. Little research has examined the distinction between mountain pine beetle outbreaks and climatic influence on radial growth in endangered whitebark pine (Pinus albicaulis Engelm. ecosystems. We used a new method to explore divergent periods in whitebark pine radial growth after mountain pine beetle outbreaks across six sites in western Montana. We examined a 100-year history of mountain pine beetle outbreaks and climate relationships in whitebark pine radial growth to distinguish whether monthly climate variables or mountain pine outbreaks were the dominant influence on whitebark pine growth during the 20th century. High mortality of whitebark pines was caused by the overlapping effects of previous and current mountain pine beetle outbreaks and white pine blister rust infection. Wet conditions from precipitation and snowpack melt in the previous summer, current spring, and current summer benefit whitebark pine radial growth during the following growing season. Whitebark pine radial growth and climate relationships were strongest in sites less affected by the mountain pine beetle outbreaks or anthropogenic disturbances. Whitebark pine population resiliency should continue to be monitored as more common periods of drought will make whitebark pines more susceptible to mountain pine beetle attack and to white pine blister rust infection.

  12. Pilot-scale demonstration of SPORL for bioconversion of lodgepole pine to bioethanol and lignosulfonate

    Science.gov (United States)

    Haifeng Zhou; Junyong Zhu; Roland Gleisner; Xueqing Qiu; Eric Horn; Jose Negron

    2016-01-01

    The process sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL) has been the focus of this study. Pilot-scale (50 kg) pretreatment of wood chips of lodgepole pine (Pinus contorta Douglas ex Loudon) killed by mountain pine beetle (Dendroctonus ponderosae Hopkins) were conducted at 165°C...

  13. Running Title: C and N Allocation in Pine; FINAL

    International Nuclear Information System (INIS)

    Ball, J. Timothy

    1996-01-01

    A long standing challenge has been understanding how plants and ecosystems respond to shifts in the balance of resource availabilities. The continuing rise in atmospheric CO(sub 2) will induce changes in the availability and use of several terrestrial ecosystem resources. We report on the acquisition and allocation of carbon and nitrogen in Pinus ponderosa Laws. seedlings grown at three levels of atmospheric carbon dioxide (370, 525, and 700(micro)mol mol(sup -1)) and three levels of soil nitrogen supply in a controlled environment experiment. Nitrogen was applied (0, 100, and 200(micro)g N g soil(sup -1)) at planting and again at week 26 of a 58-week, 4-harvest experiment. At the final harvest, plants grown with variety low available soil nitrogen showed no significant response to atmospheric CO(sub 2). Plants at higher N levels responded positively to CO(sub 2) with the highest biomass at the middle CO(sub 2) level. Plants growing at the lowest N levels immediately allocated a relatively large portion of their nitrogen and biomass to roots. Plants growing at near present ambient CO(sub 2) levels allocated relatively little material to roots when N was abundant but moved both carbon and nitrogen below-ground when N was withheld. Plants growing at higher CO(sub 2) levels, allocated more C and N to roots even when N was abundant, and made only small shifts in allocation patterns when N was no longer supplied. In general, allocation of C and N to roots tended to increase when N supply was restricted and also with increasing atmospheric CO(sub 2) level. These allocation responses were consistent with patterns suggesting a functional balance in the acquisition of above-ground versus below-ground resources. In particular, variation in whole tree average nitrogen concentration can explain 68% of the variation ratio of root biomass to shoot biomass across the harvests. The capability to respond to temporal variation in nutrient conditions, the dynamics of nutrient uptake

  14. A comparison of outbreak dynamics of the spruce bark beetle in Sweden and the mountain pine beetle in Canada (Curculionidae: Scolytinae)

    OpenAIRE

    Kärvemo, Simon; Schroeder, Leif Martin

    2010-01-01

    The European spruce bark beetle (Ips typographus) and the North American mountain pine beetle (Dendroctonus ponderosae) may kill millions of trees during outbreak periods. Both species have also experienced large outbreaks in recent years. But the magnitude of the outbreaks of D. ponderosae is much larger. In this review we compare the outbreak history of I. typographus in Sweden with D. ponderosae in British Columbia in Canada. We also discuss some possible explanations for the difference in...

  15. Abundance and characteristics of lignin liquid intermediates in wood (Pinus ponderosa Dougl. ex Laws.) during hot water extraction

    Science.gov (United States)

    Manuel Raul Pelaez-Samaniego; Vikram Yadama; Manuel Garcia-Perez; Eini Lowell

    2015-01-01

    The objective of this research was to investigate the effects of the conditions of hot water extraction (HWE) on abundance, properties, and structure of lignin depolymerization products. HWE of extracted softwood (ponderosa pine) was conducted using temperatures from 140 to 320°C for 90 min. HWE materials were then subjected to a soxhlet...

  16. Influence of hardwood midstory and pine species on pine bole arthropods

    Science.gov (United States)

    Christopher S. Collins; Richard N. Conner; Daniel Saenz

    2002-01-01

    Arthropod density on the boles of loblolly pines (Pinus taeda) was compared between a stand with and stand without hardwood midstory and between a stand of loblolly and shortleaf pines (P. echinata) in the Stephen E Austin Experimental Forest, Nacogdoches Co., Texas, USA from September 1993 through July 1994. Arthropod density was...

  17. Ash fertilization in a clear cut and in a Scots pine stand in central Sweden. Effects on soil-water and soil chemistry coupled to laboratory leachings of six ash products

    International Nuclear Information System (INIS)

    Ring, Eva; Nohrstedt, H.Oe.; Jansson, Gunnar; Loevgren, Linnea

    1999-01-01

    An experiment with six different ash products was performed in a two-year old clear cut in central Sweden during 1995-98. Two of the ash products were also applied in a nearby 70 year old Scots pine stand. Five of the ash products originated from ash generated by the same boiler. Effects on soil-water and soil chemistry were monitored in the field. The leaching properties of the ash products were tested on the laboratory according to two methods, a column test and a shaking test

  18. Silvicultural treatments for converting loblolly pine to longleaf pine dominance: Effects on planted longleaf pine seedlings

    Science.gov (United States)

    Huifeng Hu; G.Geoff Wang; Joan L. Walker; Benjamin O. Knapp

    2012-01-01

    A field study was installed to test silvicultural treatments for establishing longleaf pine (Pinus palustris Mill) in loblolly pine (P. taeda L.) stands. Harvesting was used to create seven canopy treatments, four with uniformly distributed canopies at different residual basal areas [Control (16.2 m2/ha),...

  19. Harvester Productivity for Row Thinning Loblolly Pine Plantations

    Science.gov (United States)

    James E. Granskog; Walter C. Anderson

    1980-01-01

    Tivo tree harvesters currently being used to thin southern pine plantations were evaluated to determine the effects of stand characteristics on machine productivity. Production rates for row thinning loblolly plantations are presented by stand age, site index, and stand density.

  20. Hybridization Leads to Loss of Genetic Integrity in Shortleaf Pine: Unexpected Consequences of Pine Management and Fire Suppression

    Science.gov (United States)

    Charles G. Tauer; John F. Stewart; Rodney E. Will; Curtis J. Lilly; James M. Guldin; C. Dana Nelson

    2012-01-01

    Hybridization between shortleaf pine and loblolly pine is causing loss of genetic integrity (the tendency of a population to maintain its genotypes over generations) in shortleaf pine, a species already exhibiting dramatic declines due to land-use changes. Recent findings indicate hybridization has increased in shortleaf pine stands from 3% during the 1950s to 45% for...