WorldWideScience

Sample records for pseudotsuga menziesii douglas-fir

  1. Morphology and accumulation of epicuticular wax on needles of Douglas-fir (Pseudotsuga menziesii var. menziesii)

    Science.gov (United States)

    Constance A. Harrington; William C. Carlson

    2015-01-01

    Past studies have documented differences in epicuticular wax among several tree species but little attention has been paid to changes in accumulation of foliar wax that can occur during the year. We sampled current-year needles from the terminal shoots of Douglas-fir (Pseudotsuga menziesii var. menziesii) in late June/early...

  2. Trapping Douglas-fir beetle (Dendroctonus pseudotsugae) with pheromone baited multiple-funnel traps does not reduce Douglas-fir (Pseudotsuga menziesii) mortality

    Science.gov (United States)

    R.A. Progar; N. Sturdevant; M.J. Rinella

    2010-01-01

    Douglas-fir beetle (Dendroctonus pseudotsugae Hopkins) (DFB) causes considerable mortality to Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in western North American forests. We evaluated the use of semiochemical-baited multiple-funnel traps for the protection of small, high-value stands of trees, such as those occurring...

  3. 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...

  4. Effects of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) wood

    Science.gov (United States)

    Xianjun Li; Zhiyong Cai; Qunying Mou; Yiqiang Wu; Yuan Liu

    2011-01-01

    In this study the effect of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) was investigated. Wood specimens were subjected to heat treatment at 160, 180, 200 and 220°C for 1, 2, 3 and 4h. The results show that heat treatment resulted in a darkened color, decreased moisture performance and increased dimensional stability of...

  5. Family differences in equations for predicting biomass and leaf area in Douglas-fir (Pseudotsuga menziesii var. menziesii).

    Science.gov (United States)

    J.B. St. Clair

    1993-01-01

    Logarithmic regression equations were developed to predict component biomass and leaf area for an 18-yr-old genetic test of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco var. menziesii) based on stem diameter or cross-sectional sapwood area. Equations did not differ among open-pollinated families in slope, but intercepts...

  6. Variation in phenology and monoterpene patterns of defoliated and nondefoliated Douglas-fir (Pseudotsuga menziesii var. glauca).

    Science.gov (United States)

    Rose-Marie Muzika; Judith Engle; Catherine Parks; Boyd. Wickman

    1993-01-01

    Foliage was collected from paired Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) trees characterized as either "resistant" or "susceptible" western spruce budworm (Choristoneura occidentalis Freeman (Lepidoptera: Tortricidae) attack. Resistant trees produced more...

  7. Estimation of population structure in coastal Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco var. menziesii] using allozyme and microsatellite markers

    Science.gov (United States)

    Konstantin V. Krutovsky; John Bradley St. Clair; Robert Saich; Valerie D. Hipkins; David B. Neale

    2009-01-01

    Characterizing population structure using neutral markers is an important first step in association genetic studies in order to avoid false associations between phenotypes and genotypes that may arise from nonselective demographic factors. Population structure was studied in a wide sample of approximately 1,300 coastal Douglas-fir [Pseudotsuga menziesii...

  8. Ecological adaptations in Douglas-fir (Pseudotsuga menziesii var. glauca). IV. Montana and Idaho near the Continental Divide

    Science.gov (United States)

    Gerald Rehfeldt

    1988-01-01

    Seventy-seven seedling populations of Douglas-fir (Pseudotsuga menziesii var. glauca) sampled from near the Continental Divide in Idaho and Montana exhibited pronounced genetic differences when compared in three common environments. Differentiation involved several traits that are components of an annual developmental cycle that must be completed within a growing...

  9. The relationship between Swiss needle cast symptom severity and level of Phaeocryptopus gaeumannii colonization in coastal Douglas-fir (Pseudotsuga menziesii var. menziesii).

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    F. Temel; G.R. Johnson; J.K. Stone

    2004-01-01

    This study examined 108 15-year-old Douglas-fir (Pseudotsuga menziesii var. menziesii trees to investigate whether trees exhibiting less severe Swiss needle cast (SNC) symptoms were more resistant (had less fungal colonization) or more tolerant (maintained healthy foliage under similar infection levels). Trees were sampled from...

  10. Deriving Fuel Mass by Size Class in Douglas-fir (Pseudotsuga menziesii Using Terrestrial Laser Scanning

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    Lloyd Queen

    2011-08-01

    Full Text Available Requirements for describing coniferous forests are changing in response to wildfire concerns, bio-energy needs, and climate change interests. At the same time, technology advancements are transforming how forest properties can be measured. Terrestrial Laser Scanning (TLS is yielding promising results for measuring tree biomass parameters that, historically, have required costly destructive sampling and resulted in small sample sizes. Here we investigate whether TLS intensity data can be used to distinguish foliage and small branches (≤0.635 cm diameter; coincident with the one-hour timelag fuel size class from larger branchwood (>0.635 cm in Douglas-fir (Pseudotsuga menziesii branch specimens. We also consider the use of laser density for predicting biomass by size class. Measurements are addressed across multiple ranges and scan angles. Results show TLS capable of distinguishing fine fuels from branches at a threshold of one standard deviation above mean intensity. Additionally, the relationship between return density and biomass is linear by fuel type for fine fuels (r2 = 0.898; SE 22.7% and branchwood (r2 = 0.937; SE 28.9%, as well as for total mass (r2 = 0.940; SE 25.5%. Intensity decays predictably as scan distances increase; however, the range-intensity relationship is best described by an exponential model rather than 1/d2. Scan angle appears to have no systematic effect on fine fuel discrimination, while some differences are observed in density-mass relationships with changing angles due to shadowing.

  11. Growth and morphogenesis of shoot initials of Douglas fir, Pseudotsuga menziesii (Mirb.) Franco, in vitro

    NARCIS (Netherlands)

    Evers, P.W.

    1984-01-01

    An optimalized method of micropropagation of Douglas fir is described. Seasonal changes were found in optima for nitrate and sucrose in the medium and in the optimum for the light intensity during the culture of shoot initials. Differences in morphogenesis were obtained from shoot initials that had

  12. Temporal dynamics of tree source water in sky island ecosystems with ephemeral snow pack: a case study using Pseudotsuga menziesii (Douglas Fir)

    Science.gov (United States)

    Papuga, S. A.; Hamann, L.

    2017-12-01

    In semiarid regions, such as the desert southwest, water is a scarce resource that demands careful attention to its movement throughout the environment for accurate accounting in regional water budgets. Ephemeral snow pack in sky island ecosystems delivers a large fraction of the water resources to communities lower in the watershed. Because the major source of loss to those water resources is evapotranspiration (ET), any change in ET in these ecosystems will have major implications downstream. Climate scientists predict more intense and less frequent precipitation events in the desert southwest, which will alter the existing soil-plant-atmosphere continuum (SPAC). Therefore, understanding how water currently moves within that continuum is imperative in preparing for these predicted changes. This study used stable isotopes (δ18O and δD) to study the SPAC that exists in the Santa Catalina Mountain Critical Zone Observatory (SCM-CZO) to determine where the dominant tree species (Pseudotsuga menziesii, a.k.a., Douglas Fir) retrieves its water from and whether that source varies with season. We hypothesize that the Douglas Fir uses shallow soil water (season and deeper soil water (> 40 cm) during the snowmelt season. The findings of this work will help to better account for water losses due to ET and the movement of water throughout the environment. With a shift in the SPAC dynamics, the Douglas Fir may become increasingly water stressed effecting its ability to survive in the desert southwest which will have important consequences for water resources in this region.

  13. Effects of Harvesting Systems and Bole Moisture Loss on Weight Scaling of Douglas-Fir Sawlogs (Pseudotsuga Menziesii var. glauca Franco

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    Jarred D. Saralecos

    2014-09-01

    Full Text Available Characterizing the moisture loss from felled trees is essential for determining weight-to-volume (W-V relationships in softwood sawlogs. Several factors affect moisture loss, but research to quantify the effects of bole size and harvest method is limited. This study was designed to test whether bole size, harvest method, environmental factors, and the associated changes in stem moisture content of felled Douglas-fir (Pseudotsuga menziesii var. glauca Franco affected the weight-to-volume relationship of sawlogs. Thirty trees in three size classes (12.7–25.4 cm, 25.5–38.1 cm, 38.2–50.8 cm were felled and treated with one of two harvesting processing methods. Moisture content was sampled every two days for four weeks. Results showed 6% greater moisture loss in the crowns of stems that retained limbs after felling compared to stems with limbs removed after harvesting. Additionally, moisture loss rate increased as stem size decreased. The smallest size class lost 58% moisture content compared to 34% in the largest size class throughout the study duration. These stem moisture content changes showed a 17% reduction in average sawlog weight within the largest size class, shifting current W-V relationships from 2.33 tons m−3 to 1.94 tons m−3 during the third seasonal quarter for northern Idaho Douglas-fir and potentially altering relationships year-round.

  14. Bordered pit structure and function determine spatial patterns of air-seeding thresholds in xylem of Douglas-fir (Pseudotsuga menziesii; Pinaceae) trees.

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    J.C. Domec; B. Lachenbruch; F.C. Meinzer

    2006-01-01

    The air-seeding hypothesis predicts that xylem embolism resistance is linked directly to bordered pit functioning. We tested this prediction in trunks, roots, and branches at different vertical and radial locations in young and old trees of Pseudotsuga menziesii. Dimensions of bordered pits were measured from light and scanning electron micrographs...

  15. Species effect on the water use efficiency of a mixed forest of beech (Fagus sylvatica L.), Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) and silver fir (Abies alba Mill.) in Belgium Ardennes.

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    Soubie, Rémy; Heinesch, Bernard; Aubinet, Marc; Vincke, Caroline

    2010-05-01

    Induced by climate change, intensity and frequency of droughts should be more important for the next century. How does water availability affect the physiology of woody plants at the species and stand scale? Carbon and water vapour fluxes measurements of a mixed forest (deciduous and coniferous) were performed for over ten years by the eddy covariance method in Belgian Ardennes (Aubinet et al, 2001) as a part of the CarboEurope project. Whereas carbon fluxes have been analyzed in detailed and good estimations of the Net Ecosystem Exchange (NEE) and Gross Primary Production (GPP) were obtained, a thorough analysis of water vapour fluxes remains to be done. Improving analysis of water vapour fluxes and monitoring species transpiration will contribute to the estimation of the water use efficiency, WUE, at both the species and stand scale. The WUE well characterizes the vegetation productivity and ecosystem response to environmental factors. It also allows evaluating the sensitivity of temperate woody species to drought. The species concerned are beech (Fagus sylvatica L.), Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) and silver fir (Abies alba Mill.). Since summer 2009 we monitor and analyze each species water use by measuring sap flow with the thermal dissipation method (Granier, 1987). Results at the species level will then be upscaled and compared to stand water vapour fluxes measurements obtained by the eddy covariance methodology. Transpiration of each species will be analyzed in relation with their own phenological and ecophysiological attributes, ecosystem soil and atmospheric conditions, to clarify among others their behaviour in case of water deficit. Data are actually analysed, the presented results will concern the 2009, and a part of 2010 growing season.

  16. Effect of environmental and cultural conditions on medium pH and explant growth performance of Douglas-fir (Pseudotsuga menziesii shoot cultures [version 2; referees: 2 approved

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    Chien-Chih Chen

    2015-05-01

    Full Text Available The medium pH level of plant tissue cultures has been shown to be essential to many aspects of explant development and growth. Sensitivity or tolerance of medium pH change in vitro varies according to specific requirements of individual species. The objectives of this study are to 1 determine medium pH change over time in storage conditions and with presence of explants, 2 evaluate the effects of medium pH change on explant growth performance and 3 assess the effects of adding a pH stabilizer, 2-(N-morpholinoethanesulfonic acid (MES that is commonly used in Douglas-fir micropropagation medium. Vegetative buds were collected in the spring before breaking dormancy from juvenile and mature donor trees for conducting these evaluations. Medium, with or without MES, was pre-adjusted to five pH levels before adding MES, agar and autoclaving. Medium pH changes and explant growth parameters were measured at eight different incubation times. Overall, MES provided a more stable medium pH, relative to starting pH values, under both light and dark storage conditions as well as with presence of explants. A general trend of decreasing medium pH over time was found comparing explants from juvenile and mature donor genotypes. Explant height and weight growth increased over time, but differ among explants from juvenile and mature donor genotypes. Our findings suggest that a 21-day subculture practice may best sustain medium freshness, medium pH level and desirable explant growth.

  17. 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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    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...

  18. Graft union formation in Douglas-fir.

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    D.L. Copes

    1969-01-01

    Greenhouse-grown Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) graft unions were examined between 2 and 84 days after grafting. Room temperature was maintained at 60-70 F throughout the growing season. In most respects grafts of Douglas-fir followed development patterns previously reported for spruce and pine grafts, but specific differences...

  19. Flight periodicity of the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins (Coleoptera: Curculionidae: Scolytinae) in Colorado, U.S.A

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    Jose F. Negron; Willis C. Schaupp; Lee Pederson

    2011-01-01

    There are about 500 species of bark beetles (Coleoptera: Curculionidae: Scolytinae) in the United States (Wood 1982). A number of them are important disturbance agents in forested ecosystems, occasionally creating large tracts of dead trees. One eruptive species is the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, which utilizes Douglas-fir, Pseudotsuga...

  20. Size of Douglas-fir trees in relation to distance from a mixed red alder - Douglas-fir stand

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    R.E. Miller; D.L. Reukema; T.A. Max

    1993-01-01

    Variation in diameter, height, and stem volume of 57-year-old Douglas-fir(Pseudotsuga menziesii var. menziesii (Mirb.) Franco) was related to distance of these trees from a 27 m wide strip in the same Douglas-fir plantation that had been interplanted with red alder (Alnus rubra Bong.). Within the...

  1. NEEDLE ANATOMY CHANGES WITH INCREASING TREE AGE IN DOUGLAS FIR

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    Morphological differences between old growth and sapling (Pseudotsuga menziesii, (Mirb.) Franco) Douglas fir trees may extend to differences in needle anatomy. We used microscopy with image analysis to compare and quantify anatomical parameters in cross-sections of previous year...

  2. Belowground competition from overstory trees influences Douglas-fir sapling morphology in thinned stands

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    Warren D. Devine; Timothy B. Harrington

    2009-01-01

    We evaluated effects of belowground competition on morphology of naturally established coast Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) saplings in 60- to 80-year-old thinned Douglas-fir stands in southwestern Washington. We separately quantified belowground competition from overstory and understory sources...

  3. Stocktype and vegetative competition influences on Pseudotsuga menziesii and Larix occidentalis seedling establishment

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    Jeremiah R. Pinto; Bridget A. McNassar; Olga A. Kildisheva; Anthony S. Davis

    2018-01-01

    Douglas fir (Pseudotsuga menziesii var. glauca (Mayr) Franco), and western larch (Larix occidentalis Nutt.) are species of ecological and commercial importance that occur throughout the Western United States. Effective reforestation of these species relies on successful seedling establishment, which is affected by planting stock quality, stocktype size, and...

  4. Flavonoids from Pseudotsuga menziesii.

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    Krauze-Baranowska, Mirosława; Sowiński, Paweł; Kawiak, Anna; Sparzak, Barbara

    2013-01-01

    Four O-acylated flavonol glycosides, new in the plant kingdom, were isolated from the needles of Pseudotsuga menziesii. Their structures were established by 1D and 2D NMR and MS data as: daglesioside I [kaempferol 3-O-[2",5"-O-(4''',4(IV)-dihydroxy)-beta-truxinoyl]-alpha-L-arabinofuranoside] (1), daglesioside II [kaempferol 3-O-[2",5"-O-(4"'-hydroxy)-beta-truxinoyl]-alpha-L-arabinofuranoside] (2), daglesioside III [kaempferol 3-O-[2",5"-di-O-(E)-p-coumaroyl]-alpha-L-arabinofuranoside] (3), and daglesioside IV [kaempferol 3-O-[3",6"-di-O-(E)-cinnamoyl]-beta-D-glucopyranoside] (4). In addition, the known flavonoids (E)-tiliroside, (E)-ditiliroside, astragalin (kaempferol 3-O-beta-D-glucopyranoside), isorhamnetin, kaempferol, and quercetin were identified. The cytotoxic activity of compounds 1 and 3 was evaluated towards the HL-60, HeLa, and MDA-MB468 cell lines.

  5. 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.

  6. Douglas-fir displays a range of growth responses to temperature, water, and Swiss needle cast in western Oregon, USA

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    Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) growth in the Pacific Northwest is affected by climatic, edaphic factors and Swiss needle cast (SNC) disease. We examine Douglas-fir growth responses to temperature, dewpoint deficit (DPD), soil moisture, and SNC ...

  7. Growth of bear-damaged trees in a mixed plantation of Douglas-fir and red alder.

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    Richard E. Miller; Harry W. Anderson; Donald L. Reukema; Timothy A. Max

    2007-01-01

    Incidence and effects of tree damage by black bear (Ursus americanus altifrontalis) in a 50-year-old, coast Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) plantation are described. Bears girdled or partially girdled 35 dominant or codominant Douglas-fir trees per acre, but only in that...

  8. Projected future suitable habitat and productivity of Douglas-fir in western North America

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    Aaron R. Weiskittel; Nicholas L. Crookston; Gerald E. Rehfeldt

    2012-01-01

    Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) is one of the most common and commercially important species in western North America. The species can occupy a range of habitats, is long-lived (up to 500 years), and highly productive. However, the future of Douglas-fir in western North America is highly uncertain due to the expected changes in climate conditions....

  9. Multi-decadal establishment for single-cohort Douglas-fir forests

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    James A. Freund; Jerry F. Franklin; Andrew J. Larson; James A. Lutz

    2014-01-01

    The rate at which trees regenerate following stand-replacing wildfire is an important but poorly understood process in the multi-century development of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) forests. Temporal patterns of Douglas-fir establishment reconstructed from old-growth forests (>450 year) have...

  10. Natural regeneration of Douglas-fir and associated species using modified clear-cutting systems in the Oregon Cascades.

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    Jerry F. Franklin

    1963-01-01

    Clear cutting is the standard harvesting system in old-growth Douglas-fir (Pseudotsuga menziesii) forests in the Pacific Northwest. Usually these clear cuts are in "staggered settings" of 15 to 80 acres with the surrounding stand left uncut to provide seed and serve as a firebreak. However, satisfactory natural regeneration of Douglas-fir...

  11. Changes in wood product proportions in the Douglas-fir region with respect to size, age, and time.

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    R.A. Monserud; X. Zhou

    2007-01-01

    We examine both the variation and the changing proportions of different wood products obtained from trees and logs in the Douglas-fir region of the Northwestern United States. Analyses are based on a large product recovery database covering over 40 years of recovery studies; 13 studies are available for Douglas-fir (Pseudotsuga menziesii (Mirb.)...

  12. An examination of the genetic control of Douglas-fir vascular tissue phytochemicals: implications for black bear foraging.

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    Bruce A. Kimball; G.R. Johnson; Dale L. Nolte; Doreen L. Griffin

    1999-01-01

    Silvicultural practices can influence black bear (Ursus americanus) foraging preferences for Douglas-fir (Pseudotsuga menziesii) cambial-zone vascular tissues, but little is known about the role of genetics. To study the impact of genetic selection, vascular tissue samples were collected from Douglas-fir trees in six half-sib families from five...

  13. Basal area growth, carbon isotope discrimination, and intrinsic water use efficiency after fertilization of Douglas-fir in the Oregon Coast Range

    Science.gov (United States)

    Many hectares of intensively managed Douglas-fir (Pseudotsuga menziesii Mirb. Franco) stands in western North America are fertilized with nitrogen to increase growth rates. Understanding the mechanisms of response facilitates prioritization of stands for treatment. The objective ...

  14. Developmental decline in height growth in Douglas-fir.

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    Barbara J. Bond; Nicole M. Czarnomski; Clifton Cooper; Michael E. Day; Michael S. Greenwood

    2007-01-01

    The characteristic decline in height growth that occurs over a tree's lifespan is often called "age-related decline." But is the reduction in height growth in aging trees a function of age or of size? We grafted shoot tips across different ages and sizes of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees to determine whether...

  15. Effects of bear damage on Douglas-fir lumber recovery

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    Eini C. Lowell; Dennis Dykstra; George McFadden

    2009-01-01

    Bear activily resulting in injury to Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) trees has been documented as early as the mid-1850s in the Pacific Northwest. The study reported in this article was designed to help managers decide whether the common practice of removing the damaged but potentially valuable butt section of the bottom log and...

  16. Tree-ring stable isotopes record the impact of a foliar fungal pathogen on CO2 assimilation and growth in Douglas-fir

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    Swiss needle cast (SNC) is a fungal disease of Douglas-fir (Pseudotsuga menziesii) that has recently become prevalent in coastal areas of the Pacific Northwest. We used growth measurements and stable isotopes of carbon and oxygen in tree-rings of Douglas-fir and a non-susceptible...

  17. Geographical Variation in the Terpene Composition of the Leaf Oil of Douglas Fir,

    Science.gov (United States)

    The two forms of Douglas fir, Pseudotsuga menziesii var. menziesii and var. glauca, differ quite considerably with regard to the monoterpenes of...their leaf oils. Several chemical races, differing quantitatively in certain monoterpenes , appear to exist in each variety and the leaf oil composition seems to be particularly useful in classifying intermediate forms. (Author)

  18. Stump-to-truck cable logging cost equations for young-growth douglas-fir

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    Chris B. LeDoux; Roger D. Fight; Tom L. Ortman

    1986-01-01

    Logging cost simulators and data from logging cost studies have been assembled and converted into a series of equations that can be used to estimate the cost of logging young-growth coastal Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco var. menziesii) in mountainous terrain of the Pacific Northwest. These equations were...

  19. The Douglas-fir genome sequence reveals specialization of the photosynthetic apparatus in Pinaceae

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    David B. Neale; Patrick E. McGuire; Nicholas C. Wheeler; Kristian A. Stevens; Marc W. Crepeau; Charis Cardeno; Aleksey V. Zimin; Daniela Puiu; Geo M. Pertea; U. Uzay Sezen; Claudio Casola; Tomasz E. Koralewski; Robin Paul; Daniel Gonzalez-Ibeas; Sumaira Zaman; Richard Cronn; Mark Yandell; Carson Holt; Charles H. Langley; James A. Yorke; Steven L. Salzberg; Jill L. Wegrzyn

    2017-01-01

    A reference genome sequence for Pseudotsuga menziesii var. menziesii (Mirb.) Franco (Coastal Douglas-fir) is reported, thus providing a reference sequence for a third genus of the family Pinaceae. The contiguity and quality of the genome assembly far exceeds that of other conifer reference genome sequences (contig N50 = 44,136 bp and scaffold N50...

  20. DFSIM with economics: A financial analysis option for the DFSIM Douglas-fir simulator.

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    Roger O. Fight; Judith M. Chittester; Gary W. Clendenen

    1984-01-01

    A modified version of the DFSIM Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) growth and yield simulator, DFSIM WITH ECONOMICS, now has an economics option that allows the user to estimate present net worth at the same time a silvicultural regime is simulated. If desired, the economics option will apply a...

  1. Realized gains from block-plot coastal Douglas-fir trials in the northern Oregon Cascades

    Science.gov (United States)

    Terrence Z. Ye; Keith J.S. Jayawickrama; J. Bradley. St. Clair

    2010-01-01

    Realized gains for coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) were evaluated using data collected from 15-year-old trees from five field trials planted in large block plots in the northern Oregon Cascades. Three populations with different genetic levels (elite--high predicted gain; intermediate--moderate predicted gain; and an...

  2. Inheritance of restriction fragment length polymorphisms, random amplified polymorphic DNAs and isozymes in coastal Douglas-fir

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    K.D. Jermstad; A.M. Reem; J.R. Henifin; N.C. Wheeler; D.B Neale

    1994-01-01

    A total of 225 new genetic loci [151 restriction fragment length polymorphisms (RFLP) and 74 random amplified polymorphic DNAs (RAPD)] in coastal Douglas- fir [Pseudotsuga menziesii (Mirb.) Franco var. menziesii] have been identified using a three-generation outbred pedigree. The Mendelian inheritance of 16 RFLP loci and 29...

  3. Growth of Douglas-fir near equipment trails used for commercial thinning in the Oregon Coast Range.

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    Richard E. Miller; Jim Smith; Paul W. Adams; Harry W. Anderson

    2007-01-01

    Soil disturbance is a visually apparent result of using heavy equipment to harvest trees. Subsequent consequences for growth of remaining trees, however, are variable and seldom quantified. We measured tree growth 7 and 11 years after thinning of trees in four stands of coast Douglas-fir (Pseudotsuga menziesii var. menziesii(...

  4. Detecting response of Douglas-fir plantations to urea fertilizer at three locations in the Oregon Coast Range.

    Science.gov (United States)

    Richard E. Miller; Jim Smith; Harry. Anderson

    2001-01-01

    Fertilizer trials in coast Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) in the Oregon Coast Range usually indicate small and statistically nonsignificant response to nitrogen (N) fertilizers. Inherently weak experimental designs of past trials could make them too insensitive to detect growth differences...

  5. Effects of formaldehyde-enriched mists on Pseudotsuga menziesii (Mirbel) Franco and Lobaria pulmonaria (L.) Hoffm.

    Science.gov (United States)

    Muir, P S; Shirazi, A M

    1996-01-01

    The atmosphere in some areas is polluted with formaldehyde (HCHO); however, little is known about effects of HCHO on plants at concentrations resembling those in polluted areas. The effects of simulated fogwater enriched with HCHO on seedlings of Pseudotsuga menziesii (Mirbel) Franco (Douglas fir) and pendants of Lobaria pulmonaria (L.) Hoffm. were assessed. Plants were treated with HCHO-enriched fog (target concentrations of 100, 500, and 1000 microm) during five 4-night mist sessions. Growth and nitrogenase activity (acetylene reduction rate) for lichens and growth and timing of bud-break for Douglas fir were monitored. Nitrogenase activity was lowest in lichens treated at the highest HCHO concentration after all but the first mist session, and it declined significantly with increasing HCHO concentration after the final mist session (R(2) = 0.60, p = 0.02). However, differences in nitrogenase activity among treatments were generally not statistically significant (most p values from ANOVAs were >/= 0.20). Formaldehyde did not affect growth of the lichens. Budbreak of Douglas firs was slightly delayed and height growth was slightly depressed with increasing HCHO concentration, although effects were not statistically significant.

  6. La Pseudotsuga menziesii en Guipúzcoa

    OpenAIRE

    Aunós Gómez, Álvaro

    1988-01-01

    Se describe el comportamiento de la "Pseudotsuga menziesii" en la provincia de Guipúzcoa, analizándose su evolución y las respuestas de esas masas a los tratamientos culturales practicados. Por último, se ofrecen unas orientaciones sobre la selvicultura a aplicar. On décrit les comportement de la "Pseudotsuga menziesii" dans la province de Guipúzcoa, en analysant son évolution et les réponses de ces masses aux traitements culturels practiqués. Finalement, on propose des orientations sur la...

  7. Wood Anatomy and Insect Defoliator Systems: Is there an anatomical response to sustained feeding by the western spruce budworm (Choristoneura occidentalis) on Douglas-fir (Pseudotusga menziesii)?

    Science.gov (United States)

    Axelson, Jodi; Gärtner, Holger; Alfaro, René; Smith, Dan

    2013-04-01

    The western spruce budworm (Choristoneura occidentalis Freeman) is the most widespread and destructive defoliator of coniferous forests in western North America, and has a long-term coexistence with its primary host tree, Douglas-fir (Pseudotsuga menziesii Franco). Western spruce budworm (WSB) outbreaks usually last for several years, and cause reductions in annual growth, stem defects, and regeneration delays. In British Columbia, the WSB is the second most damaging insect after the mountain pine beetle, and sustained and/or severe defoliation can result in the mortality of host trees. Numerous studies have used tree rings to reconstruct WSB outbreaks across long temporal scales, to evaluate losses in stand productivity, and examine isotope ratios. Although some studies have looked at the impacts of artificial defoliation on balsam fir in eastern North America, there has been no prior research on how WSB outbreaks affect the anatomical structure of the stem as described by intra-annual wood density and potential cell size variations. The objective of this study was to anatomically examine the response of Douglas-fir to sustained WSB outbreaks in two regions of southern British Columbia. We hypothesize that the anatomical intra-annual characteristics of the tree rings, such as cell wall thickness, latewood cell size, and/or lumen area changes during sustained WSB outbreaks. To test this hypothesis we sampled four permanent sample plots in coastal and dry interior sites, which had annually resolved defoliation data collected over a 7-12 year period. At each site diameter-at-breast height (cm), height (m), and crown position were recorded and three increment cores were extracted from 25 trees. Increment cores were prepared to permit anatomical and x-ray density analyses. For each tree, a 15µm thick micro section was cut from the radial plane. Digital images of the micro sections were captured and processed. In each annual ring, features such as cell lumen area (µm2

  8. 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.

  9. Regeneration in mixed conifer and Douglas-fir shelterwood cuttings in the Cascade Range of Washington.

    Science.gov (United States)

    K.W. Seidel

    1983-01-01

    A survey of shelterwood cuttings in mixed conifer and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests in the Cascade Range in Washington showed that, on the average, shelterwood units were adequately-stocked with a mixture of advance, natural postharvest, and planted reproduction of a number of species. Shelterwood cuttings in the...

  10. Dynamic phenotypic plasticity in photosynthesis and biomass patterns in Douglas-fir seedlings

    Science.gov (United States)

    A. C. Koehn; G. I. McDonald; D. L. Turner; D. L. Adams

    2010-01-01

    As climate changes, understanding the mechanisms long-lived conifers use to adapt becomes more important. Light gradients within a forest stand vary constantly with the changes in climate, and the minimum light required for survival plays a major role in plant community dynamics. This study focuses on the dynamic plasticity of Douglas-fir (Pseudotsuga menziesii var....

  11. Physiological responses of planting frozen and thawed Douglas-fir seedlings

    Science.gov (United States)

    M. Anisul Islam; Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese

    2008-01-01

    We studied the short-term (7-day) physiological responses of planting thawed and frozen root plugs of Douglas-fir (Pseudotsuga menziesii) seedlings in 2 separate experiments under cool-moist and warm-dry growing conditions, respectively. Our results showed that shoot water potential, root hydraulic conductance, net photosynthesis (A), and...

  12. Early genetic evaluation of open-pollinated Douglas-fir families

    Science.gov (United States)

    Kurt H. Riitters; David A. Perry

    1987-01-01

    In a test of early genetic evaluation of the growth potential of 14 families of open-pollinated Douglas-fir (Pseudotsuga menziesii) [Mirb.] Franco), measures of growth and phenology of seedligns grown in a coldframe were correlated with height of saplings in evaluation plantations at 9, 12, and 15 years. fifteen-year height was most strongly...

  13. Ground-based forest harvesting effects on soil physical properties and Douglas-fir growth.

    Science.gov (United States)

    Adrian Ares; Thomas A. Terry; Richard E. Miller; Harry W. Anderson; Barry L. Flaming

    2005-01-01

    Soil properties and forest productivity can be affected by heavy equipment used for harvest and site preparation but these impacts vary greatly with site conditions and operational practices. We assessed the effects of ground-based logging on soil physical properties and subsequent Douglas-fir [Pseudotsuga menziesii (Mirb) Franco] growth on a highly...

  14. Estimating tree biomass, carbon, and nitrogen in two vegetation control treatments in an 11-year-old Douglas-fir plantation on a highly productive site

    Science.gov (United States)

    Warren D. Devine; Paul W. Footen; Robert B. Harrison; Thomas A. Terry; Constance A. Harrington; Scott M. Holub; Peter J. Gould

    2013-01-01

    We sampled trees grown with and without competing vegetation control in an 11-year-old Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) plantation on a highly productive site in southwestern Washington to create diameter based allometric equations for estimating individual-tree bole, branch, foliar, and total...

  15. Pruning high-value Douglas-fir can reduce dwarf mistletoe severity and increase longevity in Central Oregon

    Science.gov (United States)

    Helen M. Maffei; Gregory M. Filip; Nancy E. Grulke; Brent W. Oblinger; Ellis Q. Margolis; Kristen L. Chadwick

    2016-01-01

    Mid- to very large-sized Douglas-fir (Pseudotsuga menzieseii var. menziesii) that were lightly- to moderately-infected by dwarf mistletoe (Arceuthobium douglasii) were analyzed over a 14-year period to evaluate whether mechanical pruning could eradicate mistletoe (or at least delay the onset of severe infection) without...

  16. Occurrence of shrubs and herbaceous vegetation after clear cutting old-growth Douglas-fir in the Oregon Cascades.

    Science.gov (United States)

    Vern P. Yerkes

    1960-01-01

    Land managers often express a need for more complete information about the vegetative cover that develops on cutover areas between harvest of old-growth Douglas-fir (Pseudotsuga menziesii) and establishment of a young-growth forest. The composition and density of this cover frequently determines the management techniques that must be used to...

  17. Levels-of-growing-stock cooperative study in Douglas-fir: report no. 18--Rocky Brook, 1963-2006.

    Science.gov (United States)

    Robert O. Curtis; David D. Marshall

    2009-01-01

    This report documents the history and results of the Rocky Brook installation of the cooperative levels-of-growing-stock (LOGS) study in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), over the 41-year period 1965 to 2006. This 1938 plantation is one of the two site-IV installations among the nine installations in the study. Much public...

  18. History of fire and Douglas-fir establishment in a savanna and sagebrush-grassland mosaic, southwestern Montana, USA

    Science.gov (United States)

    Emily K. Heyerdahl; Richard F. Miller; Russell A. Parsons

    2006-01-01

    Over the past century, trees have encroached into grass- and shrublands across western North America. These include Douglas-fir trees (Pseudotsuga menziesii (Mirb.) Franco var. glauca (Beissn.) Franco) encroaching into mountain big sagebrush Nutt. ssp. vaseyana (Rydb.) Beetle) from stable islands of savanna in...

  19. Height-growth response to climatic changes differs among populations of Douglas-fir: A novel analysis of historic data

    Science.gov (United States)

    Laura P. Leites; Andrew P. Robinson; Gerald E. Rehfeldt; John D. Marshall; Nicholas L. Crookston

    2012-01-01

    Projected climate change will affect existing forests, as substantial changes are predicted to occur during their life spans. Species that have ample intraspecific genetic differentiation, such as Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), are expected to display population-specific growth responses to climate change. Using a mixed-effects modeling approach,...

  20. Spatial and population characteristics of dwarf mistletoe infected trees in an old-growth Douglas-fir - western hemlock forest.

    Science.gov (United States)

    David C. Shaw; Jiquan Chen; Elizabeth A. Freeman; David M. Braun

    2005-01-01

    We investigated the distribution and severity of trees infected with western hemlock dwarf mistletoe (Arceuthobium tsugense (Rosendahl) G.N. Jones subsp. tsugense) in an old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) - western hemlock (Tsuga heterophylla (Raf.) Sarg.)...

  1. The influence of weather variation on regional growth of Douglas-fir stands in the U.S. Pacific Northwest.

    Science.gov (United States)

    Charles E. Peterson; Linda S. Heath

    1991-01-01

    In this paper we examine the influence of precipitation and temperature deviations on regional volume growth rates in even aged, onnen.,ed second growth Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) stands. Between 1969 and 1986, average volume growth rates in natural stands of coast Douglas fix in western Washington and Oregon were negatively...

  2. Symptoms associated with inoculation of stems on living Douglas-fir and Grand Fir Trees with Phytophthora ramorum

    Science.gov (United States)

    Gary Chastagner; Kathy Riley; Katie Coats; Marianne Elliott; Annie DeBauw; Norm Dart

    2010-01-01

    To obtain a better understanding of the potential risk of infection and colonization of living Douglas-fir (Pseudotsuga menziesii) and grand fir (Abies grandis) stems, the stems on over 150 trees of each species were inoculated at a Christmas tree farm near Los Gatos, California. This study had the following objectives: 1)...

  3. Fine-scale variability in growth-climate relationships of Douglas-fir, North Cascade Range, Washington.

    Science.gov (United States)

    Michael J. Case; David L. Peterson

    2005-01-01

    Information about the sensitivity to climate of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) is valuable because it will allow forest managers to maximize growth, better understand how carbon sequestration may change over time, and better model and predict future ecosystem responses to climatic change. We examined the effects of climatic...

  4. Relationships among chilling hours, photoperiod, calendar date, cold hardiness, seed source, and storage of Douglas-fir seedlings

    Science.gov (United States)

    Diane L. Haase; Nabil Khadduri; Euan Mason; Kas Dumroese

    2016-01-01

    Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) seedlings from three nurseries in the Pacific Northwest United States were lifted on five dates from mid-October through mid-December 2006. Each nursery provided seedlings from a low- and a high-elevation seed lot. Photoperiod and accumulated chilling hours (calculated using two methods) were evaluated...

  5. Identification of varieties and gene flow in Douglas fir exemplified in artificially established stands in Germany

    Directory of Open Access Journals (Sweden)

    Barbara Fussi

    2013-12-01

    Full Text Available Douglas-fir [Pseudotsuga menziesii (Mirb. Franco] is an economically valuable non-native tree species in Germany and is considered very promising in view of global climate change. Therefore, the genetic characterization of Douglas-fir populations and seed stands in Germany is essential. We studied coastal and interior Douglas-fir varieties, both present in Germany, by using eleven isoenzyme and four microsatellite loci. By analyzing eight reference populations of known origin we were able to identify the two varieties on the population level using Bayesian and distance based methods. Seven populations present in Bavaria were then successfully assigned to one of the two varieties. Within varieties we found stronger grouping within the interior variety than within the coastal one. Despite lower differences within coastal Douglas-fir we have first indications for the origin of two populations. For two Bavarian populations, natural regeneration was included and genetic data revealed no significant genetic difference between adults and offspring. The parentage analysis for one of the studied stands revealed that a large proportion of adults took part in the reproduction, but some trees were more successful than others in transferring their genes to the next generation. Our study was able to improve variety identification of Douglas-fir using isoenzyme markers and nuclear microsatellites and study reproductive patterns, both are important issues for the management of Douglas-fir stands in Bavaria.

  6. Residual densities affect growth of overstory trees and planted Douglas-fir, western hemlock, and western redcedar: results from the first decade

    Science.gov (United States)

    Leslie Chandler Brodie; Dean S. DeBell

    2013-01-01

    In recent years, interest has increased in silvicultural systems and harvest cuts that retain partial overstories, but there are few data available on the growth of the understory trees in such stands. We studied the response of overstory trees and underplanted seedlings, Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga...

  7. Tree microhabitat structures as indicators of biodiversity in Douglas-fir forests of different stand ages and management histories in the Pacific Northwest, U.S.A.

    Science.gov (United States)

    Alexa K. Michel; Susanne. Winter

    2009-01-01

    In this study, microhabitat structures in Douglas-fir (Pseudotsuga menziesii) forests were defined and their frequency and abundance in natural stands and stands of varying active management histories and stand ages was compared. Indicator microhabitat structures for natural forests were determined and the relationship of the abundance of...

  8. Levels-of-growing-stock cooperative study in Douglas-fir: report no. 19—The Iron Creek study, 1966–2006.

    Science.gov (United States)

    Robert O. Curtis; David D. Marshall

    2009-01-01

    This report documents the history and results of the Iron Creek installation of the cooperative Levels-of-Growing-Stock (LOGS) study in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), over the period 1966–2006 (ages 19 to 59). This is a 1949 plantation on an excellent site, and is one of nine installations in the study. Results are generally...

  9. Growth and yield of all-aged Douglas-fir -- western hemlock forest stands: a matrix model with stand diversity effects.

    Science.gov (United States)

    Jingjing Liang; Joseph Buonglorno; Robert A. Monserud

    2005-01-01

    A density-dependent matrix model was developed for Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) -- western hemlock (Tsuga heterophylla (Raf.) Sarg.) forest stands in the Pacific Northwest of the United States. The model predicted the number and volume of trees for 4 species groups and 19 diameter classes. The parameters...

  10. Stand-level gas-exchange responses to seasonal drought in very young versus old Douglas-fir forests of the Pacific Northwest, USA

    Science.gov (United States)

    Sonia Wharton; Matt Schroeder; Ken Bible; Matthias Falk; Kyaw Tha Paw U

    2009-01-01

    This study examines how stand age affects ecosystem mass and energy exchange response to seasonal drought in three adjacent Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests. The sites include two early seral (ES) stands (0 to 15 years old) and an old-growth (OG) (~450 to 500 years old) forest in the Wind River Experimental Forest,...

  11. THE KINETICS OF NH(4)+ AND NO3(-) UPTAKE BY DOUGLAS-FIR FROM SINGLE N-SOLUTIONS AND FROM SOLUTIONS CONTAINING BOTH NH(4)+ AND NO3(-)

    NARCIS (Netherlands)

    KAMMINGAVANWIJK, C; PRINS, HBA

    The kinetics of NH4+ and NO3- uptake in young Douglas fir trees (Pseudotsuga menziesii [Mirb.] Franco) were studied in solutions, containing either one or both N species. Using solutions containing a single N species, the V(max) of NH4+ uptake was higher than that of NO3- uptake. The K(m) of NH4+

  12. ELEVATED CO2 AND ELEVATED TEMPERATURE HAVE NO EFFECT ON DOUGLAS-FIR FINE-ROOT DYNAMICS IN NITROGEN-POOR SOIL

    Science.gov (United States)

    Here, we investigate fine-root production, mortality and standing crop of Douglas-fir (Pseudotsuga menziesii) seedlings exposed to elevated atmospheric CO2 and elevated air temperature. We hypothesized that these treatments would increase fine-root production, but that mortality ...

  13. Soil disturbance and 10-year growth response of coast Douglas-fir on nontilled and tilled skid trails in the Oregon Cascades.

    Science.gov (United States)

    Ronald Heninger; William Scott; Alex Dobkowski; Richard Miller; Harry Anderson; Steve Duke

    2002-01-01

    We (i) quantified effects of skidder yarding on soil properties and seedling growth in a portion of western Oregon, (ii) determined if tilling skid trails improved tree growth, and (iii) compared results with those from an earlier investigation in coastal Washington. Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were hand planted at...

  14. Douglas-fir displays a range of growth responses to ...

    Science.gov (United States)

    Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) growth in the Pacific Northwest is affected by climatic, edaphic factors and Swiss needle cast (SNC) disease. We examine Douglas-fir growth responses to temperature, dewpoint deficit (DPD), soil moisture, and SNC using time series intervention analysis of intra-annual tree-ring width data collected at nine forest stands in western Oregon, USA. The effects of temperature and SNC were similar in importance on tree growth at all sites. Previous-year DPD during the annual drought period was a key factor limiting growth regionally. Winter temperature was more important at high elevation cool sites, whereas summer temperature was more important at warm and dry sites. Growth rate increased with summer temperature to an optimum (Topt) then decreased at higher temperatures. At drier sites, temperature and water affected growth interactively such that Topt decreased with decreasing summer soil moisture. With climate change, growth rates increased at high elevation sites and declined at mid-elevation inland sites since ~1990. Growth response to climate is masked by SNC regionally. We conclude that as temperature rises and precipitation patterns shift towards wetter winters and drier summers, Douglas-fir will experience greater temperature and water stress and an increase in severity of SNC. By the end of the 21st century, climate models predict hotter, drier summers and warmer, wetter winters in the Pac

  15. Stocktype and Vegetative Competition Influences on Pseudotsuga menziesii and Larix occidentalis Seedling Establishment

    Directory of Open Access Journals (Sweden)

    Jeremiah R. Pinto

    2018-04-01

    Full Text Available Douglas fir (Pseudotsuga menziesii var. glauca (Mayr Franco, and western larch (Larix occidentalis Nutt. are species of ecological and commercial importance that occur throughout the Western United States. Effective reforestation of these species relies on successful seedling establishment, which is affected by planting stock quality, stocktype size, and site preparation techniques. This study examined the effects of container volume (80, 130, 200, and 250 cm3 and vegetative competition on seedling survival and physiological and morphological responses for two years, post-outplanting. Glyphosate application (GS and grass planting (HC were used to achieve low and high levels of competition. For all measured attributes, the container volume × vegetative competition was not significant. Mortality was strongly influenced by competition, with higher mortality observed for Douglas fir and western larch planted in HC plots one (28% and 98% and two (61% and 99% years following outplanting. When competition was controlled, seedlings of both species exhibited greater net photosynthesis (>9 μmol m−2 s−1, greater predawn water potential (>−0.35 MPa, and lower mortality (2–3% following one year in the field, indicating establishment success. The 80 cm3 stocktype remained significantly smaller and exhibited lower growth rates for the duration of the study, while all other stocktypes were statistically similar. Our results demonstrate the importance of controlling vegetative competition regardless of stocktype, especially for western larch, and suggest that benefits to post-planting seedling physiology and growth in relation to container size plateau beyond 130 cm3 among the investigated stocktypes.

  16. Tree-ring stable isotopes record the impact of a foliar fungal pathogen on CO(2) assimilation and growth in Douglas-fir.

    Science.gov (United States)

    Saffell, Brandy J; Meinzer, Frederick C; Voelker, Steven L; Shaw, David C; Brooks, J Renée; Lachenbruch, Barbara; McKay, Jennifer

    2014-07-01

    Swiss needle cast (SNC) is a fungal disease of Douglas-fir (Pseudotsuga menziesii) that has recently become prevalent in coastal areas of the Pacific Northwest. We used growth measurements and stable isotopes of carbon and oxygen in tree-rings of Douglas-fir and a non-susceptible reference species (western hemlock, Tsuga heterophylla) to evaluate their use as proxies for variation in past SNC infection, particularly in relation to potential explanatory climate factors. We sampled trees from an Oregon site where a fungicide trial took place from 1996 to 2000, which enabled the comparison of stable isotope values between trees with and without disease. Carbon stable isotope discrimination (Δ(13)C) of treated Douglas-fir tree-rings was greater than that of untreated Douglas-fir tree-rings during the fungicide treatment period. Both annual growth and tree-ring Δ(13)C increased with treatment such that treated Douglas-fir had values similar to co-occurring western hemlock during the treatment period. There was no difference in the tree-ring oxygen stable isotope ratio between treated and untreated Douglas-fir. Tree-ring Δ(13)C of diseased Douglas-fir was negatively correlated with relative humidity during the two previous summers, consistent with increased leaf colonization by SNC under high humidity conditions that leads to greater disease severity in following years. © 2013 John Wiley & Sons Ltd.

  17. Seasonal patterns of bole water content in old growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco)

    Science.gov (United States)

    Large, old conifer trees in the Pacific Northwest (PNW), USA purportedly ameliorate the effects of seasonal summer drought by drawing down the water content of bole tissues over the summer months and refilling during the winter. Continuous monitoring of bole relative water conten...

  18. Virulence of Fusarium oxysporum and F. commune to Douglas-fir (Pseudotsuga menziesii) seedlings

    Science.gov (United States)

    J. E. Stewart; Z. Abdo; R. K. Dumroese; N. B. Klopfenstein; M. -S. Kim

    2012-01-01

    Fusarium species can cause damping-off and root rot of young conifer seedlings, resulting in severe crop and economic losses in forest nurseries. Disease control within tree nurseries is difficult because of the inability to characterize and quantify Fusarium spp. populations with regard to disease potential because of high variability in isolate virulence. Fusarium...

  19. Fusarium oxysporum protects Douglas-fir (Pseudotsuga menziesii) seedlings from root disease caused by Fusarium commune

    Science.gov (United States)

    R. Kasten Dumroese; Mee-Sook Kim; Robert L. James

    2012-01-01

    Fusarium root disease can be a serious problem in forest and conservation nurseries in the western United States. Fusarium inoculum is commonly found in most container and bareroot nurseries on healthy and diseased seedlings, in nursery soils, and on conifer seeds. Fusarium spp. within the F. oxysporum species complex have been recognized as pathogens for more than a...

  20. FIRE RESISTANCE OF DOUGLAS FIR [Pseudotsuga menziesii (Mirb. Franco] WOOD TREATED WITH SOME CHEMICALS

    Directory of Open Access Journals (Sweden)

    M. Kemal YALINKILIÇ

    1998-02-01

    Full Text Available Combustible properties of treated douglas wood specimens and fire-retardancy of some preservatives were tested in this study. Crib test of ASTM E 160-150 was followed. Results indicated that, aqueous solutions of boric acid (BA, borax (Bx (Na2BO7 10H2O or BA + Bx mixture (7: 3, w: w had fire retardant efficacy (FRE over untreated wood and reduced the combustibility of vinil monomers (Styrene and methylmetacrylate which were applied as secondary treatment.

  1. Breeding graft-compatible Douglas-fir rootstocks (Pseudotsuga menziesii (Mirb.) Franco).

    Science.gov (United States)

    D.L. Copes

    1999-01-01

    A study encompassing 24 years was conducted to determine if a breeding program could produce highly graft-compatible rootstocks. Twenty-seven trees of apparent high graft compatibility were selected and crossed to produce 226 control-pollinated families. Seedlings were grown, field planted, and grafted with test scions. Graft unions from field tests were evaluated...

  2. Soil spore bank communities of ectomycorrhizal fungi in endangered Chinese Douglas-fir forests.

    Science.gov (United States)

    Wen, Zhugui; Shi, Liang; Tang, Yangze; Hong, Lizhou; Xue, Jiawang; Xing, Jincheng; Chen, Yahua; Nara, Kazuhide

    2018-01-01

    Chinese Douglas-fir (Pseudotsuga sinensis) is an endangered Pinaceae species found in several isolated regions of China. Although soil spore banks of ectomycorrhizal (ECM) fungi can play an important role in seedling establishment after disturbance, such as in the well-known North American relative (Pseudotsuga menziesii), we have no information about soil spore bank communities in relict forests of Chinese Douglas-fir. We conducted bioassays of 73 soil samples collected from three Chinese Douglas-fir forests, using North American Douglas-fir as bait seedlings, and identified 19 species of ECM fungi. The observed spore bank communities were significantly different from those found in ECM fungi on the roots of resident trees at the same sites (p = 0.02). The levels of potassium (K), nitrogen (N), organic matter, and the pH of soil were the dominant factors shaping spore bank community structure. A new Rhizopogon species was the most dominant species in the spore banks. Specifically, at a site on Sanqing Mountain, 22 of the 57 surviving bioassay seedlings (representing 21 of the 23 soil samples) were colonized by this species. ECM fungal richness significantly affected the growth of bioassay seedlings (R 2  = 0.20, p = 0.007). Growth was significantly improved in seedlings colonized by Rhizopogon or Meliniomyces species compared with uncolonized seedlings. Considering its specificity to Chinese Douglas-fir, predominance in the soil spore banks, and positive effect on host growth, this new Rhizopogon species could play critical roles in seedling establishment and forest regeneration of endangered Chinese Douglas-fir.

  3. A SNP resource for Douglas-fir: de novo transcriptome assembly and SNP detection and validation.

    Science.gov (United States)

    Howe, Glenn T; Yu, Jianbin; Knaus, Brian; Cronn, Richard; Kolpak, Scott; Dolan, Peter; Lorenz, W Walter; Dean, Jeffrey F D

    2013-02-28

    Douglas-fir (Pseudotsuga menziesii), one of the most economically and ecologically important tree species in the world, also has one of the largest tree breeding programs. Although the coastal and interior varieties of Douglas-fir (vars. menziesii and glauca) are native to North America, the coastal variety is also widely planted for timber production in Europe, New Zealand, Australia, and Chile. Our main goal was to develop a SNP resource large enough to facilitate genomic selection in Douglas-fir breeding programs. To accomplish this, we developed a 454-based reference transcriptome for coastal Douglas-fir, annotated and evaluated the quality of the reference, identified putative SNPs, and then validated a sample of those SNPs using the Illumina Infinium genotyping platform. We assembled a reference transcriptome consisting of 25,002 isogroups (unique gene models) and 102,623 singletons from 2.76 million 454 and Sanger cDNA sequences from coastal Douglas-fir. We identified 278,979 unique SNPs by mapping the 454 and Sanger sequences to the reference, and by mapping four datasets of Illumina cDNA sequences from multiple seed sources, genotypes, and tissues. The Illumina datasets represented coastal Douglas-fir (64.00 and 13.41 million reads), interior Douglas-fir (80.45 million reads), and a Yakima population similar to interior Douglas-fir (8.99 million reads). We assayed 8067 SNPs on 260 trees using an Illumina Infinium SNP genotyping array. Of these SNPs, 5847 (72.5%) were called successfully and were polymorphic. Based on our validation efficiency, our SNP database may contain as many as ~200,000 true SNPs, and as many as ~69,000 SNPs that could be genotyped at ~20,000 gene loci using an Infinium II array-more SNPs than are needed to use genomic selection in tree breeding programs. Ultimately, these genomic resources will enhance Douglas-fir breeding and allow us to better understand landscape-scale patterns of genetic variation and potential responses to

  4. The Douglas-Fir Genome Sequence Reveals Specialization of the Photosynthetic Apparatus in Pinaceae

    Directory of Open Access Journals (Sweden)

    David B. Neale

    2017-09-01

    Full Text Available A reference genome sequence for Pseudotsuga menziesii var. menziesii (Mirb. Franco (Coastal Douglas-fir is reported, thus providing a reference sequence for a third genus of the family Pinaceae. The contiguity and quality of the genome assembly far exceeds that of other conifer reference genome sequences (contig N50 = 44,136 bp and scaffold N50 = 340,704 bp. Incremental improvements in sequencing and assembly technologies are in part responsible for the higher quality reference genome, but it may also be due to a slightly lower exact repeat content in Douglas-fir vs. pine and spruce. Comparative genome annotation with angiosperm species reveals gene-family expansion and contraction in Douglas-fir and other conifers which may account for some of the major morphological and physiological differences between the two major plant groups. Notable differences in the size of the NDH-complex gene family and genes underlying the functional basis of shade tolerance/intolerance were observed. This reference genome sequence not only provides an important resource for Douglas-fir breeders and geneticists but also sheds additional light on the evolutionary processes that have led to the divergence of modern angiosperms from the more ancient gymnosperms.

  5. 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...

  6. Thinning shock and response to fertilizer less than expected in young Douglas-fir stand at Wind River Experimental Forest.

    Science.gov (United States)

    Dean S. DeBell; Constance A. Harrington; John. Shumway

    2002-01-01

    Three thinning treatments (thinned to 3.7 by 3.7 m, thinned to 4.3 by 4.3 m, and an unthinned control treatment with nominal spacing averaging 2.6 by 2.6 m) were installed in a 10-year-old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) plantation growing on a low-quality site at the Wind River Experimental Forest in southwest Washington. Two...

  7. Effects of long-term pruning, meristem origin, and branch order on the rooting of Douglas-fir stem cuttings.

    Science.gov (United States)

    D.L. Copes

    1992-01-01

    The rooting percentages of 14 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) clones were examined annually from 1974 to 1988. The trees were 10 and 13 years old in 1974 and were pruned to 2.0 m in 1978 and 1979 and then recut annually to 0.5, 1.0, or 1.5 m, starting in 1983. The pruned trees showed no evidence of decreased rooting percentage...

  8. Transcription through the eye of a needle: daily and annual cyclic gene expression variation in Douglas-fir needles

    OpenAIRE

    Cronn, Richard; Dolan, Peter C.; Jogdeo, Sanjuro; Wegrzyn, Jill L.; Neale, David B.; St. Clair, J. Bradley; Denver, Dee R.

    2017-01-01

    Background Perennial growth in plants is the product of interdependent cycles of daily and annual stimuli that induce cycles of growth and dormancy. In conifers, needles are the key perennial organ that integrates daily and seasonal signals from light, temperature, and water availability. To understand the relationship between seasonal cycles and seasonal gene expression responses in conifers, we examined diurnal and circannual needle mRNA accumulation in Douglas-fir (Pseudotsuga menziesii) n...

  9. Transcription Through The Eye Of A Needle: Daily And Annual Cycles Of Gene Expression Variation In Douglas-Fir Needles

    OpenAIRE

    Dolan, Peter; Cronn, Richard; Denver, Dee; Clair, J.; Neale, David; Wegrzyn, Jill; Jogdeo, Sanjuro

    2017-01-01

    Background: Perennial growth in plants is the product of interdependent cycles of daily and annual stimuli that induce cycles of growth and dormancy. In conifers, needles are the key perennial organ that integrates daily and seasonal signals from light, temperature, and water availability. To understand the relationship between seasonal rhythms and seasonal gene expression responses in conifers, we examined diurnal and circannual needle mRNA accumulation in Douglas-fir (Pseudotsuga menziesii)...

  10. Extinction Risk of Pseudotsuga Menziesii Populations in the Central Region of Mexico: An AHP Analysis

    Directory of Open Access Journals (Sweden)

    Javier López-Upton

    2015-05-01

    Full Text Available Within the Analytic Hierarchy Process (AHP framework, a hierarchical model was created considering anthropogenic, genetic and ecological criteria and sub-criteria that directly affect Douglas-fir (Pseudotsuga menziesii (Mirb. risk of extinction in central Mexico. The sub-criteria values were standardized, weighted, and ordered by importance in a pairwise comparison matrix; the model was mathematically integrated to quantify the degree of extinction risk for each of the 29 populations present in the study area. The results indicate diverse levels of risk for the populations, ranging from very low to very high. Estanzuela, Presa Jaramillo, Peñas Cargadas and Plan del Baile populations have very low risk, with values less than 0.25. On the other hand, Vicente Guerrero, Morán, Minatitlán, La Garita and Tonalapa populations have very high risk (>0.35 because they are heavily influenced by anthropogenic (close to roads and towns, ecological (presence of exotic species and little or no natural regeneration and genetic (presence of mature to overmature trees and geographic isolation factors. In situ conservation activities, prioritizing their implementation in populations at most risk is highly recommended; in addition, germplasm collection for use of assisted gene flow and migration approaches, including artificial reforestation, should be considered in these locations.

  11. Increased water deficit decreases Douglas fir growth throughout western US forests.

    Science.gov (United States)

    Restaino, Christina M; Peterson, David L; Littell, Jeremy

    2016-08-23

    Changes in tree growth rates can affect tree mortality and forest feedbacks to the global carbon cycle. As air temperature increases, evaporative demand also increases, increasing effective drought in forest ecosystems. Using a spatially comprehensive network of Douglas fir (Pseudotsuga menziesii) chronologies from 122 locations that represent distinct climate environments in the western United States, we show that increased temperature decreases growth via vapor pressure deficit (VPD) across all latitudes. Using an ensemble of global circulation models, we project an increase in both the mean VPD associated with the lowest growth extremes and the probability of exceeding these VPD values. As temperature continues to increase in future decades, we can expect deficit-related stress to increase and consequently Douglas fir growth to decrease throughout its US range.

  12. Competitive relations between Douglas-fir and Pacific madrone on shallow soils in a Mediterranean climate

    Science.gov (United States)

    Wang, Zheng Q.; Newton, M.; Tappeiner, J. C.

    1995-01-01

    A large area of Pacific Coast forests is characterized by shallow soil, with negligible rainfall in the growing season. This study explores water-seeking strategy on such a site. We studied availability of bedrock water and its effects on growth and ecophysiology of 11-yr-old planted Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and sprouting Pacific madrone (Arbutus menziesii Pursh). The study was carried out at three regulated densities of madrone sprouts on shallow ( 0.05) among three densities of madrone. However, cover in plots with the highest density of madrone (1322 sprout clumps/ha) depleted 50 mm of water from the 1.5 m layer by June, whereas vegetation on lower density treatments withdrew 15-28 mm by June, with later withdrawal distributed more uniformly through the growing season. Madrone density significantly affected basal diameter (P a?? 0.0001) and height growth (P a?? 0.002) of Douglas-fir. Madrone was consistently taller than Douglas-fir in all plots. The height of 11-yr-old madrone sprout clumps (424-465 cm) did not differ significantly among densities. Madrone leaf area index and biomass were higher at the high density of madrone than at medium density (P a?? 0.045, LAI; P a?? 0.001, biomass). Physiological advantages and rooting habits of madrone give it a competitive advantage over Douglas-fir in this area that it might not have if bedrock did not provide the principal water reservoir for summer growth.

  13. Incorporating genetic variation into a model of budburst phenology of coast Douglas-fir (Pseudotsuga menziesii var

    Science.gov (United States)

    Peter J. Gould; Constance A. Harrington; Bradley J. St Clair

    2011-01-01

    Models to predict budburst and other phenological events in plants are needed to forecast how climate change may impact ecosystems and for the development of mitigation strategies. Differences among genotypes are important to predicting phenological events in species that show strong clinal variation in adaptive traits. We present a model that incorporates the effects...

  14. Growth responses of young Douglas-fir and tanoak 11 years after various levels of hardwood removal and understory suppression in southwestern Oregon, USA

    Science.gov (United States)

    Harrington, T.B.; Tappeiner, John C.

    1997-01-01

    At two sites in southwestern Oregon, height, diameter, and crown width of young Douglas-fir (Pseudotsuga menziesii) and sprout-origin tanoak (Lithocarpus densiflorus) were measured 1–11 years after reducing the density of a 2-year-old tanoak stand to 0%, 25%, 50%, and 100% of its initial cover. Some plots also included suppression of understory vegetation. Tanoak cover developed linearly with time, with steepness of the growth trajectory increasing at a diminishing rate with increasing percentage of initial tanoak cover. Fifth-year cover of understory vegetation declined linearly with increasing percentage of initial tanoak cover (R2 = 0.29). Survival of Douglas-fir (96–100%) differed little among initial abundances of tanoak, while growth trajectories for its size became increasingly exponential with decreasing percentage of initial tanoak cover. Eleventh-year heights of Douglas-fir were similar for 0%, 25%, and 50% of initial tanoak cover; however, diameter increased linearly with decreasing percentage of initial tanoak cover (R2 = 0.73), and the slope of the relationship steepened with understory suppression. Our results indicate that young stands exhibiting a wide range of stand compositions and productivities can be established by early manipulations of tanoak and understory abundance. Complete removal of tanoak plus understory suppression are necessary to maximize Douglas-fir growth, while productive, mixed stands can be achieved by removing 50% or more of tanoak cover.

  15. Tolerance to multiple climate stressors: A case study of Douglas-fir drought and cold hardiness

    Science.gov (United States)

    Bansal, Sheel; Harrington, Constance A; St. Clair, John Bradley

    2016-01-01

    Summary: 1. Drought and freeze events are two of the most common forms of climate extremes which result in tree damage or death, and the frequency and intensity of both stressors may increase with climate change. Few studies have examined natural covariation in stress tolerance traits to cope with multiple stressors among wild plant populations. 2. We assessed the capacity of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii), an ecologically and economically important species in the northwestern USA, to tolerate both drought and cold stress on 35 populations grown in common gardens. We used principal components analysis to combine drought and cold hardiness trait data into generalized stress hardiness traits to model geographic variation in hardiness as a function of climate across the Douglas-fir range. 3. Drought and cold hardiness converged among populations along winter temperature gradients and diverged along summer precipitation gradients. Populations originating in regions with cold winters had relatively high tolerance to both drought and cold stress, which is likely due to overlapping adaptations for coping with winter desiccation. Populations from regions with dry summers had increased drought hardiness but reduced cold hardiness, suggesting a trade-off in tolerance mechanisms. 4. Our findings highlight the necessity to look beyond bivariate trait–climate relationships and instead consider multiple traits and climate variables to effectively model and manage for the impacts of climate change on widespread species.

  16. MORFOGÉNESIS IN VITRO DE Pseudotsuga menziesii VAR. glauca

    Directory of Open Access Journals (Sweden)

    María Guadalupe Carrillo-Benítez

    2011-01-01

    Full Text Available Se evaluó la respuesta morfogénica a partir de embriones cigóticos cultivados in vitro de semilla almacenada (un año de Pseudotsuga menziesii var. glauca recolectada en Tlaxcala. Las semillas fueron desinfestadas con detergente y H2O2 (3 % v/v durante 48 h en agitación a 50 rpm, cultivadas en el medio de Murashige y Skoog (1962 sin reguladores. La germinación ocurrió después de siete días y posteriormente subcultivados a un medio MS con 2,4-D (3 mg·L-1 y BA (1 mg·L-1. Con los callos obtenidos en un medio HS se evaluaron tres concentraciones de ABA para promover formación de estructuras embrionarias, presentándose el mejor tratamiento con concentración de 10.0 mg·L-1 (P<.0001. El mejor desarrollo de plántulas se presentó empleando un medio Murashige y Skoog (1962 con sacarosa al 6 %. Se usaron micorrizas para mejor adaptación de plántulas a suelo. No hubo formación de raíces.

  17. Douglas-Fir Tussock Moth

    Science.gov (United States)

    Boyd E. Wickman; Richard R. Mason; Galen C. Trostle

    1981-01-01

    The Douglas-fir tussock moth (Orgyia pseudotsugata McDunnough) is an important defoliator of true firs and Douglas-fir in Western North America. Severe tussock moth outbreaks have occurred in British Columbia, Idaho, Washington, Oregon, Nevada, California, Arizona, and New Mexico, but the area subject to attack is more extensive

  18. Foliar nitrogen metabolism of adult Douglas-fir trees is affected by soil water availability and varies little among provenances.

    Science.gov (United States)

    Du, Baoguo; Kreuzwieser, Jürgen; Dannenmann, Michael; Junker, Laura Verena; Kleiber, Anita; Hess, Moritz; Jansen, Kirstin; Eiblmeier, Monika; Gessler, Arthur; Kohnle, Ulrich; Ensminger, Ingo; Rennenberg, Heinz; Wildhagen, Henning

    2018-01-01

    The coniferous forest tree Douglas-fir (Pseudotsuga menziesii) is native to the pacific North America, and is increasingly planted in temperate regions worldwide. Nitrogen (N) metabolism is of great importance for growth, resistance and resilience of trees. In the present study, foliar N metabolism of adult trees of three coastal and one interior provenance of Douglas-fir grown at two common gardens in southwestern Germany (Wiesloch, W; Schluchsee, S) were characterized in two subsequent years. Both the native North American habitats of the seed sources and the common garden sites in Germany differ in climate conditions. Total and mineral soil N as well as soil water content were higher in S compared to W. We hypothesized that i) provenances differ constitutively in N pool sizes and composition, ii) N pools are affected by environmental conditions, and iii) that effects of environmental factors on N pools differ among interior and coastal provenances. Soil water content strongly affected the concentrations of total N, soluble protein, total amino acids (TAA), arginine and glutamate. Foliar concentrations of total N, soluble protein, structural N and TAA of trees grown at W were much higher than in trees at S. Provenance effects were small but significant for total N and soluble protein content (interior provenance showed lowest concentrations), as well as arginine, asparagine and glutamate. Our data suggest that needle N status of adult Douglas-fir is independent from soil N availability and that low soil water availability induces a re-allocation of N from structural N to metabolic N pools. Small provenance effects on N pools suggest that local adaptation of Douglas-fir is not dominated by N conditions at the native habitats.

  19. Variation in water potential, hydraulic characteristics and water source use in montane Douglas-fir and lodgepole pine trees in southwestern Alberta and consequences for seasonal changes in photosynthetic capacity.

    Science.gov (United States)

    Andrews, Shilo F; Flanagan, Lawrence B; Sharp, Eric J; Cai, Tiebo

    2012-02-01

    Tree species response to climate change-induced shifts in the hydrological cycle depends on many physiological traits, particularly variation in water relations characteristics. We evaluated differences in shoot water potential, vulnerability of branches to reductions in hydraulic conductivity, and water source use between Pinus contorta Dougl. ex Loud. var. latifolia Engelm. (lodgepole pine) and Pseudotsuga menziesii (Mirb.) Franco (interior Douglas-fir), and determined the consequences for seasonal changes in photosynthetic capacity. The Douglas-fir site had soil with greater depth, finer texture and higher organic matter content than soil at the lodgepole pine site, all factors that increased the storage of soil moisture. While the measured xylem vulnerability curves were quite similar for the two species, Douglas-fir had lower average midday shoot water potentials than did lodgepole pine. This implied that lodgepole pine exhibited stronger stomatal control of transpiration than Douglas-fir, which helped to reduce the magnitude of the water potential gradient required to access water from drying soil. Stable hydrogen isotope measurements indicated that Douglas-fir increased the use of groundwater during mid-summer when precipitation inputs were low, while lodgepole pine did not. There was a greater reduction of photosynthetic carbon gain in lodgepole pine compared with Douglas-fir when the two tree species were exposed to seasonal declines in soil water content. The contrasting patterns of seasonal variation in photosynthetic capacity observed for the two species were a combined result of differences in soil characteristics at the separate sites and the inherent physiological differences between the species.

  20. Multilocus patterns of nucleotide diversity and divergence reveal positive selection at candidate genes related to cold hardiness in coastal Douglas Fir (Pseudotsuga menziesii var. menziesii).

    Science.gov (United States)

    A. Eckert; J. Wegrzyn; B. Pande; K. Jermstad; J. Lee; J. Liechty; B. Tearse; K. Krutovsky; D. Neale

    2009-01-01

    Forest trees exhibit remarkable adaptations to their environments. The genetic basis for phenotypic adaptation to climatic gradients has been established through a long history of common garden, provenance, and genecological studies. The identities of genes underlying these traits, however, have remained elusive and thus so have the patterns of adaptive molecular...

  1. Drought effects on root and needle terpenoid content of a coastal and an interior Douglas fir provenance.

    Science.gov (United States)

    Kleiber, Anita; Duan, Qiuxiao; Jansen, Kirstin; Verena Junker, Laura; Kammerer, Bernd; Rennenberg, Heinz; Ensminger, Ingo; Gessler, Arthur; Kreuzwieser, Jürgen

    2017-12-01

    Douglas fir (Pseudotsuga menziesii) is a conifer species that stores large amounts of terpenoids, mainly monoterpenoids in resin ducts of various tissues. The effects of drought on stored leaf terpenoid concentrations in trees are scarcely studied and published data are partially controversial, since reduced, unaffected or elevated terpenoid contents due to drought have been reported. Even less is known on the effect of drought on root terpenoids. In the present work, we investigated the effect of reduced water availability on the terpenoid content in roots and needles of Douglas fir seedlings. Two contrasting Douglas fir provenances were studied: an interior provenance (var. glauca) with assumed higher drought resistance, and a coastal provenance (var. menziesii) with assumed lower drought resistance. We tested the hypothesis that both provenances show specific patterns of stored terpenoids and that the patterns will change in response to drought in both, needles and roots. We further expected stronger changes in the less drought tolerant coastal provenance. For this purpose, we performed an experiment under controlled conditions, in which the trees were exposed to moderate and severe drought stress. According to our expectations, the study revealed clear provenance-specific terpenoid patterns in needles. However, such patterns were not detected in the roots. Drought slightly increased the needle terpenoid contents of the coastal but not of the interior provenance. We also observed increased terpenoid abundance mainly in roots of the moderately stressed coastal provenance. Overall, from the observed provenance-specific reactions with increased terpenoid levels in trees of the coastal origin in response to drought, we conclude on functions of terpenoids for abiotic stress tolerance that might be fulfilled by other, constitutively expressed mechanisms in drought-adapted interior provenances. © The Author 2017. Published by Oxford University Press. All rights

  2. Comparative genetic responses to climate in the varieties of Pinus ponderosa and Pseudotsuga menziesii: reforestation

    Science.gov (United States)

    Gerald E. Rehfeldt; Barry C. Jaquish; Cuauhtemoc Saenz-Romero; Dennis G. Joyce; Laura P. Leites; J. Bradley St Clair; Javier Lopez-Upton

    2014-01-01

    Impacts of climate change on the climatic niche of the sub-specific varieties of Pinus ponderosa and Pseudotsuga menziesii and on the adaptedness of their populations are considered from the viewpoint of reforestation. In using climate projections from an ensemble of 17 general circulation models targeting the decade surrounding 2060, our analyses suggest that a...

  3. Comparison of leaf gas exchange and stable isotope signature of water-soluble compounds along canopy gradients of co-occurring Douglas-fir and European beech.

    Science.gov (United States)

    Bögelein, Rebekka; Hassdenteufel, Martin; Thomas, Frank M; Werner, Willy

    2012-07-01

    Combined δ(13) C and δ(18) O analyses of water-soluble leaf and twig phloem material were used to determine intrinsic water-use efficiency (iWUE) and variability of stomatal conductance at different crown positions in adult European beech (Fagus sylvatica) and Douglas-fir (Pseudotsuga menziesii) trees. Simultaneous gas exchange measurements allowed evaluation of the differences in calculating iWUE from leaf or phloem water-soluble compounds, and comparison with a semi-quantitative dual isotope model to infer variability of net photosynthesis (A(n) ) between the investigated crown positions. Estimates of iWUE from δ(13) C of leaf water-soluble organic matter (WSOM) outperformed the estimates from phloem compounds. In the beech crown, δ(13) C of leaf WSOM coincided clearly with gas exchange measurements. The relationship was not as reliable in the Douglas-fir. The differences in δ(18) O between leaf and phloem material were found to correlate with stomatal conductance. The semi-quantitative model approach was applicable for comparisons of daily average A(n) between different crown positions and trees. Intracanopy gradients were more pronounced in the beech than in the Douglas-fir, which reached higher values of iWUE at the respective positions, particularly under dry air conditions. © 2012 Blackwell Publishing Ltd.

  4. Growth phenology of coast Douglas-fir seed sources planted in diverse environments

    Science.gov (United States)

    Peter J. Gould; Constance A. Harrington; J. Bradley St. Clair

    2012-01-01

    The timing of periodic life cycle events in plants (phenology) is an important factor determining how species and populations will react to climate change. We evaluated annual patterns of basal-area and height growth of coast Douglas-fir (Pseudotusuga menziesii var. menziesii (Mirb.) Franco) seedlings from four seed sources...

  5. Species distribution models may misdirect assisted migration: insights from the introduction of Douglas-fir to Europe.

    Science.gov (United States)

    Boiffin, Juliette; Badeau, Vincent; Bréda, Nathalie

    2017-03-01

    Species distribution models (SDMs), which statistically relate species occurrence to climatic variables, are widely used to identify areas suitable for species growth under future climates and to plan for assisted migration. When SDMs are projected across times or spaces, it is assumed that species climatic requirements remain constant. However, empirical evidence supporting this assumption is rare, and SDM predictions could be biased. Historical human-aided movements of tree species can shed light on the reliability of SDM predictions in planning for assisted migration. We used Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), a North American conifer introduced into Europe during the mid-19th century, as a case-study to test niche conservatism. We combined transcontinental data sets of Douglas-fir occurrence and climatic predictors to compare the realized niches between native and introduced ranges. We calibrated a SDM in the native range and compared areas predicted to be climatically suitable with observed presences. The realized niches in the native and introduced ranges showed very limited overlap. The SDM calibrated in North America had very high predictive power in the native range, but failed to predict climatic suitability in Europe where Douglas-fir grows in climates that have no analogue in the native range. We review the ecological mechanisms and silvicultural practices that can trigger such shifts in realized niches. Retrospective analysis of tree species introduction revealed that the assumption of niche conservatism is erroneous. As a result, distributions predicted by SDM are importantly biased. There is a high risk that assisted migration programs may be misdirected and target inadequate species or introduction zones. © 2016 by the Ecological Society of America.

  6. Local adaptation in migrated interior Douglas-fir seedlings is mediated by ectomycorrhizas and other soil factors.

    Science.gov (United States)

    Pickles, Brian J; Twieg, Brendan D; O'Neill, Gregory A; Mohn, William W; Simard, Suzanne W

    2015-08-01

    Separating edaphic impacts on tree distributions from those of climate and geography is notoriously difficult. Aboveground and belowground factors play important roles, and determining their relative contribution to tree success will greatly assist in refining predictive models and forestry strategies in a changing climate. In a common glasshouse, seedlings of interior Douglas-fir (Pseudotsuga menziesii var. glauca) from multiple populations were grown in multiple forest soils. Fungicide was applied to half of the seedlings to separate soil fungal and nonfungal impacts on seedling performance. Soils of varying geographic and climatic distance from seed origin were compared, using a transfer function approach. Seedling height and biomass were optimized following seed transfer into drier soils, whereas survival was optimized when elevation transfer was minimised. Fungicide application reduced ectomycorrhizal root colonization by c. 50%, with treated seedlings exhibiting greater survival but reduced biomass. Local adaptation of Douglas-fir populations to soils was mediated by soil fungi to some extent in 56% of soil origin by response variable combinations. Mediation by edaphic factors in general occurred in 81% of combinations. Soil biota, hitherto unaccounted for in climate models, interacts with biogeography to influence plant ranges in a changing climate. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  7. Fertilizing Douglas-fir forests.

    Science.gov (United States)

    Richard E. Miller; Roger D. Right

    1979-01-01

    This report supplements a slide-tape presentation of the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir forests in western Washington and Oregon and the effects of this fertilization on tree growth and water quality. Part II discusses factors that affect costs and revenues from investments in forest...

  8. Comparative genetic responses to climate in the varieties of Pinus ponderosa and Pseudotsuga menziesii: clines in growth potential

    Science.gov (United States)

    Gerald E. Rehfeldt; Laura P. Leites; J. Bradley St Clair; Barry C. Jaquish; Cuauhtemoc Saenz-Romero; Javier Lopez-Upton; Dennis G. Joyce

    2014-01-01

    Height growth data were assembled from 10 Pinus ponderosa and 17 Pseudotsuga menziesii provenance tests. Data from the disparate studies were scaled according to climate similarities of the provenances to provide single datasets for 781 P. ponderosa and 1193 P. menziesii populations. Mixed effects models were used for two sub-specific varieties of each species to...

  9. Simulation of carbon and water budgets of a Douglas-fir forest

    NARCIS (Netherlands)

    Wijk, van M.T.; Dekker, S.C.; Bouten, W.; Kohsiek, W.; Mohren, G.M.J.

    2001-01-01

    The forest growth/hydrology model FORGRO–SWIF, consisting of a forest growth and a soil water model, was applied to quantify the inter-annual variability of the carbon and water budgets of a Douglas-fir forest (Pseudotsuga menziessii (Mirb.) Franco) in The Netherlands. With these budgets, the water

  10. Transcriptome Changes in Douglas-fir (Pseudotsuga menziesii) Induced by Exposure to Diesel Emissions Generated with CeO2 Nanoparticle Fuel Additive

    Science.gov (United States)

    When cerium oxide nanoparticles are added to diesel fuel, fuel burning efficiency increases, producing emissions (DECe) with characteristics that differ from conventional diesel exhaust (DE). It has previously been shown that DECe induces more adverse pulmonary effects in rats on...

  11. Effect of environmental and cultural conditions on medium pH and explant growth performance of Douglas-fir ( Pseudotsuga menziesii) shoot cultures

    OpenAIRE

    Chen, Chien-Chih; Bates, Rick; Carlson, John

    2015-01-01

    The medium pH level of plant tissue cultures has been shown to be essential to many aspects of explant development and growth. Sensitivity or tolerance of medium pH change in vitro varies according to specific requirements of individual species. The objectives of this study are to 1) determine medium pH change over time in storage conditions and with presence of explants, 2) evaluate the effects of medium pH change on explant growth performance and 3) assess the effects of adding a pH stabili...

  12. Comparison between mycocenosis living in forest of Cestnut reforested with Douglas Fir; Confronto tra micocenosi presenti nei boschi di latifoglie e rimboschimenti di Douglasia

    Energy Technology Data Exchange (ETDEWEB)

    Andreotti, A.; Serra, F. [ENEA, Centro Ricerche Brasimone, Bologna (Italy). Dipt. Ambiente; Dalla Valle, E.; Govi, G. [Bologna, Univ. (Italy). Dipt. di Protezione e Valorizzazione Agroalimentare. Centro di Micologia

    1997-05-01

    In this technical report the results of a first mycological research carried out from 1989 to 1990 in Brasimone in the high Bolognan Appennines (Northern Italy) are shown. The study was taken up by making a comparison between the fungus community living in forest plots with different vegetation; in particular, the mycocenosis of plots reforested with Douglas Fir (Pseudotsuga (Mirb.) Franco) with those of Beech (Fagus sylvatica L.) and Cestnut (Castanea sativa Mill.) woods were compared. The results show that the specific richness clearly decreases form mixed broad-leaved forest (90 species) to the mono specific plantation of P. menziesii (41 species). Particularly in the artificial plantation with exotic trees, there are few symbiont species while the saprophytic wood and litter fungi abound in relationship with the large bulk of undecomposed vegetable material present in these habitats.

  13. Arthropod prey of Wilson's Warblers in the understory of Douglas-fir forests

    Science.gov (United States)

    Hagar, J.C.; Dugger, K.M.; Starkey, E.E.

    2007-01-01

    Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wilson's Warblers (Wilsonia pusilla) that foraged in the understory of Douglas-fir (Pseudotsuga menziesii) forests in western Oregon during the breeding season. We sampled arthropods at the same sites where diet data were collected, and compared abundance and biomass of prey among seven common shrub species. Wilson's Warblers ate more caterpillars (Lepidoptera larvae), flies (Diptera), beetles (Coleoptera), and Homoptera than expected based on availability. Deciduous shrubs supported higher abundances of arthropod taxa and size classes used as prey by Wilson's Warblers than did evergreen shrubs. The development and maintenance of deciduous understory vegetation in conifer forests of the Pacific Northwest may be fundamental for conservation of food webs that support breeding Wilson's Warblers and other shrub-associated, insectivorous songbirds.

  14. Comparative genetic responses to climate for the varieties of Pinus ponderosa and Pseudotsuga menziesii: realized climate niches

    Science.gov (United States)

    Gerald E. Rehfeldt; Barry C. Jaquish; Javier Lopez-Upton; Cuauhtemoc Saenz-Romero; J. Bradley St Clair; Laura P. Leites; Dennis G. Joyce

    2014-01-01

    The Random Forests classification algorithm was used to predict the occurrence of the realized climate niche for two sub-specific varieties of Pinus ponderosa and three varieties of Pseudotsuga menziesii from presence-absence data in forest inventory ground plots. Analyses were based on ca. 271,000 observations for P. ponderosa and ca. 426,000 observations for P....

  15. Ethanol synthesis and aerobic respiration in the laboratory by leader segments of Douglas-fir seedlings from winter and spring.

    Science.gov (United States)

    Joseph, Gladwin; Kelsey, Rick G

    2004-05-01

    Stem segments from terminal leaders of Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco, seedlings were sampled in mid-December when cambial cells were dormant. The residual, debudded leaders were resampled again in early May when the cambium was metabolically active. May stems had higher constitutive ethanol concentrations than December stems. This was not the result of cambial hypoxia generated by rapid spring respiration rates, because when aerobic respiration was stimulated by incubating the stems in air at 30 degrees C ethanol production was induced in December, but not in May. Rapid respiration rates at 30 degrees C may have depleted O(2) supplies and induced ethanol production in December stems because dormant, thick-walled cambial cells may be less permeable to CO(2) and O(2), compared with metabolically active, thin-walled cambial cells in May. December stem segments incubated in a N(2) atmosphere at 30 degrees C synthesized 1.8 times more ethanol than segments from May, most likely because spring growth had reduced the soluble sugars available for fermentation. CO(2) efflux from May stems (after 5.5 h of incubation at 30 degrees C) was equal to December stems per unit volume, but greater than December stems per unit surface area. N(2)-induced ethanol concentrations were positively related with CO(2) efflux per unit volume, indicating that rapidly respiring leaders can maintain rapid fermentation rates, provided soluble sugars are readily available. N(2)-induced ethanol and CO(2) efflux per unit volume declined with increasing leader diameter in both seasons, whereas there were no relationships between CO(2) efflux per unit surface area and diameter. Cambium physiology and phenology influence the induction of fermentation and concentrations of ethanol produced in terminal leaders of Douglas-fir, and probably other conifers as well. This needs to be considered when comparing fermentation among species, or comparing individuals from different seasons, or

  16. Less than 50% nitrogen retention 1-year after high N additions to Pacific Northwest Douglas-fir forests

    Science.gov (United States)

    Michelsen-Correa, S.; Harrison, R. B.

    2017-12-01

    In Pacific Northwest forests, N is known to be a limiting nutrient particularly in Douglas-fir (Pseudotsuga menziesii) ecosystems. Fertilizers are commonly applied to increase productivity in commercially managed forests. Despite known N limitations, Douglas-fir uptake of applied fertilizers is typically low and highly variable depending on environmental site conditions of a particular forest. We measured N recovery within a 1-year time frame at five sites using a fertilizer enriched in 15N as a tracer. Comparisons were also made between Enhanced Efficiency Fertilizers (EEFs) and an unformulated urea fertilizer to determine if N recovery is improved with fertilizers designed to limit volatile losses of ammonia. Retention was low across all sites and fertilizer types with a mean of 39.0% recovered after 1-year. The largest fertilizer pool was the top 20cm of mineral soil. The use of EFFs as a management tool to improve N use efficiency at the five sites in our study is not supported by our results as no significant differences in total 1-year N recovery or tree uptake of N were observed between treatments. The low N recovery after 1-year but simultaneous increases in above ground biomass support a model of N loss where the ecosystem can continue to accumulate biomass with simultaneous leaching and gaseous losses of N. This conclusion contrasts with the commonly held assumption that fertilization of N limited Douglas-fir forests, should yield negligible losses of N and high recovery of the applied fertilizer. Additionally, we conclude that management decisions regarding fertilizer use efficiency and the benefits of fertilization need to be site specific due to the variable N recovery rates based on site factors as opposed to fertilizer treatment type. Finally, despite differences in the size of available soil N pools the amount of N recovered in the above group pools (i.e. bole wood and foliage) were not significantly different between sites. N uptake by the plants

  17. Transcription through the eye of a needle: daily and annual cyclic gene expression variation in Douglas-fir needles.

    Science.gov (United States)

    Cronn, Richard; Dolan, Peter C; Jogdeo, Sanjuro; Wegrzyn, Jill L; Neale, David B; St Clair, J Bradley; Denver, Dee R

    2017-07-24

    Perennial growth in plants is the product of interdependent cycles of daily and annual stimuli that induce cycles of growth and dormancy. In conifers, needles are the key perennial organ that integrates daily and seasonal signals from light, temperature, and water availability. To understand the relationship between seasonal cycles and seasonal gene expression responses in conifers, we examined diurnal and circannual needle mRNA accumulation in Douglas-fir (Pseudotsuga menziesii) needles at diurnal and circannual scales. Using mRNA sequencing, we sampled 6.1 × 10 9 reads from 19 trees and constructed a de novo pan-transcriptome reference that includes 173,882 tree-derived transcripts. Using this reference, we mapped RNA-Seq reads from 179 samples that capture daily and annual variation. We identified 12,042 diurnally-cyclic transcripts, 9299 of which showed homology to annotated genes from other plant genomes, including angiosperm core clock genes. Annual analysis revealed 21,225 circannual transcripts, 17,335 of which showed homology to annotated genes from other plant genomes. The timing of maximum gene expression is associated with light intensity at diurnal scales and photoperiod at annual scales, with approximately half of transcripts reaching maximum expression +/- 2 h from sunrise and sunset, and +/- 20 days from winter and summer solstices. Comparisons with published studies from other conifers shows congruent behavior in clock genes with Japanese cedar (Cryptomeria), and a significant preservation of gene expression patterns for 2278 putative orthologs from Douglas-fir during the summer growing season, and 760 putative orthologs from spruce (Picea) during the transition from fall to winter. Our study highlight the extensive diurnal and circannual transcriptome variability demonstrated in conifer needles. At these temporal scales, 29% of expressed transcripts show a significant diurnal cycle, and 58.7% show a significant circannual cycle. Remarkably

  18. Douglas-fir growth and yield: research 1909-1960.

    Science.gov (United States)

    R.O. Curtis; D.D. Marshall

    2004-01-01

    Systematic research on growth and yield of Douglas-fir began in 1909. This line of early research evolved over time and culminated in publication of USDA Bulletin 201, The Yield of Douglas-fir in the Pacific Northwest. B201 had an enormous influence on development of Douglas-fir forestry and was arguably the most influential single research publication ever produced in...

  19. Vine maple (Acer circinatum) clone growth and reproduction in managed and unmanaged coastal Oregon douglas-fir forests

    Science.gov (United States)

    O'Dea, Mary E.; Zasada, John C.; Tappeiner, John C.

    1995-01-01

    Vine maple (Acer circinatum Pursh.) clone development, expansion, and regeneration by seedling establishment were studied in 5-240 yr old managed and unmanaged Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in coastal Oregon. Stem length, number of stems, and crown area were all significantly (P @10 m long and basal sprouts 1-2 m long; some stems had been pinned to the forest floor by fallen trees or branches and had layered. In stands >120 yr in age, clones were often quite complex, composed of several decumbent stems each of which connected the ramets of 1-10 new aerial stems. Vine maple clone expansion occurs by the layering of long aerial stems. Over 95% of the layered stems we observed had been pinned to the forest floor by fallen debris. Unsevered stems that we artificially pinned to the forest floor initiated roots within 1 yr. Thinning may favor clonal expansion because fallen slash from thinning often causes entire clones to layer, not just individual stems. Clonal vine maple seed production and seedling establishment occurred in all stages of stand development except dense, young stands following crown closure. There were more seedlings in thinned stands than in unthinned stands and in unburned clearcuts than in burned clearcuts.

  20. 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.

  1. Diet of Wilson's warblers and distribution of arthropod prey in the understory of Douglas-fir forests

    Science.gov (United States)

    Hagar, Joan C.; Dugger, Kate; Starkey, Edward E.

    2007-01-01

    Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wilson's Warblers (Wilsonia pusilla) that foraged in the understory of Douglas-fir (Pseudotsuga menziesii) forests in western Oregon during the breeding season. We sampled arthropods at the same sites where diet data were collected, and compared abundance and biomass of prey among seven common shrub species. Wilson's Warblers ate more caterpillars (Lepidoptera larvae), flies (Diptera), beetles (Coleoptera), and Homoptera than expected based on availability. Deciduous shrubs supported higher abundances of arthropod taxa and size classes used as prey by Wilson's Warblers than did evergreen shrubs. The development and maintenance of deciduous understory vegetation in conifer forests of the Pacific Northwest may be fundamental for conservation of food webs that support breeding Wilson's Warblers and other shrub-associated, insectivorous songbirds.

  2. Inheritance of graft compatibility in Douglas fir.

    Science.gov (United States)

    D.L. Copes

    1973-01-01

    Graft compatibility of genetically related and unrelated rootstock-scion combinations was compared. Scion clones were 75% compatible when grafted on half-related rootstocks but only 56% compatible when grafted on unrelated rootstocks. Most variance associated with graft incompatibility in Douglas-fir appears to be caused by multiple genes.

  3. Architectural analysis of Douglas-fir forests

    NARCIS (Netherlands)

    Kuiper, L.C.

    1994-01-01

    The architecture of natural and semi-natural Douglas-fir forest ecosystems in western Washington and western Oregon was analyzed by various case-studies, to yield vital information needed for the design of new silvicultural systems with a high level of biodiversity, intended for low-input

  4. High gellan gum concentration and secondary somatic embryogenesis: two key factors to improve somatic embryo development in Pseudotsuga menziesii [Mirb.

    Czech Academy of Sciences Publication Activity Database

    Lelu-Walter, M.A.; Gautier, J.; Eliášová, Kateřina; Sanchez, L.; Teyssier, C.; Lomenech, A. M.; Le Metté, C.; Hargreaves, R.; Trontin, J.F.; Reeves, G.

    2018-01-01

    Roč. 132, č. 1 (2018), s. 137-155 ISSN 0167-6857 Institutional support: RVO:61389030 Keywords : Cell density * Cleavage polyembryony * Douglas-fir * Embryogenic potential * Protein pattern * Vegetative propagation Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 2.002, year: 2016

  5. SEASONAL PATTERNS OF PHOTOSYNTHESIS IN DOUGLAS FIR SEEDLINGS DURING THE THIRD AND FOURTH YEAR OF EXPOSURE TO ELEVATED CO2 AND TEMPERATURE

    Science.gov (United States)

    We examined the interactive effects of elevated atmospheric CO2 and temperature on seasonal patterns of photosynthesis in Douglas-fir (Psuedotsuga menziesii (Mirb.) Franco) seedlings. Seedlings were grown in sunlit chambers controlled to track either ambient (~400 ppm) CO2 or am...

  6. Development over 25 years of Douglas-fir, western hemlock, and western redcedar planted at various spacings on a very good site in British Columbia.

    Science.gov (United States)

    Donald L. Reukema; J. Harry G. Smith

    1987-01-01

    Results of five spacing trials on the University of British Columbia Research Forest, covering a range of plantation spacings from 1 to 5 meters, showed that choice of initial spacing is among the most important factors influencing bole and crown development and stand growth and yield. The trials include Douglas-fir (Pseudotsuga menziesi), western...

  7. Douglas-fir tussock moth: an annotated bibliography.

    Science.gov (United States)

    Robert W. Campbell; Lorna C. Youngs

    1978-01-01

    This annotated bibliography includes references to 338 papers. Each deals in some way with either the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), or a related species. Specifically, 210 publications and 82 unpublished documents make some reference, at least, to the Douglas-fir tussock moth; 55 are concerned with other species in...

  8. Elevated Annual Runoff Ratios in Pacific Northwest Catchments Impacted by Epidemic Foliage Disease of Douglas-fir

    Science.gov (United States)

    Bladon, K. D.; Bywater-Reyes, S.; LeBoldus, J. M.; Segura, C.; Ritokova, G.; Shaw, D. C.

    2017-12-01

    Catchments in the Western United States are undergoing unprecedented levels of tree die-off and/or reduced vigor due to increased severity of wildfire, drought, insect outbreaks, and disease. In the U.S. Pacific Northwest, Swiss needle cast (SNC) is the most damaging foliar disease of Douglas-fir (Pseudotsuga menziesii), physically obstructing stomata and preventing CO2 uptake and transpiration. A recent analysis in coastal Oregon indicated a substantial increase in area affected by the disease, from 530.5 km2 in 1996 to 2,387.1 km2 in 2015. Deforestation or reduced tree vigor can have profound impacts on catchment hydrology, in theory, producing increased streamflow due to reduced interception and transpiration. However, these increases have not always been detectable as impacts also depend on factors such as climate and vegetation composition. Moreover, press disturbances, such as insect outbreaks or disease, often do not result in complete removal of understorey or canopy vegetation. We analyzed trends in annual runoff ratios (quotient of discharge divided by precipitation) from 1990-2015 in 12 catchments (183-1,744 km2) in western Oregon. In general, runoff ratios increased by 10-27% in catchments with a total area of SNC >10%, with the most substantial runoff increases in catchments with SNC impacting >25% of the area. Interestingly, the most severely impacted catchment ( 90.5% SNC) showed a decrease in runoff. This is consistent with a potential compensatory response from understory western hemlock (Tsuga heterophylla) trees, a phenomenon observed in the most severely impacted sites. Findings from this study are important for assessing the impacts of biotic forest disturbances on water supply and aquatic ecosystem health.

  9. Slow and fast pyrolysis of Douglas-fir lignin: Importance of liquid-intermediate formation on the distribution of products

    International Nuclear Information System (INIS)

    Zhou, Shuai; Pecha, Brennan; Kuppevelt, Michiel van; McDonald, Armando G.; Garcia-Perez, Manuel

    2014-01-01

    The formation of liquid intermediates and the distribution of products were studied under slow and fast pyrolysis conditions. Results indicate that monomers are formed from lignin oligomeric products during secondary reactions, rather than directly from the native lignin. Lignin from Douglas-fir (Pseudotsuga menziesii) wood was extracted using the milled wood enzyme lignin isolation method. Slow pyrolysis using a microscope with hot-stage captured the liquid formation (>150 °C), shrinking, swelling (foaming), and evaporation behavior of lignin intermediates. The activation energy (E a ) for 5–80% conversions was 213 kJ mol −1 , and the pre-exponential factor (log A) was 24.34. Fast pyrolysis tests in a wire mesh reactor were conducted (300–650 °C). The formation of the liquid intermediate was visualized with a fast speed camera (250 Hz), showing the existence of three well defined steps: formation of lignin liquid intermediates, foaming and liquid intermediate swelling, and evaporation and droplet shrinking. GC/MS and UV-Fluorescence of the mesh reactor condensate revealed lignin oligomer formation but no mono-phenols were seen. An increase in pyrolytic lignin yield was observed as temperature increased. The molar mass determined by ESI-MS was not affected by pyrolysis temperature. SEM of the char showed a smooth surface with holes, evidence of a liquid intermediate with foaming; bursting from these foams could be responsible for the removal of lignin oligomers. Py-GC/MS studies showed the highest yield of guaiacol compounds at 450–550 °C. - Highlights: • The formation of a liquid intermediate phase is a critical step during lignin pyrolysis. • The lignin oligomers are thermally ejected from the liquid intermediate phase. • The mono-phenols are formed mainly from the secondary reactions of lignin oligomers

  10. Tree water storage and its diurnal dynamics related to sap flow and changes in stem volume in old-growth Douglas-fir trees.

    Science.gov (United States)

    Cermák, Jan; Kucera, Jiri; Bauerle, William L; Phillips, Nathan; Hinckley, Thomas M

    2007-02-01

    Diurnal and seasonal tree water storage was studied in three large Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) trees at the Wind River Canopy Crane Research site. Changes in water storage were based on measurements of sap flow and changes in stem volume and tissue water content at different heights in the stem and branches. We measured sap flow by two variants of the heat balance method (with internal heating in stems and external heating in branches), stem volume with electronic dendrometers, and tissue water content gravimetrically. Water storage was calculated from the differences in diurnal courses of sap flow at different heights and their integration. Old-growth Douglas-fir trees contained large amounts of free water: stem sapwood was the most important storage site, followed by stem phloem, branch sapwood, branch phloem and needles. There were significant time shifts (minutes to hours) between sap flow measured at different positions within the transport system (i.e., stem base to shoot tip), suggesting a highly elastic transport system. On selected fine days between late July and early October, when daily transpiration ranged from 150 to 300 liters, the quantity of stored water used daily ranged from 25 to 55 liters, i.e., about 20% of daily total sap flow. The greatest amount of this stored water came from the lower stem; however, proportionally more water was removed from the upper parts of the tree relative to their water storage capacity. In addition to lags in sap flow from one point in the hydrolic pathway to another, the withdrawal and replacement of stored water was reflected in changes in stem volume. When point-to-point lags in sap flow (minutes to hours near the top and stem base, respectively) were considered, there was a strong linear relationship between stem volume changes and transpiration. Volume changes of the whole tree were small (equivalent to 14% of the total daily use of stored water) indicating that most stored water came from

  11. Microbial Activity in Forest Soil Under Beech, Spruce, Douglas Fir and Fir

    Directory of Open Access Journals (Sweden)

    Hajnal-Jafari Timea

    2016-08-01

    Full Text Available The aim of this research was to investigate the microbial activity in forest soil from different sites under deciduous and coniferous trees in Serbia. One site on Stara planina was under beech trees (Fagus sp. while another under mixture of spruce (Picea sp. and Douglas fir (Pseudotsuga sp.. The site on Kopaonik was under mixture of beech (Fagus sp. and spruce (Picea sp. trees. The site on Tara was dominantly under fir (Abies sp., beech (Fagus sp. and spruce (Picea sp.. The total number of bacteria, the number of actinobacteria, fungi and microorganisms involved in N and C cycles were determined using standard method of agar plates. The activities of dehydrogenase and ß-glucosidase enzymes were measured by spectrophotometric methods. The microbial activity was affected by tree species and sampling time. The highest dehydrogenase activity, total number of bacteria, number of actinobacteria, aminoheterotrophs, amylolytic and cellulolytic microorganisms were determined in soil under beech trees. The highest total number of fungi and number of pectinolytic microorganisms were determined in soil under spruce and Douglas fir trees. The correlation analyses proved the existence of statistically significant interdependency among investigated parameters.

  12. Pruning high-value Douglas-fir can reduce dwarf mistletoe severity and increase longevity in central Oregon

    Science.gov (United States)

    Maffei, Helen M; Filip, Gregory M; Gruelke, Nancy E; Oblinger, Brent W; Margolis, Ellis; Chadwick, Kristen L

    2016-01-01

    Mid- to very large-sized Douglas-fir (Pseudotsuga menzieseii var. menziesii) that were lightly- to moderately-infected by dwarf mistletoe (Arceuthobium douglasii) were analyzed over a 14-year period to evaluate whether mechanical pruning could eradicate mistletoe (or at least delay the onset of severe infection) without significantly affecting tree vitality and by inference, longevity. Immediate and longterm pruning effects on mistletoe infection severity were assessed by comparing pruned trees (n = 173) to unpruned trees (n = 55) with respect to: (1) percentage of trees with no visible infections 14 years post-pruning, (2) Broom Volume Rating (BVR), and (3) rate of BVR increase 14 years postpruning. Vitality/longevity (compared with unpruned trees) was assessed using six indicators: (1) tree survival, (2) the development of severe infections, (3) the development of dead tops, (4) tree-ring width indices, (5) Normalized Difference Vegetation Index (NDVI) from high-resolution multi-spectral imagery, and (6) live-crown ratio (LCR) and increment. Twenty-four percent of the pruned trees remained free of mistletoe 14 years post-pruning. Pruning is most likely to successfully eradicate mistletoe in lightly infected trees (BVR 1 or 2) without infected neighbors. Pruning significantly decreased mean BVR in the pruned versus the unpruned trees. However, the subsequent average rate of intensification (1.3–1.5 BVR per decade) was not affected, implying that a single pruning provides ~14 years respite in the progression of infection levels. Post-pruning infection intensification was slower on dominant and co-dominants than on intermediate or suppressed trees. The success of mistletoe eradication via pruning and need for follow-up pruning should be evaluated no sooner than 14 years after pruning to allow for the development of detectable brooms. Based on six indicators, foliage from witches brooms contribute little to long-term tree vitality since removal appears to have

  13. Impacts of Nitrogen Fertilization on Carbon and Water Balances in Different-aged Westcoast Douglas-fir Stands

    Science.gov (United States)

    Jassal, P.; Black, A.; Bruemmer, C.; Nesic, Z.; Spittlehouse, D.; Trofymow, T.

    2009-05-01

    Using the eddy-covariance technique, we have been measuring, since 1998, CO2, water vapour and energy exchange between the atmosphere and the ecosystem in three different-aged Westcoast Douglas-fir (Pseudotsuga menziesii) stands (9, 21 and 60 year-old in 2009, hereafter known as HDF00, HDF88 and DF49, respectively). These stands were fertilized with urea in January 2007. While HDF88 and DF49 were fertilized aerially with 200 kg N ha-1, HDF00, due to its young age and competing brush, was fertilized manually at 60 kg N ha-1. This paper reports the environmental controls of pre-fertilization interannual variability in ecosystem respiration (R), gross photosynthesis (P) and evapotranspiration (E), and discusses the effects of N- fertilization on these fluxes and net ecosystem productivity (NEP = P - R, i.e., carbon sequestration) and water use efficiency (WUE = P/E). For DF49, both pre-fertilization annual P and R responded positively to increases in mean annual air temperature and soil water content, but R was more responsive to both these environmental variables. Using these relationships, we calculated P and R for 2007 and 2008 assuming the stand was not fertilized. A comparison with measured 2007 and 2008 fluxes indicated that fertilization increased P and had almost no effect on R and soil respiration with the consequence that NEP was increased by 170 and 90 g C m- 2 during 2007 and 2008, respectively. Pre-fertilization annual E was modelled as a function of mean annual temperature, annual total photosynthetically active radiation, and precipitation for the previous year. Using this model to calculate 2007 and 2008 values of E for the unfertilized stand and comparing these with measured values in the fertilized stand indicated that fertilization had no effect on E, neither in 2007 nor in 2008. As a result, annual water use efficiency increased from a mean of 4.9 g C (kg water)-1 for 1998-2006 to 5.2 g C (kg water)-1 in 2007 and 2008. A similar analysis was

  14. Factors affecting diurnal stem contraction in young Douglas-fir

    Science.gov (United States)

    Warren D. Devine; Constance Harrington

    2011-01-01

    Diurnal fluctuation in a tree's stem diameter is a function of daily growth and of the tree's water balance, as water is temporarily stored in the relatively elastic outer cambial and phloem tissues. On a very productive site in southwestern Washington, U.S.A we used recording dendrometers to monitor stem diameter fluctuations of Douglas-fir at plantation...

  15. Predicting Douglas-fir's response to a warming climate

    Science.gov (United States)

    Andrea Watts; Sheel Bansal; Connie Harrington; Brad. St. Clair

    2015-01-01

    Douglas-fir is an iconic tree in the Pacific Northwest. Although individual trees may appear to be identical, genetic differences within each tree have resulted from adaptation to the local environment. These genetic differences over time have resulted in differences among populations that are important to the species' survival and growth in changing climates....

  16. Some economic considerations in thinning Douglas-fir.

    Science.gov (United States)

    Norman P. Worthington

    1957-01-01

    Many thousands of acres of young Douglas-fir stands in western Washington are ready for commercial thinning. This is true even after liberal allowance is made for premerchantable and under stocked stands, unfavorable topography, and lack of markets. However, with but few exceptions, regular systematic thinning is not being practiced even in favorably located, operable...

  17. Two commercial thinnings in century-old Douglas-fir.

    Science.gov (United States)

    Robert W. Steele

    1954-01-01

    As young-growth forests replace old-growth forests as the primary source of Douglas-fir raw material, the technique of managing young stands becomes increasingly important. Managers of young-growth timber need to know whether it is economical and silviculturally feasible to make thinnings in stands that are close to rotation age. Final harvest of some stands of this...

  18. Light thinning in century-old Douglas-fir.

    Science.gov (United States)

    Robert W. Steele

    1948-01-01

    A stand-improvement study in century-old Douglas-fir at the Wind River Experimental Forest provides an example of a commercial thinning that gave a substantial intermediate harvest, salvaged considerable material that would have been lost through mortality, greatly increased the net growth rate, and improved the general vigor of the stand, leaving the forest in a more...

  19. Response of individual Douglas-fir trees to release.

    Science.gov (United States)

    Donald L. Reukema

    1961-01-01

    To evaluate effects of different degrees of release on individual Douglas-fir trees, a study was started in 1952 in a 41-year-old, site IV stand at the Wind River Experimental Forest. A remeasurement at the end of four growing seasons showed that dominants respond more quickly and positively to the removal of competing trees than codominants or intermediates. A second...

  20. Reproduction following small group cuttings in virgin Douglas-fir.

    Science.gov (United States)

    Norman P. Worthington

    1953-01-01

    Quick and adequate regeneration of Douglas-fir forests as they are harvested is a major forest management problem in the Puget Sound region. Clear-cutting by staggered settings has not always resulted in adequate regeneration even where no part of the area is more than one-fourth mile from a seed source. Single tree selection, experimented with extensively, has many...

  1. Alteration of foliar flavonoid chemistry induced by enhanced UV-B radiation in field-grown Pinus ponderosa, Quercus rubra and Pseudotsuga menziesii.

    Science.gov (United States)

    Warren, Jeffrey M; Bassman, John H; Mattinson, D Scott; Fellman, John K; Edwards, Gerald E; Robberecht, Ronald

    2002-03-01

    Chromatographic analyses of foliage from several tree species illustrate the species-specific effects of UV-B radiation on both quantity and composition of foliar flavonoids. Pinus ponderosa, Quercus rubra and Pseudotsuga menziesii were field-grown under modulated ambient (1x) and enhanced (2x) biologically effective UV-B radiation. Foliage was harvested seasonally over a 3-year period, extracted, purified and the flavonoid fraction applied to a mu Bondapak/C(18) column HPLC system sampling at 254 nm. Total flavonoid concentrations in Quercus rubra foliage were more than twice (leaf area basis) that of the other species; Pseudotsuga menziesii foliage had intermediate levels and P. ponderosa had the lowest concentrations of total flavonoids. No statistically significant UV-B radiation-induced effects were found in total foliar flavonoid concentrations for any species; however, concentrations of specific compounds within each species exhibited significant treatment effects. Higher (but statistically insignificant) levels of flavonoids were induced by UV-B irradiation in 1- and 2-year-old P. ponderosa foliage. Total flavonoid concentrations in 2-year-old needles increased by 50% (1x ambient UV-B radiation) or 70% (2x ambient UV-B radiation) from that of 1-year-old tissue. Foliar flavonoids of Q. rubra under enhanced UV-B radiation tended to shift from early-eluting compounds to less polar flavonoids eluting later. There were no clear patterns of UV-B radiation effects on 1-year-old P. menziesii foliage. However, 2-year-old tissue had slightly higher foliar flavonoids under the 2x UV-B radiation treatment compared to ambient levels. Results suggest that enhanced UV-B radiation will alter foliar flavonoid composition and concentrations in forest tree species, which could impact tissue protection, and ultimately, competition, herbivory or litter decomposition.

  2. Effects of mountain beaver management and thinning on 15-year-old Douglas fir growth and survival.

    Science.gov (United States)

    Campbell, Dan L; Engeman, Richard M; Farley, James P

    2015-07-01

    We examined 4-year growth of 15-year-old damaged and undamaged Douglas fir (Pseudotsuga menzesii) after integrating temporary population reductions of mountain beaver (Aplodontia rufa) with thinning in a pre-commercial hand-planted plantation in western Washington. Five treatment combinations were considered: (1) trapping mountain beavers in an unthinned area, (2) trapping before thinning to 65 trees/ha (160 trees/ac), (3) no trapping and thinning to 65 trees/ha, (4) no trapping and thinning to 146 trees/ha (360 trees/ac), and (5) no trapping and no thinning. Removal of ≥ 90 % of mountain beavers temporarily reduced mountain beaver activity whether the stand was unthinned or thinned. Diameter growth at breast height (dbh) was greater for undamaged trees than for damaged trees in thinned areas. Tree height growth was greatest in trapped areas whether thinned or not. No differences were detected in 4-year survival between trees damaged aboveground and those without aboveground damage, which may be related to undetected root damage to trees without aboveground damage. Basal diameter growth and dbh growth were greatest for areas thinned to 65 trees/ha. Seventy-eight percent of stomachs from mountain beaver trapped in winter contained Douglas fir root or stem materials. Overall, short-term removal of mountain beavers integrated with pre-commercial thinning promoted growth of crop trees.

  3. Short-day treatment alters Douglas-fir seedling dehardening and transplant root proliferation at varying rhizosphere temperatures

    Science.gov (United States)

    Douglass F. Jacobs; Anthony S. Davis; BArrett C. Wilson; R. Kasten Dumroese; Rosa C. Goodman; K. Francis Salifu

    2008-01-01

    We tested effects of shortened day length during nursery culture on Douglis-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) seedling development at dormancy release. Seedlings from a 42 N source were grown either under ambient photoperiods (long-day (LD)) or with a 28 day period of 9 h light: 15 h dark photoperiods (short...

  4. Conversion of SPORL pretreated Douglas fir forest residues into microbial lipids with oleaginous yeasts

    Science.gov (United States)

    Bruce S. Dien; Junyong Zhu; Patricia J. Slininger; Cletus P. Kurtzman; Bryan R. Moser; Patricia J. O' Bryan; Roland Gleisner; Michael A. Cotta

    2016-01-01

    Douglas fir is the dominant commercial tree grown in the United States. In this study Douglas fir residue was converted to single cell oils (SCO) using oleaginous yeasts. Monosaccharides were extracted from the woody biomass by pretreating with sulfite and dilute sulfuric acid (SPORL process) and hydrolyzing using commercial cellulases. A new SPORL process that uses pH...

  5. Structural properties of laminated Douglas fir/epoxy composite material

    Energy Technology Data Exchange (ETDEWEB)

    Spera, D.A. (National Aeronautics and Space Administration, Cleveland, OH (USA). Lewis Research Center); Esgar, J.B. (Sverdrup Technology, Inc., Cleveland, OH (USA)); Gougeon, M.; Zuteck, M.D. (Gougeon Bros., Bay City, MI (USA))

    1990-05-01

    This publication contains a compilation of static and fatigue and strength data for laminated-wood material made from Douglas fir and epoxy. Results of tests conducted by several organizations are correlated to provide insight into the effects of variables such as moisture, size, lamina-to-lamina joint design, wood veneer grade, and the ratio of cyclic stress to steady stress during fatigue testing. These test data were originally obtained during development of wood rotor blades for large-scale wind turbines of the horizontal-axis (propeller) configuration. Most of the strength property data in this compilation are not found in the published literature. Test sections ranged from round cylinders 2.25 in. in diameter to rectangular slabs 6 in. by 24 in. in cross section and approximately 30 ft long. All specimens were made from Douglas fir veneers 0.10 in. thick, bonded together with the WEST epoxy system developed for fabrication and repair of wood boats. Loading was usually parallel to the grain. Size effects (reduction in strength with increase in test volume) are observed in some of the test data, and a simple mathematical model is presented that includes the probability of failure. General characteristics of the wood/epoxy laminate are discussed, including features that make it useful for a wide variety of applications. 9 refs.

  6. Stand-Level Gas-Exchange Responses to Seasonal Drought in Very Young Versus Old Douglas-fir Forests of the Pacific Northwest, USA

    Energy Technology Data Exchange (ETDEWEB)

    Wharton, S; Schroeder, M; Bible, K; Falk, M; Paw U, K T

    2009-02-23

    This study examines how stand age affects ecosystem mass and energy exchange response to seasonal drought in three adjacent Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests. The sites include two early seral stands (ES) (0-15 years old) and an old-growth (OG) ({approx} 450-500) forest in the Wind River Experiment Forest, Washington, USA. We use eddy covariance flux measurements of carbon dioxide (F{sub NEE}), latent energy ({lambda}E) and sensible heat (H) to derive evapotranspiration rate (E{sub T}), bowen ratio ({beta}), water use efficiency (WUE), canopy conductance (G{sub c}), the Priestley-Taylor coefficient ({alpha}) and a canopy decoupling factor ({Omega}). The canopy and bulk parameters are examined to see how ecophysiological responses to water stress, including changes in available soil water ({theta}{sub r}) and vapor pressure deficit ({delta}e) differ among the two forest successional-stages. Despite very different rainfall patterns in 2006 and 2007, we observed distinct successional-stage relationships between E{sub T}, {alpha}, and G{sub c} to {delta}e and {theta}{sub r} during both years. The largest stand differences were (1) higher morning G{sub c} (> 10 mm s{sup -1}) at the OG forest coinciding with higher CO{sub 2} uptake (F{sub NEE} = -9 to -6 {micro}mol m{sup -2} s{sup -1}) but a strong negative response in G{sub c} to moderate {delta}e later in the day and a subsequent reduction in E{sub T}, and (2) higher E{sub T} at the ES stands because midday canopy conductance did not decrease until very low water availability levels (<30%) were reached at the end of the summer. Our results suggest that early seral stands are more likely than mature forests to experience declines in production if the summer drought becomes longer or intensifies because water conserving ecophysiological responses were only observed at the very end of the seasonal drought period in the youngest stands.

  7. Leaf anatomical changes in Populus trichocarpa, Quercus rubra, Pseudotsuga menziesii and Pinus ponderosa exposed to enhanced ultraviolet-B radiation

    International Nuclear Information System (INIS)

    Nagel, L.M.; Bassman, J.H.; Edwards, G.E.; Robberecht, R.; Franceshi, V.R.

    1998-01-01

    Leaf anatomical characteristics are important in determining the degree of injury sustained when plants are exposed to natural and enhanced levels of ultraviolet-B (UV-B) radiation (280–320 nm). The degree to which leaf anatomy can adapt to the increasing levels of UV-B radiation reaching the earth's surface is poorly understood in most tree species. We examined four tree species, representing a wide range of leaf anatomical characteristics, to determine responses of leaf area, specific leaf weight, and leaf tissue parameters after exposure to ambient and enhanced levels of UV-B radiation. Seedlings were grown in a greenhouse with photosynthetically active radiation of 39 mol m −2 day −1 and under one of three daily irradiances of biologically effective UV-B radiation (UV-BBE) supplied for 10 h per day: (1) approximate ambient level received at Pullman, Washington on June 21 (1 x ); two times ambient (2 x ), or three times ambient (3 x ). We hypothesized the response of each species to UV-B radiation would be related to inherent anatomical differences. We found that the conifers responded anatomically to nearly an equal degree as the broad-leaved trees, but that different tissues were involved. Populus trichocarpa, an indeterminate broadleaf species, showed significantly thicker palisade parenchyma in recently mature leaves at the 3 x level and in older leaves under the 2 x level. In addition, individual leaf area was generally greater with increased UV-B irradiance. Quercus rubra, a semi-determinate broadleaf species, exhibited significantly thicker palisade parenchyma at the 2 x and 3 x levels as compared to controls. Psuedotsuga menziesii, an evergreen coniferous species with bifacially flattened needles, and Pinus ponderosa, an evergreen coniferous species with a complete hypodermis, showed no significant change in leaf area or specific leaf weight under enhanced UV-B radiation. Epidermal thickness was unchanged in P. menziesii. However, P. ponderosa

  8. A preliminary study of the deterioration of alder and Douglas-fir chips in outdoor piles.

    Science.gov (United States)

    Ernest. Wright

    1954-01-01

    In the fall of 1952, E. E. Matson of the Pacific Northwest Forest and Range Experiment Station learned that the Fir-Tex Insulating Board Company bf St. Helens, Oregon was considering mixing alder with Douglas-fir chips for outside storage. Since alder heartwood i s more susceptible to decay than that of Douglas-fir, the question arose whether mixing the two might...

  9. Early survival and growth of planted Douglas-fir with red alder in four mixed regimes.

    Science.gov (United States)

    Marshall D. Murray; Richard E. Miller

    1986-01-01

    To quantify between-species interactions, we measured and compared survival and growth of planted Douglas-fir and associated planted and volunteer red alder at a location on the west side of the Cascade Range in Washington. The planted alder were wildlings dug either from a nearby area or from a distant, coastal site and interplanted into a 3-year-old Douglas-fir...

  10. Deterioration of beetle-killed Douglas-fir in Oregon and Washington: a summary of findings to date.

    Science.gov (United States)

    Ernest Wright; K.H. Wright

    1954-01-01

    In 1952 and 1953 cooperative research was conducted by the Pacific Northwest Forest Experiment Station and the Research Department of Weyerhaeuser Timber Company to obtain information concerning the rate of deterioration of beetle-killed Douglas-fir. The study was prompted by an outbreak of the Douglas-fir beetle that developed in 1951 and has since killed an estimated...

  11. Effect of stand edge on the natural regeneration of spruce, beech and Douglas-fir

    Directory of Open Access Journals (Sweden)

    Lumír Dobrovolný

    2012-01-01

    Full Text Available Our work aimed at studying the strategy of woody plants regeneration during the regeneration of a spruce stand with the admixture of beech and Douglas-fir by border cutting (NW-SE aspect on acidic sites of higher elevations in the Bohemian-Moravian Upland. Spruce is better adapted to bear shade than Douglas-fir. Nevertheless, in optimal light conditions up to a distance of ca. 35 m (about 16% DIFFSF from the stand edge, the Douglas-fir can put the spruce into danger as to height growth. By contrast to beech, the density of spruce is significantly higher within the distance of 45 m (about 15% DIFFSF from the stand edge but further on the situation would change to the benefit of beech. The density of Douglas-fir significantly dominates over beech within a distance of 35 m from the stand edge; from 55 m (less than 15% DIFFSF, the situation changes in favour of beech. Beech can survive in full shade deep in the stand core waiting for its opportunity to come. As compared to spruce and Douglas-fir, the height growth of beech was at all times significantly greater at a distance of 25 m from the stand edge. Converted to practical conditions, spruce and Douglas-fir with individually admixed beech seedlings showed good prosperity approximately up to a distance of one stand height from the edge. A mixture of spruce and beech did well at a greater distance but good prosperity at a distance of 2–3 stand heights was shown only by beech. Thus, border regeneration eliminates disadvantages of the climatic extremes of clear-cutting and specifics of shelterwood felling during which one – usually shade-tolerant tree species dominates in the natural regeneration (e.g. beech.

  12. Phylogeographic analysis of the Douglas-fir beetle Dendroctonus pseudotsugae Hopkins (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    Enrico A. Ruíz; Jane L. Hayes; John E. Rinehart; G. Zúñiga

    2007-01-01

    Population genetic structure studies made in genus Dendroctonus have been conducted from the perspectives of allopatric and sympatric models. In the first case, host effect and historical contingency were not recognized as a source of variation, while the later considered the host itself as a source of reproductive isolation. Nevertheless, both...

  13. Management, morphological, and environmental factors influencing Douglas-fir bark furrows in the Oregon Coast Range

    Science.gov (United States)

    Sheridan, Christopher D.; Puettmann, Klaus J.; Huso, Manuela M.P.; Hagar, Joan C.; Falk, Kristen R.

    2013-01-01

    Many land managers in the Pacific Northwest have the goal of increasing late-successional forest structures. Despite the documented importance of Douglas-fir tree bark structure in forested ecosystems, little is known about factors influencing bark development and how foresters can manage development. This study investigated the relative importance of tree size, growth, environmental factors, and thinning on Douglas-fir bark furrow characteristics in the Oregon Coast Range. Bark furrow depth, area, and bark roughness were measured for Douglas-fir trees in young heavily thinned and unthinned sites and compared to older reference sites. We tested models for relationships between bark furrow response and thinning, tree diameter, diameter growth, and environmental factors. Separately, we compared bark responses measured on trees used by bark-foraging birds with trees with no observed usage. Tree diameter and diameter growth were the most important variables in predicting bark characteristics in young trees. Measured environmental variables were not strongly related to bark characteristics. Bark furrow characteristics in old trees were influenced by tree diameter and surrounding tree densities. Young trees used by bark foragers did not have different bark characteristics than unused trees. Efforts to enhance Douglas-fir bark characteristics should emphasize retention of larger diameter trees' growth enhancement.

  14. BOLE WATER CONTENT SHOWS LITTLE SEASONAL VARIATION IN CENTURY-OLD DOUGLAS-FIR TREES

    Science.gov (United States)

    Purportedly, large Douglas-fir trees in the American Pacific Northwest use water stored in bole tissues to ameliorate the effects of seasonal summer drought, the water content of bole tissues being drawn down over the summer months and replenished during the winter. Continuous mo...

  15. The economic significance of mortality in old-growth Douglas-fir management.

    Science.gov (United States)

    R.O. McMahon

    1961-01-01

    Current mortality in the Douglas-fir subregion, exclusive of catastrophic mortality, approximates a billion feet a year. The Forest Service report "Timber Resources for America's Future" recommended "...utilizing a substantial portion of the unsalvaged mortality loss..." as one means of permanently increasing the Nation's timber supply and...

  16. Lack of caching of direct-seeded Douglas fir seeds by deer mice

    International Nuclear Information System (INIS)

    Sullivan, T.P.

    1978-01-01

    Seed caching by deer mice was investigated by radiotagging seeds in forest and clear-cut areas in coastal British Columbia. Deer mice tend to cache very few Douglas fir seeds in the fall when the seed is uniformly distributed and is at densities comparable with those used in direct-seeding programs. (author)

  17. Regional patterns of increasing Swiss needle cast impacts on Douglas-fir growth with warming temperatures.

    Science.gov (United States)

    The fungal pathogen, Phaeocryptopus gaeumannii, occurs wherever Douglas-fir is found but disease damage is believed to be limited in the Pacific Northwest (PNW) to the Oregon Coast Range and is of no concern outside the coastal fog zone [1]. However, knowledge remains limited on...

  18. Estimating biomass of shrubs and forbs in central Washington Douglas-fir stands.

    Science.gov (United States)

    Craig M. Olson; Robert E. Martin

    1981-01-01

    Understory plants in closed 70-year-old even-aged Douglas-fir stands in north central Washington were destructively sampled to determine the relationship of ground cover and height to dry weight. Weight of plant material can be estimated from the product of plant height and percentage of ground cover on 50- x 100-centimeter (cm) quadrats. Correlation coefficients for...

  19. Nitrogen turnover in fresh Douglas fir litter directly after additions of moisture and inorganic nitrogen

    NARCIS (Netherlands)

    Raat, K.J.; Tietema, A.; Verstraten, J.M.

    2010-01-01

    The effects of wetting and drying and inorganic nitrogen (N) addition on carbon (C) and N turnover in fresh Douglas fir litter (Speuld forest, the Netherlands) were investigated. Litter was incubated for 9 days in the laboratory, receiving different moisture and N addition treatments. Following the

  20. Prescribed fire opportunities in grasslands invaded by Douglas-fir: state-of-the-art guidelines

    Science.gov (United States)

    George E. Gruell; James K. Brown; Charles L. Bushey

    1986-01-01

    Provides information on use of prescribed fire to enhance productivity of bunchgrass ranges that have been invaded by Douglas-fir. Six vegetative "situations" representative of treatment opportunities most commonly encountered in Montana are discussed. Included are fire prescription considerations and identification of the resource objective, fire objective,...

  1. Overstory response to alternative thinning treatments in young Douglas-fir forests of Western Oregon.

    Science.gov (United States)

    Liane R. Davis; Klaus J. Puettmann; Gabriel F. Tucker

    2007-01-01

    An increase in land dominated by young second-growth Douglas-fir forests in the Pacific Northwest has coincided with heightened concerns over loss of old-growth habitat. In search of options for managing young forests to provide late-successional forest structures, the Young Stand Thinning and Diversity Study was designed to test the effectiveness of modified thinning...

  2. Volume growth trends in a Douglas-fir levels-of-growing-stock study.

    Science.gov (United States)

    Robert O. Curtis

    2006-01-01

    Mean curves of increment and yield in gross total cubic volume and net merchantable cubic volume were derived from seven installations of the regional cooperative Levels-of-Growing-Stock Study (LOGS) in Douglas-fir. The technique used reduces the seven curves for each treatment for each variable of interest to a single set of readily interpretable mean curves. To a top...

  3. Pest management in Douglas-fir seed orchards: a microcomputer decision method

    Science.gov (United States)

    James B. Hoy; Michael I. Haverty

    1988-01-01

    The computer program described provides a Douglas-fir seed orchard manager (user) with a quantitative method for making insect pest management decisions on a desk-top computer. The decision system uses site-specific information such as estimates of seed crop size, insect attack rates, insecticide efficacy and application costs, weather, and crop value. At sites where...

  4. Nitrogen, corn, and forest genetics: the agricultural yield strategy-implications for Douglas-fir management.

    Science.gov (United States)

    Roy R. Silen

    1982-01-01

    Agricultural yield strategy simply aims to increase number of grain bearing stalks per acre. Forestry strategies look to thinning, fertilizer, and genetics, each to provide gains. The agricultural strategies applied to Douglas-fir appear to be impractical for long rotations. Concern is expressed for commitments to perpetual inputs of materials and energy to keep a...

  5. Foliar essential oils and deer browsing preference of Douglas-fir genotypes

    Science.gov (United States)

    M.A. Radwan

    1978-01-01

    Yield and composition of essential oils were compared in foliage of Douglas-fir. Five clones with different susceptibilities to deer browsing were used; foliage was collected during the dormant season. There were no qualitative differences among the oils of the different clones, but the oils differed quantitatively in all variables measured. Eight variables appeared...

  6. Effectiveness of fungicides in protecting Douglas-fir shoots from infection by Phytophthora ramorum

    Science.gov (United States)

    G.A. Chastagner; E.M. Hansen; K.L. Riley; W. Sutton

    2006-01-01

    The effectiveness of 20 systemic and contact fungicides in protecting Douglas-fir seedlings from infection by Phytophthora ramorum was determined. Some systemic products were applied about a week prior to bud break, while most treatments were applied just after bud break. In addition to the fungicides, two surfactants were included in the post-bud...

  7. Habitat management for red tree voles in Douglas-fir forests.

    Science.gov (United States)

    M.H. Huff; R.S. Holthausen; K.B. Aubry

    1992-01-01

    The relations between arboreal rodents and trees causes the animals to be particularly sensitive to the effects of timber harvesting.Among arboreal rodents,we consider the redtree vole to be the most vulnerable to local extinctions resulting from the loss or fragmentation of old-growth Douglas-fir forests. Redtree voles are nocturnal,canopy dwelling, and difficult to...

  8. Silvicultural research and the evolution of forest practices in the Douglas-fir region.

    Science.gov (United States)

    Robert O. Curtis; Dean S. DeBell; Richard E. Miller; Michael Newton; J. Bradley St. Clair; William I. Stein

    2007-01-01

    Silvicultural practices in the Douglas-fir region evolved through a combination of formal research, observation, and practical experience of forest managers and silviculturists, and changing economic and social factors. This process began more than a century ago and still continues. It has had a great influence on the economic well-being of the region and on the...

  9. Structural lumber from dense stands of small-diameter Douglas-fir trees.

    Science.gov (United States)

    David W. Green; Eini C. Lowell; Roland Hernandez

    2005-01-01

    Small-diameter trees growing in overstocked dense stands are often targeted for thinning to reduce fire hazard and improve forest health and ecosystem diversity. In the Pacific Northwest and Intermountain regions, Douglas-fir can be a predominant species in such stands. In this study, mechanical properties and grade yield of structural products were estimated for 2 by...

  10. Effects of water suspension and wet-dry cycling on fertility of Douglas-fir pollen.

    Science.gov (United States)

    Donald L. Copes; Nan C. Vance

    2000-01-01

    Studies were made to determine how long Douglas-fir pollen remains viable after suspension in cool water form 0 to 34 days. Linear regression analysis of in vivo and in vitro tests indicated that filled seed efficiency and pollen viability, respectively, decreased about 3 percent per day. The relation may have been nonlinear the first 6 days, as little decrease...

  11. Use of dominant tree heights in determining site index for Douglas-fir.

    Science.gov (United States)

    George R. Staebler

    1948-01-01

    Measuring heights of Douglas-fir trees for the determination of site index is a time-consuming job, especially in dense stands. Both dominant and codominant trees must be measured since site index curves represent the average height of dominants and codominants. It has been suggested that considerable time might be saved if only dominant trees were measured, since...

  12. Chemical composition of douglas-fir foliage on mule deer winter range. Research report No. RR 91003-CA

    Energy Technology Data Exchange (ETDEWEB)

    Waterhouse, M J; Armleder, H M; Dawson, R J

    1991-01-01

    In the interior of British Columbia, Douglas-fir litterfall is a major source of mule deer winter food. An earlier study found that preference for Douglas-fir foliage was correlated with tree diameter. This study identified the underlying factors of selection so that wildlife managers might have a wider range of forage enhancement options on mule deer winter range. Samples of Douglas-fir foliage were collected from trees at Knife Creek and Big Lake, and analyzed for minerals, tannins, and in vitro digestible dry matter.

  13. Effects of manganese and manganese-nitrogen applications on growth and nutrition of Douglas-fir seedlings.

    Science.gov (United States)

    M. A. Radwan; John S. Shumway; Dean S. DeBell

    1979-01-01

    Effects of manganese (Mn) on Douglas-fir grown in soil, with and without urea, and in nutrient solution were investigated. In addition, Mn sorption by forest soils was evaluated. Results show that Douglas-fir does not respond to added Mn and is quite tolerant to high Mn levels. Moreover, Mn sorption by soils is high. It is doubtful that Mn toxicity is of practical...

  14. Assessing the threat posed by indigenous exotics: A case study of two North American bark beetle species

    Science.gov (United States)

    K. J. Dodds; D. W. Gilmore; S. J. Seybold

    2010-01-01

    The Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, was detected in 2001 in northern Minnesota outside its natural range and the range of its native hosts, Douglas-fir, Pseudotsuga menziesii (Mirbel) Franco, and western larch, Larix occidentalis Nutt. Consecutive years of...

  15. Effects of biotic and abiotic factors on resistance versus resilience of Douglas fir to drought.

    Directory of Open Access Journals (Sweden)

    Gunnar Carnwath

    Full Text Available Significant increases in tree mortality due to drought-induced physiological stress have been documented worldwide. This trend is likely to continue with increased frequency and severity of extreme drought events in the future. Therefore, understanding the factors that influence variability in drought responses among trees will be critical to predicting ecosystem responses to climate change and developing effective management actions. In this study, we used hierarchical mixed-effects models to analyze drought responses of Pseudotsuga menziesii in 20 unmanaged forests stands across a broad range of environmental conditions in northeastern Washington, USA. We aimed to 1 identify the biotic and abiotic attributes most closely associated with the responses of individual trees to drought and 2 quantify the variability in drought responses at different spatial scales. We found that growth rates and competition for resources significantly affected resistance to a severe drought event in 2001: slow-growing trees and trees growing in subordinate canopy positions and/or with more neighbors suffered greater declines in radial growth during the drought event. In contrast, the ability of a tree to return to normal growth when climatic conditions improved (resilience was unaffected by competition or relative growth rates. Drought responses were significantly influenced by tree age: older trees were more resistant but less resilient than younger trees. Finally, we found differences between resistance and resilience in spatial scale: a significant proportion (approximately 50% of the variability in drought resistance across the study area was at broad spatial scales (i.e. among different forest types, most likely due to differences in the total amount of precipitation received at different elevations; in contrast, variation in resilience was overwhelmingly (82% at the level of individual trees within stands and there was no difference in drought resilience

  16. 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...

  17. Manipulating stand structure of Douglas-fir plantations for wildlife habitat and wood production

    Science.gov (United States)

    Timothy B. Harrington

    2010-01-01

    In southwestern Oregon, a study was initiated by Oregon State University (OSU) in 1983 to determine effects of hardwood competition on Douglas-fir plantation development. The use of herbicides to uniformly suppress competing vegetation—especially fast-growing hardwoods—proved to be an effective approach to ensure dominance and a high level of productivity for planted...

  18. Inheritance of germinative energy and germinative capacity in Douglas-fir

    Science.gov (United States)

    Thomas E. Greathouse

    1966-01-01

    In the West foresters have had considerable difficulty in reforesting south-facing slopes. We considered this problem when we selected plus-trees for the first Douglas-fir seed orchard in Region 6. We were, however, faced with the need to answer such questions as these: (1) Should we try to produce seed inherently suited for south slopes? (2) If so, should we strive to...

  19. Growth after precommercial thinning in two stands of Douglas-fir.

    Science.gov (United States)

    Robert W. Steele

    1955-01-01

    Twenty years ago, portions of two young Douglas-fir stands on the Wind River Experimental Forest in Skamania County, Washington, were thinned by removing some of the trees in the suppressed and intermediate crown classes. At time of thinning, one stand, (A), was 23 years old and the second, (B), was 30 years old. In both cases site quality is IV. The trees taken out...

  20. Plastic cages to protect Douglas-fir seedlings from animal damage in western Oregon.

    Science.gov (United States)

    Glen C. Crouch

    1980-01-01

    Effects of plastic mesh cages designed to protect Douglas-fir seedlings from animals were evaluated in western Oregon. In two tests over 5-year periods, caging increased survival by 0 and 13 percent and increased height growth by 0.8 and 1.2 feet compared with uncaged trees. Benefits from caging might have been greater if damage had been more prevalent during the tests...

  1. Automated knot detection with visual post-processing of Douglas-fir veneer images

    Science.gov (United States)

    C.L. Todoroki; Eini C. Lowell; Dennis Dykstra

    2010-01-01

    Knots on digital images of 51 full veneer sheets, obtained from nine peeler blocks crosscut from two 35-foot (10.7 m) long logs and one 18-foot (5.5 m) log from a single Douglas-fir tree, were detected using a two-phase algorithm. The algorithm was developed using one image, the Development Sheet, refined on five other images, the Training Sheets, and then applied to...

  2. Douglas-fir plantations in Europe: a retrospective test of assisted migration to address climate change.

    Science.gov (United States)

    Isaac-Renton, Miriam G; Roberts, David R; Hamann, Andreas; Spiecker, Heinrich

    2014-08-01

    We evaluate genetic test plantations of North American Douglas-fir provenances in Europe to quantify how tree populations respond when subjected to climate regime shifts, and we examined whether bioclimate envelope models developed for North America to guide assisted migration under climate change can retrospectively predict the success of these provenance transfers to Europe. The meta-analysis is based on long-term growth data of 2800 provenances transferred to 120 European test sites. The model was generally well suited to predict the best performing provenances along north-south gradients in Western Europe, but failed to predict superior performance of coastal North American populations under continental climate conditions in Eastern Europe. However, model projections appear appropriate when considering additional information regarding adaptation of Douglas-fir provenances to withstand frost and drought, even though the model partially fails in a validation against growth traits alone. We conclude by applying the partially validated model to climate change scenarios for Europe, demonstrating that climate trends observed over the last three decades warrant changes to current use of Douglas-fir provenances in plantation forestry throughout Western and Central Europe. © 2014 John Wiley & Sons Ltd.

  3. Using dendrochronology to detect and attribute CO2-induced growth increases in P. menziesii and P. ponderosa in western North America

    Science.gov (United States)

    Stretch, V.; Gedalof, Z.; Berg, A. A.

    2010-12-01

    Increased atmospheric CO2 could increase photosynthetic rates and cause trees to use water more efficiently, thereby increasing overall growth rates relative to climatic limiting factors. CO2 fertilization has been found across a range of forest types; however results have been inconsistent and based on short-term studies. Long-term studies based on tree-rings have generally been restricted to a few sites and have produced conflicting results. An initial global analysis of tree-ring widths for evidence of increasing growth relative to drought suggested a small but highly significant proportion of trees exhibit increasing growth over the past 130 years. These growth increases could not be attributed to increasing water use efficiency, elevation effects, nitrogen deposition, or divergence. These results suggest that CO2 fertilization is occurring at some locations and may influence future forest dynamics but this does not appear to occur at all locations. The processes causing differential responses are the focus of this study. Here we illustrate response differences between Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa). Using multiple site chronologies from these species over western North America, we demonstrate several site-specific explanations for differential responses to CO2 fertilization, such as forest composition, density, slope, aspect, soil type, and position relative to range limits.

  4. Silver fir and Douglas fir are more tolerant to extreme droughts than Norway spruce in south-western Germany

    Czech Academy of Sciences Publication Activity Database

    Vitali, V.; Büntgen, Ulf; Bauhus, J.

    2017-01-01

    Roč. 23, č. 12 (2017), s. 5108-5119 ISSN 1354-1013 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:86652079 Keywords : temperate forest trees * picea-abies karst. * climate- change * water relations * vosges mountains * growth-patterns * species stands * scots pine * alba * productivity * Abies alba * Central Europe * climate change * dendroecology * drought tolerance * forest management * Picea abies * Pseudotsuga menziesii Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 8.502, year: 2016

  5. Estimating seed crops of conifer and hardwood species

    Science.gov (United States)

    Philip M. McDonald

    1992-01-01

    Cone, acorn, and berry crops of ponderosa pine (Pinus ponderosa Dougl. ex Laws. var. ponderosa), sugar pine (Pinus lambertiana Dougl.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), California white fir (Abies concolor var. lowiana (Gord...

  6. Canopy structure and tree condition of young, mature, and old-growth Douglas-fir/hardwood forests

    Science.gov (United States)

    B.B. Bingham; J.O. Sawyer

    1992-01-01

    Sixty-two Douglas-fir/hardwood stands ranging from 40 to 560 years old were used to characterize the density; diameter, and height class distributions of canopy hardwoods and conifers in young (40 -100 yr), mature (101 - 200 yr) and old-growth (>200 yr) forests. The crown, bole, disease, disturbance, and cavity conditions of canopy conifers and hardwoods were...

  7. Relationship between canopy structure, microclimate, and Swiss needle cast severity among different ages of Douglas-fir forests

    Science.gov (United States)

    Swiss needle cast (SNC) is an endemic disease of Douglas-fir caused by Phaeocryptopus gaeumannii. The fungus infects newly emerged needles between May and August. As the fungus develops, its fruiting bodies (pseudothecia) block the stomata and inhibit gas exchange, reducing the p...

  8. The importance of seasonal temperature and moisture patterns on growth of Douglas-fir in western Oregon, USA

    Science.gov (United States)

    Douglas-fir growth in the Pacific Northwest is thought to be water limited. However, discerning the relative influence of air temperature and plant available soil water (W) on growth is difficult because they interact with each other, with other climate factors and with the inher...

  9. Regional effects of Swiss needle cast disease and climate on growth of Douglas-fir in western Oregon

    Science.gov (United States)

    The fungal pathogen, Phaeocryptopus gaeumannii, occurs wherever Douglas-fir is found but disease damage is believed to be limited to the Coast Range and is of no concern outside this region (Shaw et al., 2011). However, knowledge remains limited on the spatial distribution of Sw...

  10. Fire-mediated pathways of stand development in Douglas-fir/western hemlock forests of the Pacific Northwest, USA

    Science.gov (United States)

    A.J. Tepley; F.J. Swanson; T.A. Spies

    2013-01-01

    Forests dominated by Douglas-fir and western hemlock in the Pacific Northwest of the United States have strongly influenced concepts and policy concerning old-growth forest conservation. Despite the attention to their old-growth characteristics, a tendency remains to view their disturbance ecology in relatively simple terms, emphasizing infrequent, stand-replacing (SR...

  11. Fingerprints of a forest fungus: Swiss needle cast, carbon isotopes, carbohydrates, and growth in Douglas-fir

    Science.gov (United States)

    Andrea Watts; Frederick Meinzer; Brandy J. Saffell

    2014-01-01

    Swiss needle cast is caused by a fungus native to the Pacific Northwest. Its host is Douglas-fir, an iconic evergreen tree in the region. The fungus does not kill its host, but it adversely affects the tree's growth. The fungal fruiting bodies block the stomata, small openings on the underside of the needle where carbon dioxide, water vapor, and other gases are...

  12. A strategy for monitoring Swiss needle cast and assessing its growth impact in Douglas-fir plantations of Coastal Oregon

    Science.gov (United States)

    Doug Maguire; Alan Kanaskie; Mike McWilliams

    2000-01-01

    Many Douglas-fir plantations along the north coast of Oregon are exhibiting severe symptoms of Swiss needle cast disease (SNC). These symptoms include premature loss of foliage, abundant fungal pseudothecia on needles, yellowing of foliage, and apparent reduction in diameter and height growth. The development of the disease and its impacts on growth are currently being...

  13. Growth response of Douglas-fir seedlings to nitrogen fertilization: importance of Rubisco activation state and respiration rates.

    Science.gov (United States)

    Daniel K. Manter; Kathleen L. Kavanagh; Cathy L. Rose

    2005-01-01

    High foliar nitrogen concentration ([N]) is associated with high rates of photosynthesis and thus high tree productivity; however, at excessive [N], tree productivity is reduced. Reports of excessive [N] in the Douglas-fir forests of the Oregon Coast Range prompted this investigation of growth and needle physiological responses to increasing foliar N concentrations in...

  14. Timber supply in the Pacific Northwest: managing for economic and ecological values in Douglas-fir forest.

    Science.gov (United States)

    R.O. Curtis; A.B. Carey

    1996-01-01

    The Douglas-fir region of western Washington and Oregon and coastal British Columbia contains the most productive forestlands in North America. Yet disagreement among user groups and conflicting goals, policies, and laws have nearly paralyzed timber management on federal lands and greatly increased costs and complexity of management on nonfederal lands. Constructive...

  15. Slow and fast pyrolysis of Douglas-fir lignin: Importance of liquid-intermediate formation on the distribution of products

    NARCIS (Netherlands)

    Zhou, Shuai; Pecha, Brennan; van Kuppevelt, Michiel; McDonald, Armando G.; Garcia-Perez, Manuel

    2014-01-01

    The formation of liquid intermediates and the distribution of products were studied under slow and fast pyrolysis conditions. Results indicate that monomers are formed from lignin oligomeric products during secondary reactions, rather than directly from the native lignin. Lignin from Douglas-fir

  16. Seasonal carbohydrate dynamics and growth in Douglas-fir trees experiencing chronic, fungal-mediated reduction in functional leaf area

    Science.gov (United States)

    B. J. Saffell; F. C. Meinzer; D. R. Woodruff; D. C. Shaw; S. L. Voelker; B. Lachenbruch; K. Falk

    2014-01-01

    Stored non-structural carbohydrates (NSCs) could play an important role in tree survival in the face of a changing climate and associated stress-related mortality. We explored the effects of the stomata-blocking and defoliating fungal disease called Swiss needle cast on Douglas-fir carbohydrate reserves and growth to evaluate the extent to which NSCs can be mobilized...

  17. EFFECTS OF ELEVATED CO2 AND TEMPERATURE ON SOIL CARBON DENSITY FRACTIONS IN A DOUGLAS FIR MESOCOSM STUDY

    Science.gov (United States)

    We conducted a 4-year full-factorial study of the effects of elevated atmospheric CO2 and temperature on Douglas fir seedlings growing in reconstructed native forest soils in mesocosms. The elevated CO2 treatment was ambient CO2 plus 200 ppm CO2. The elevated temperature treatm...

  18. Genetic variation in tolerance of Douglas-fir to Swiss needle cast as assessed by symptom expression.

    Science.gov (United States)

    G.R. Jonhson

    2002-01-01

    The incidence of Swiss needle cast on Douglas-fir has increased significantly in recent years on the Oregon coast. Genetic variation in symptoms of disease infection, as measured by foliage traits, was assessed in two series of progeny trials to determine whether these "crown health" indicators were under genetic control and correlated with tolerance;...

  19. 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)....

  20. 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...

  1. Tree growth and soil relations at the 1925 Wind River spacing test in coast Douglas-fir.

    Science.gov (United States)

    Richard E. Miller; Donald L. Reukema; Harry W. Anderson

    2004-01-01

    The 1925 Wind River spacing test is the earliest field trial seeking to determine the most appropriate spacing for planting Douglas-fir. Spacing treatments were not replicated, although individual spacings were subsampled by two to four tree-measurement plots. Previously, greater growth occurred at the wider spacings (10 and 12 ft) than at the closer spacings (4, 5, 6...

  2. Regional patterns of increasing Swiss needle cast impacts on Douglas-fir growth with warming temperatures.

    Science.gov (United States)

    Lee, E Henry; Beedlow, Peter A; Waschmann, Ronald S; Tingey, David T; Cline, Steven; Bollman, Michael; Wickham, Charlotte; Carlile, Cailie

    2017-12-01

    The fungal pathogen, Phaeocryptopus gaeumannii , causing Swiss needle cast (SNC) occurs wherever Douglas-fir is found but disease damage is believed to be limited in the U.S. Pacific Northwest (PNW) to the Coast Range of Oregon and Washington (Hansen et al., Plant Disease , 2000, 84 , 773; Rosso & Hansen, Phytopathology , 2003, 93 , 790; Shaw, et al., Journal of Forestry , 2011, 109 , 109). However, knowledge remains limited on the history and spatial distribution of SNC impacts in the PNW. We reconstructed the history of SNC impacts on mature Douglas-fir trees based on tree-ring width chronologies from western Oregon. Our findings show that SNC impacts on growth occur wherever Douglas-fir is found and is not limited to the coastal fog zone. The spatiotemporal patterns of growth impact from SNC disease were synchronous across the region, displayed periodicities of 12-40 years, and strongly correlated with winter and summer temperatures and summer precipitation. The primary climatic factor limiting pathogen dynamics varied spatially by location, topography, and elevation. SNC impacts were least severe in the first half of the 20th century when climatic conditions during the warm phase of the Pacific Decadal Oscillation (1924-1945) were less conducive to pathogen development. At low- to mid-elevations, SNC impacts were most severe in 1984-1986 following several decades of warmer winters and cooler, wetter summers including a high summer precipitation anomaly in 1983. At high elevations on the west slope of the Cascade Range, SNC impacts peaked several years later and were the greatest in the 1990s, a period of warmer winter temperatures. Climate change is predicted to result in warmer winters and will likely continue to increase SNC severity at higher elevations, north along the coast from northern Oregon to British Columbia, and inland where low winter temperatures currently limit growth of the pathogen. Our findings indicate that SNC may become a significant

  3. Age-related variation in genetic control of height growth in Douglas-fir.

    Science.gov (United States)

    Namkoong, G; Usanis, R A; Silen, R R

    1972-01-01

    The development of genetic variances in height growth of Douglas-fir over a 53-year period is analyzed and found to fall into three periods. In the juvenile period, variances in environmental error increase logarithmically, genetic variance within populations exists at moderate levels, and variance among populations is low but increasing. In the early reproductive period, the response to environmental sources of error variance is restricted, genetic variance within populations disappears, and populational differences strongly emerge but do not increase as expected. In the later period, environmental error again increases rapidly, but genetic variance within populations does not reappear and population differences are maintained at about the same level as established in the early reproductive period. The change between the juvenile and early reproductive periods is perhaps associated with the onset of ecological dominance and significant allocations of energy to reproduction.

  4. Carbon dioxide flux measurements from a coastal Douglas-fir forest floor

    International Nuclear Information System (INIS)

    Drewitt, G.B.

    2002-01-01

    This thesis examined the process that affects the exchange of carbon between the soil and the atmosphere with particular attention to the large amounts of carbon stored in soils in the form of decaying organic matter. This forest floor measuring study was conducted in 2000 at a micro-meteorological tower flux site in a coastal temperature Douglas-fir forest. The measuring study involved half hourly measurements of both carbon dioxide and below-ground carbon dioxide storage. Measurements were taken at 6 locations between April and December to include a large portion of the growing season. Eddy covariance (EC) measurements of carbon dioxide flux above the forest floor over a two month period in the summer and the autumn were compared with forest floor measurements. Below-ground carbon dioxide mixing ratios of soil air were measured at 6 depths between 0.02 to 1 m using gas diffusion probes and a syringe sampling method. Maximum carbon dioxide fluxes measured by the soil chambers varied by a factor of 3 and a high spatial variability in soil carbon dioxide flux was noted. Forest floor carbon dioxide fluxes measured by each of the chambers indicated different sensitivities to soil temperature. Hysteresis in the flux temperature relationship over the year was evident. Reliable below-canopy EC measurements of the forest floor carbon dioxide flux were difficult to obtain because of the every low wind speeds below the forest canopy. The amount of carbon dioxde present in the soil increased rapidly with depth near the surface but less rapidly deeper in the soil. It was suggested that approximately half of the carbon dioxide produced below-ground comes from between the soil surface and the first 0.15 m of depth. Carbon dioxide fluxes from the floor of a Douglas-fir forest were found to be large compared to other, less productive ecosystems

  5. Five-Year Impacts of Swiss Needle Cast on Douglas-fir in Interior Forests of Oregon, USA

    Directory of Open Access Journals (Sweden)

    FILIP, Gregory

    2007-01-01

    Full Text Available In 2001 and 2006, we examined 590 Douglas-firs in 59 stands age 10-23 years in the northern Cascade Mountain foothills in Oregon, USA. Mean 5-year-dbh growth was 6.1 cm and total-height growth was 3.6 m. Mean needle-retention index increased by 3.4 over 5 years, and mid-crown retention increased by 1.2 years. Mean percentages of stomata occluded by pseudothecia of Phaeocryptopus gaeumannii were 13.6% for 2000-(2-year-old needles and 1.7% for 2001-(1-year-old needles sampled in 2002, and 13.3% for 2004 (2-year-old needles sampled in 2006. Mean crown-length to sapwood-area ratio was 5.2 cm/cm2 in 2006. There were poor correlations (R2 <0.3 among all variables except for a moderate correlation between stand elevation and either 2000-stomata occluded (R2 = 0.43 or 2004-stomata occluded (R2 = 0.50, where there were fewer pseudothecia at the higher elevations. Either 5 years is not enough time to evaluate the affects of Swiss needle cast on Douglas-fir growth in the Oregon Cascades or there was no significant effect of Swiss needle cast during the latest outbreak on Douglas-fir growth. Based on our results and their interpretation, forest managers may need not alter their current practices in the northern Oregon Cascades, and managing a mix of Douglas-fir and western hemlock at lower elevations and noble fir at higher elevations will help offset any future stand-growth declines due to Swiss needle cast.

  6. Volume and weight characteristics of a typical Douglas-fir/ western larch stand, Coram Experimental Forest, Montana

    Science.gov (United States)

    Robert E. Benson; Joyce A. Schlieter

    1980-01-01

    An over-mature Douglas-fir/western larch stand on the Coram Experimental Forest in Montana averaged about 7,300 ft3/acre (511 rn3/ha) of wood over 3 inches (7.62 cm) in diameter, and an additional 57 tons/acre (128/ha) of fine material, before harvest. After logging, using three different cutting methods and four different levels of utilization, wood residues ranged...

  7. Enhancement of Carbon Sequestration in west coast Douglas-fir Forests with Nitrogen Fertilization

    Science.gov (United States)

    Chen, B.; Jassal, R.; Black, A.; Brummer, C.; Spittlehouse, D.; Nesic, Z.

    2008-12-01

    Fertilization is one of the eligible management practices for C sequestering and hence reducing CO2 emissions under Article 3.4 of the Kyoto Protocol. In the coastal regions of British Columbia, which have very little nitrogen (N) deposition from pollution sources owing to their remote location, and soils deficient in N (Hanley et al., 1996), Douglas-fir stands respond to N fertilization (Brix, 1981; Fisher and Binkley, 2000; Chapin et al., 2002). However, a major concern with N fertilization is the potential loss from the soil surface of the highly potent greenhouse gas N2O, and little is known about such losses in N-fertilized forest soils. While it is necessary to determine and quantify the effects of N fertilization on stand C sequestration, it is also important to address environmental concerns by measuring N2O emissions to determine the net greenhouse gas (GHG) global warming potential (GWP). The GWP of N2O is 296 times (100-year time horizon) greater than that of CO2 (Ehhalt and Prather, 2001), yet there is little information on its net radiative forcing as a result of forest fertilization. We report two years of results on the effects of N fertilization in a chronosequence of three Douglas-fir stands (7, 19 and 58 years old, hereafter referred to as HDF00, HDF88 and DF49, respectively) on net C sequestration or net primary productivity measured using the eddy-covariance technique. DF49 (110 ha) and HDF88 (20 ha) were aerially fertilized with urea at 200 kg N ha-1 on Jan 13 and Feb 17, 2007, respectively, while due to its young age and competing understory, fertilizer to HDF00 (5 ha) was manually applied at 80 g urea/tree (60 kg N ha-1) along the tree drip line on Feb 13-14, 2007. Additionally, we calculate the net change in GHG GWP resulting from fertilization of DF49 by accounting for N2O emissions and energy costs of fertilizer production, transport, and application. We also compare polymer-coated slow-release urea (Environmentally Smart Nitrogen (ESN

  8. Monitoring soil chemical and physical parameters under Douglas fir in the Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Konsten, C.J.M.; Tiktak, A.; Bouten, W.

    1987-01-01

    In march 1987 a monitoring program started in two Douglas fir stands of different vitality in the Netherlands. Aim of the study is to provide insight in the chemical and physical rooting conditions of the vegetation and to quantify the contributions of atmospheric deposition to soil acidification. The hydrological part of the monitoring progam consists of automated measurements of precipitation, throughfall, soil water pressure head and soil water content; in addition soil water content is determined by neutron sonde measurements and gravimetry. These data are used as input data for simulation models which calculate water fluxes through the vegetation and soil. For the soil chemical part of the program precipitation (bulk and wet-only), throughfall and litter fall are sampled. The soil solution is sampled by suction from porous cups and from porous plates by a new, continous technique. Combination of soil chemical and soil physical data will result in chemical fluxes through the vegetation and through various soil compartments. Element budgets for the ecosystem will also be calculated. The program forms part of an interdisciplinary monitoring project within the Dutch Priority Programme on Acidification. 2 figs., 1 tab., 19 refs.

  9. Seasonal carbohydrate dynamics and growth in Douglas-fir trees experiencing chronic, fungal-mediated reduction in functional leaf area.

    Science.gov (United States)

    Saffell, Brandy J; Meinzer, Frederick C; Woodruff, David R; Shaw, David C; Voelker, Steven L; Lachenbruch, Barbara; Falk, Kristen

    2014-03-01

    Stored non-structural carbohydrates (NSCs) could play an important role in tree survival in the face of a changing climate and associated stress-related mortality. We explored the effects of the stomata-blocking and defoliating fungal disease called Swiss needle cast on Douglas-fir carbohydrate reserves and growth to evaluate the extent to which NSCs can be mobilized under natural conditions of low water stress and restricted carbon supply in relation to potential demands for growth. We analyzed the concentrations of starch, sucrose, glucose and fructose in foliage, twig wood and trunk sapwood of 15 co-occurring Douglas-fir trees expressing a gradient of Swiss needle cast symptom severity quantified as previous-year functional foliage mass. Growth (mean basal area increment, BAI) decreased by ∼80% and trunk NSC concentration decreased by 60% with decreasing functional foliage mass. The ratio of relative changes in NSC concentration and BAI, an index of the relative priority of storage versus growth, more than doubled with increasing disease severity. In contrast, twig and foliage NSC concentrations remained nearly constant with decreasing functional foliage mass. These results suggest that under disease-induced reductions in carbon supply, Douglas-fir trees retain NSCs (either actively or due to sequestration) at the expense of trunk radial growth. The crown retains the highest concentrations of NSC, presumably to maintain foliage growth and shoot extension in the spring, partially compensating for rapid foliage loss in the summer and fall.

  10. THE USE OF INTER SIMPLE SEQUENCE REPEATS (ISSR) IN DISTINGUISHING NEIGHBORING DOUGLAS-FIR TREES AS A MEANS TO IDENTIFYING TREE ROOTS WITH ABOVE-GROUND BIOMASS

    Science.gov (United States)

    We are attempting to identify specific root fragments from soil cores with individual trees. We successfully used Inter Simple Sequence Repeats (ISSR) to distinguish neighboring old-growth Douglas-fir trees from one another, while maintaining identity among each tree's parts. W...

  11. Levels-of-growing-stock cooperative study on Douglas-fir: report no. 02—The Hoskins Study, 1963-1970.

    Science.gov (United States)

    John F. Bell; Alan B. Berg

    1972-01-01

    Public and private agencies are cooperating in a study of eight thinning regimes in young Douglas-fir stands. Regimes differ in the amount of basal area allowed to accrue in growing stock at each successive thinning. All regimes start with a common level-of-growing-stock which is established by a conditioning thinning. Thinning interval is...

  12. SEASONAL PATTERNS AND VERTICAL PROFILE OF SOIL WATER UPTAKE AND UTILIZATION BY YOUNG AND OLD DOUGLAS-FIR AND PONDEROSA PINE FORESTS

    Science.gov (United States)

    Water availability has a strong influence on the distribution of forest tree species across the landscape. However, we do not understand how seasonal patterns of water utilization by tree species are related to their drought tolerance. In the Pacific Northwest, Douglas-fir occu...

  13. Patterns of Increasing Swiss Needle Cast Impacts on Growth of 20- and 40-year-old Douglas-fir from Tillamook

    Science.gov (United States)

    Currently, Swiss Needle Cast (SNC) is causing an epidemic west of the Oregon Coast Range from Coos Bay to Astoria. The most severely infected Douglas-fir trees are located on BLM land and Stimson Lumber plantations in Tillamook where environmental conditions are highly favorable ...

  14. Tree-ring history of Swiss needle cast impact on Douglas-fir growth in western Oregon: Correlations with climate variables

    Science.gov (United States)

    The fungal pathogen, Phaeocryptopus gaeumannii, occurs wherever Douglas-fir is found but disease damage is believed to be limited to the Coast Range and is of no concern outside the coastal fog zone (Shaw et al., 2011). However, knowledge remains limited on the history and spati...

  15. Effects of silviculture and genetics on branch/knot attributes of coastal Pacific Northwest Douglas-fir and implications for wood quality--a synthesis

    Science.gov (United States)

    Eini C. Lowell; Douglas A. Maguire; David G. Briggs; Eric C. Turnblom; Keith J.S. Jayawickrama; Jed. Bryce

    2014-01-01

    Douglas-fir is the most commercially important timber species in the US Pacific Northwest due to its ecological prevalence and its superior wood attributes, especially strength and stiffness properties that make it highly prized for structural applications. Its economic significance has led to extensive establishment and management of plantations over the last few...

  16. Levels-of-growing-stock cooperative study in Douglas-fir: report no. 08—The LOGS Study, 20-year results.

    Science.gov (United States)

    Robert O. Curtis; David D. Marshall

    1986-01-01

    This progress report reviews the history and status of the cooperative levels-of-growing-stock study in coast Douglas-fir, begun in 1961, in Oregon, Washington, and British Columbia. It presents new analyses, including comparisons among some installations. Data now available are primarily from the site II installations, which are approaching completion of the study....

  17. The relation between fine root density and proximity of stems in closed Douglas-fir plantations on homogen[e]ous sandy soils: implications for sampling design

    NARCIS (Netherlands)

    Olsthoorn, A.F.M.; Klap, J.M.; Oude Voshaar, J.H.

    1999-01-01

    Studies have been carried out in two fully stocked, fast growing Douglas-fir plantations of the Dutch ACIFORN project in three consecutive years, to obtain information on fine root densities (Olsthoorn 1991). For the present paper, data collected in early summer 1987 were used to study the relation

  18. The importance of amino sugar turnover to C and N cycling in organic horizons of old-growth Douglas-fir forest soils colonized by ectomycorrhizal mats

    Science.gov (United States)

    L. Zeglin; L.A. Kluber; D.D. Myrold

    2012-01-01

    Amino sugar dynamics represent an important but under-investigated component of the carbon (C) and nitrogen (N) cycles in old-growth Douglas-fir forest soils. Because fungal biomass is high in these soils, particularly in areas colonized by rhizomorphic ectomycorrhizal fungal mats, organic matter derived from chitinous cell wall material (or the monomeric building...

  19. Influences of climate, fire, and topography on contemporary age structure patterns of Douglas-fir at 205 old forest sites in western Oregon

    Science.gov (United States)

    Nathan J. Poage; Peter J. Weisberg; Peter C. Impara; John C. Tappeiner; Thomas S. Sensenig

    2009-01-01

    Knowledge of forest development is basic to understanding the ecology, dynamics, and management of forest ecosystems. We hypothesized that the age structure patterns of Douglas-fir at 205 old forest sites in western Oregon are extremely variable with long and (or) multiple establishment periods common, and that these patterns reflect variation in regional-scale climate...

  20. Monitoring larval populations of the Douglas-fir tussock moth and the western spruce budworm on permanent plots: sampling methods and statistical properties of data

    Science.gov (United States)

    A.R. Mason; H.G. Paul

    1994-01-01

    Procedures for monitoring larval populations of the Douglas-fir tussock moth and the western spruce budworm are recommended based on many years experience in sampling these species in eastern Oregon and Washington. It is shown that statistically reliable estimates of larval density can be made for a population by sampling host trees in a series of permanent plots in a...

  1. Early survival and height growth of Douglas-fir and lodgepole pine seedlings and variations in site factors following treatment of logging residues.

    Science.gov (United States)

    W. Lopushlnsky; D. Zabowskl; T.D. Anderson

    1992-01-01

    Logging residues were broadcast burned, piled and burned, removed, or left in place after clearcutting in a high-elevation subalpine fir (Abies lasiocarpa (Hook.) Nutt.) lodgepole pine (Pinus contorta Dougl. ex Loud.) forest in north-central Washington. Survival, height growth and foliar nutrient content of planted Douglas-fir...

  2. Using sulfite chemistry for robust bioconversion of Douglas-fir forest residue to bioethanol at high titer and lignosulfonate: A pilot-scale evaluation

    Science.gov (United States)

    J.Y. Zhu; M. Subhosh Chandra; Feng Gu; Roland Gleisner; J.Y. Zhu; John Sessions; Gevan Marrs; Johnway Gao; Dwight Anderson

    2015-01-01

    This study demonstrated at the pilot-scale (50 kg) use of Douglas-fir forest harvest residue, an underutilized forest biomass, for the production of high titer and high yield bioethanol using sulfite chemistry without solid–liquor separation and detoxification. Sulfite Pretreatment to Overcome the Recalcitrance of Lignocelluloses (SPORL) was directly applied to the...

  3. Eco-physiological characteristics and variation in water source use between montane Douglas-Fir and lodgepole pine trees in southwestern Alberta

    Science.gov (United States)

    Andrews, S.; Flanagan, L. B.

    2009-12-01

    Winter weather on the Canadian prairies is now warmer and drier than 50 years ago and this has implications for soil water re-charge in montane ecosystems with consequences for tree and ecosystem function. We used measurements of the hydrogen isotope ratio of tree stem water to analyze the use of different water sources (winter snow melt, ground water, summer precipitation) in two montane forest sites, one dominated by Douglas-Fir and the other dominated by lodgepole pine trees. On average during the growing season (May-October) stem water in both Douglas-Fir and lodgepole pine trees was composed of 60% summer precipitation. However, during late summer Douglas-Fir trees showed an increased use of ground water as summer precipitation was minimal and ground water was accessible at the bottom of a relatively large soil reservoir. The low summer precipitation and reduced soil water availability in the shallow soils at the lodgepole pine site resulted in severely reduced photosynthetic capacity in late summer. Increased precipitation during the autumn resulted in recovery of photosynthetic gas exchange in lodgepole pine before winter dormancy was induced by low temperatures. Stomatal limitation of photosynthesis, as estimated from measurements of the carbon isotope composition of leaf tissue, was higher in Douglas-Fir than lodgepole pine. This was also associated with lower midday water potential values in Douglas-Fir and sapwood cross-sectional area that was only 70% of that measured in lodgepole pine. The vulnerability of xylem to loss of conductivity with declines in water potential was very similar between the two species. However, midday water potential in Douglas-Fir approached values where cavitation and loss of conductivity were apparent, while in lodgepole pine midday water potential was always much higher than the point at which loss of hydraulic conductivity occurred. These data suggest that, despite the presence of Douglas-Fir on deeper and higher quality

  4. Stand characteristics of 65-year-old planted and naturally regenerated stands near Sequim, Washington.

    Science.gov (United States)

    Richard E. Miller; Harry W. Anderson

    1995-01-01

    Tree numbers, height, and volume were determined in six 63- to 66-year-old plantations of coast Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) in northwest Washington. These stands resulted from the first extensive plantings of this species in the Pacific Northwest. Data from 0.25-acre plots in these...

  5. Uptake of 15N labelled urea and ammonium nitrate by 4-year old Douglas-fir grown in sand-peat mix

    International Nuclear Information System (INIS)

    Pang, P.C.K.

    1982-01-01

    Four-year old Douglas-fir planted in a 1:1 ratio of sand and peat mixture were fertilized with 200 kg N/ha in the form of either ( 15 NH 2 ) 2 CO, 15 NH 4 NO 3 or NH 4 15 NO 3 and grown in a shadehouse over periods of one and two years. Under the experimental conditions, trees recovered a higher percentage of 15 N from the NO 3 - than the NH 4 + source. The soil retained a higher percentage of N from NH 4 + than the NO 3 - source. % Ndff suggested NO 3 - is the preferred N source for the Douglas-fir. A description is also given of some of the ongoing experiments related to N fertilization of forests underway at the Pacific Forest Research Centre. (author)

  6. Investigation of the particle size distribution and particle density characteristics of Douglas fir hogged fuel fly ash collected under known combustion conditions. Technical Progress Report No. 2

    Energy Technology Data Exchange (ETDEWEB)

    Lang, A.J.; Junge, D.C.

    1978-12-01

    The increased interest in wood as a fuel source, coupled with the increasing demand to control the emission generated by wood combustion, has created a need for information characterizing the emissions that occur for given combustion conditions. This investigation characterizes the carbon char and inorganic fly ash size and density distribution for each of thirty-eight Douglas fir bark samples collected under known conditions of combustion.

  7. Biomass conversion and expansion factors in Douglas-fir stands of different planting density: variation according to individual growth and prediction equations

    International Nuclear Information System (INIS)

    Marziliano, P.A.; Menguzzato, G.; Scuderi, A.; Scalise, C.; Coletta, V.

    2017-01-01

    Aim of study: We built biomass expansion factors (BCEFs) from Douglas-fir felled trees planted with different planting densities to evaluate the differences according tree size and planting density. Area of study: The Douglas-fir plantation under study is located on the northern coastal chain of Calabria (Tyrrhenian side) south Italy. Materials and methods: We derived tree level BCEFs, relative to crown (BCEFc), to stem (BCEFst = basic density, BD) and total above-ground (BCEFt) from destructive measurements carried out in a Douglas-fir plantation where four study plots were selected according to different planting densities (from 833 to 2500 trees per hectare). The measured BCEFs were regressed against diameter at breast height and total height, planting density, site productivity (SP) and their interactions to test the variation of BCEFs. Analysis of variance (ANOVA) and the post hoc Tukey comparison test were used to test differences in BCEFt, BCEFc and in BD between plots with different planting density. Main results: BCEFs decreased with increasing total height and DBH, but large dispersion measures were obtained for any of the compartments in the analysis. An increasing trend with planting density was found for all the analyzed BCEFs, but together with planting density, BCEFs also resulted dependent upon site productivity. BCEFt average values ranged between 1.40 Mg m-3 in planting density with 833 trees/ha (PD833) to 2.09 Mg m-3 in planting density with 2500 trees/ha (PD2500), which are in the range of IPCC prescribed values for Douglas-fir trees. Research highlights: Our results showed that the application of BCEF to estimate forest biomass in stands with different planting densities should explicitly account for the effect of planting density and site productivity.

  8. Biomass conversion and expansion factors in Douglas-fir stands of different planting density: variation according to individual growth and prediction equations

    Energy Technology Data Exchange (ETDEWEB)

    Marziliano, P.A.; Menguzzato, G.; Scuderi, A.; Scalise, C.; Coletta, V.

    2017-11-01

    Aim of study: We built biomass expansion factors (BCEFs) from Douglas-fir felled trees planted with different planting densities to evaluate the differences according tree size and planting density. Area of study: The Douglas-fir plantation under study is located on the northern coastal chain of Calabria (Tyrrhenian side) south Italy. Materials and methods: We derived tree level BCEFs, relative to crown (BCEFc), to stem (BCEFst = basic density, BD) and total above-ground (BCEFt) from destructive measurements carried out in a Douglas-fir plantation where four study plots were selected according to different planting densities (from 833 to 2500 trees per hectare). The measured BCEFs were regressed against diameter at breast height and total height, planting density, site productivity (SP) and their interactions to test the variation of BCEFs. Analysis of variance (ANOVA) and the post hoc Tukey comparison test were used to test differences in BCEFt, BCEFc and in BD between plots with different planting density. Main results: BCEFs decreased with increasing total height and DBH, but large dispersion measures were obtained for any of the compartments in the analysis. An increasing trend with planting density was found for all the analyzed BCEFs, but together with planting density, BCEFs also resulted dependent upon site productivity. BCEFt average values ranged between 1.40 Mg m-3 in planting density with 833 trees/ha (PD833) to 2.09 Mg m-3 in planting density with 2500 trees/ha (PD2500), which are in the range of IPCC prescribed values for Douglas-fir trees. Research highlights: Our results showed that the application of BCEF to estimate forest biomass in stands with different planting densities should explicitly account for the effect of planting density and site productivity.

  9. Interactions of predominant insects and diseases with climate change in Douglas-fir forests of western Oregon and Washington, U.S.A.

    Science.gov (United States)

    Agne, Michelle C; Beedlow, Peter A; Shaw, David C; Woodruff, David R; Lee, E Henry; Cline, Steven P; Comeleo, Randy L

    2018-02-01

    Forest disturbance regimes are beginning to show evidence of climate-mediated changes, such as increasing severity of droughts and insect outbreaks. We review the major insects and pathogens affecting the disturbance regime for coastal Douglas-fir forests in western Oregon and Washington State, USA, and ask how future climate changes may influence their role in disturbance ecology. Although the physiological constraints of light, temperature, and moisture largely control tree growth, episodic and chronic disturbances interacting with biological factors have substantial impacts on the structure and functioning of forest ecosystems in this region. Understanding insect and disease interactions is critical to predicting forest response to climate change and the consequences for ecosystem services, such as timber, clean water, fish and wildlife. We focused on future predictions for warmer wetter winters, hotter drier summers, and elevated atmospheric CO 2 to hypothesize the response of Douglas-fir forests to the major insects and diseases influencing this forest type: Douglas-fir beetle, Swiss needle cast, black stain root disease, and laminated root rot. We hypothesize that 1) Douglas-fir beetle and black stain root disease could become more prevalent with increasing, fire, temperature stress, and moisture stress, 2) future impacts of Swiss needle cast are difficult to predict due to uncertainties in May-July leaf wetness, but warmer winters could contribute to intensification at higher elevations, and 3) laminated root rot will be influenced primarily by forest management, rather than climatic change. Furthermore, these biotic disturbance agents interact in complex ways that are poorly understood. Consequently, to inform management decisions, insect and disease influences on disturbance regimes must be characterized specifically by forest type and region in order to accurately capture these interactions in light of future climate-mediated changes.

  10. Metal stress and decreased tree growth in response to biosolids application in greenhouse seedlings and in situ Douglas-fir stands

    International Nuclear Information System (INIS)

    Cline, Erica T.; Nguyen, Quyen T.N.; Rollins, Lucy; Gawel, James E.

    2012-01-01

    To assess physiological impacts of biosolids on trees, metal contaminants and phytochelatins were measured in Douglas-fir stands amended with biosolids in 1982. A subsequent greenhouse study compared these same soils to soils amended with fresh wastewater treatment plant biosolids. Biosolids-amended field soils had significantly higher organic matter, lower pH, and elevated metals even after 25 years. In the field study, no beneficial growth effects were detected in biosolids-amended stands and in the greenhouse study both fresh and historic biosolids amendments resulted in lower seedling growth rates. Phytochelatins – bioindicators of intracellular metal stress – were elevated in foliage of biosolids-amended stands, and significantly higher in roots of seedlings grown with fresh biosolids. These results demonstrate that biosolids amendments have short- and long-term negative effects that may counteract the expected tree growth benefits. - Highlights: ► Biosolids amendment increases soil metals over 25 years later. ► Douglas-fir growth benefits fail to materialize from biosolids amendments. ► Phytochelatins are elevated in foliage of trees and roots of greenhouse seedlings after new biosolids are added to soil. ► Biosolids connected to metal stress in Douglas-fir. - Biosolids applications increase bioindicators of intracellular metal stress and may counteract tree growth benefits.

  11. Two-Step Hot-Compressed Water Treatment of Douglas Fir for Efficient Total Sugar Recovery by Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Hiroyuki Inoue

    2016-04-01

    Full Text Available The non-catalytic hydrothermal pretreatment of softwood is generally less effective for subsequent enzymatic hydrolysis. In this study, the efficacy of hot-compressed water (HCW treatment of Douglas fir was investigated between 180 °C and 260 °C, allowing solubilization of the cellulose components. The enzymatic digestibility of cellulosic residues increased significantly under HCW conditions > 250 °C, and the enhanced glucan digestibility was closely related to the decomposition of the cellulose component. Combination of the first-stage HCW treatment (220 °C, 5 min to recover hemicellulosic sugars with the second-stage HCW treatment (260 °C, 5 min to improve cellulose digestibility gave a total sugar recovery of 56.2% based on the dried raw materials. This yield was 1.4 times higher than that from the one-step HCW-treated sample (260 °C, 5 min. Additionally, an enzymatic hydrolysate from the two-step HCW-treated sample exceeded 90% of the ethanol fermentation yield based on the total sugars present in the hydrolysates. These results suggest the potential of the two-step HCW treatment of softwood as a pretreatment technology for efficient total sugar recovery and ethanol production.

  12. Thinning of young Douglas-fir forests decreases density of northern flying squirrels in the Oregon Cascades

    Science.gov (United States)

    Manning, Tom; Hagar, Joan C.; McComb, Brenda C.

    2012-01-01

    Large-scale commercial thinning of young forests in the Pacific Northwest is currently promoted on public lands to accelerate the development of late-seral forest structure for the benefit of wildlife species such as northern spotted owls (Strix occidentalis caurina) and their prey, including the northern flying squirrel (Glaucomys sabrinus). Attempts to measure the impact of commercial thinning on northern flying squirrels have mostly addressed short-term effects (2–5 years post-thinning) and the few published studies of longer-term results have been contradictory. We measured densities of northern flying squirrels 11–13 years after thinning of young (55–65 years) Douglas-fir forest stands in the Cascade Range of Oregon, as part of the Young Stand Thinning & Diversity Study. The study includes four replicate blocks, each consisting of an unthinned control stand and one stand each of the following thinning treatments: Heavy Thin; Light Thin; and Light Thin with Gaps. Thinning decreased density of northern flying squirrels, and squirrel densities were significantly lower in heavily thinned stands than in more lightly thinned stands. Regression analysis revealed a strong positive relationship of flying squirrel density with density of large (>30 cm diameter) standing dead trees and a negative relationship with percent cover of low understory shrubs. Maintaining sufficient area and connectivity of dense, closed canopy forest is recommended as a strategy to assure that long-term goals of promoting late-seral structure do not conflict with short-term habitat requirements of this important species.

  13. Variation in short-term and long-term responses of photosynthesis and isoprenoid-mediated photoprotection to soil water availability in four Douglas-fir provenances.

    Science.gov (United States)

    Junker, Laura Verena; Kleiber, Anita; Jansen, Kirstin; Wildhagen, Henning; Hess, Moritz; Kayler, Zachary; Kammerer, Bernd; Schnitzler, Jörg-Peter; Kreuzwieser, Jürgen; Gessler, Arthur; Ensminger, Ingo

    2017-01-10

    For long-lived forest tree species, the understanding of intraspecific variation among populations and their response to water availability can reveal their ability to cope with and adapt to climate change. Dissipation of excess excitation energy, mediated by photoprotective isoprenoids, is an important defense mechanism against drought and high light when photosynthesis is hampered. We used 50-year-old Douglas-fir trees of four provenances at two common garden experiments to characterize provenance-specific variation in photosynthesis and photoprotective mechanisms mediated by essential and non-essential isoprenoids in response to soil water availability and solar radiation. All provenances revealed uniform photoprotective responses to high solar radiation, including increased de-epoxidation of photoprotective xanthophyll cycle pigments and enhanced emission of volatile monoterpenes. In contrast, we observed differences between provenances in response to drought, where provenances sustaining higher CO 2 assimilation rates also revealed increased water-use efficiency, carotenoid-chlorophyll ratios, pools of xanthophyll cycle pigments, β-carotene and stored monoterpenes. Our results demonstrate that local adaptation to contrasting habitats affected chlorophyll-carotenoid ratios, pool sizes of photoprotective xanthophylls, β-carotene, and stored volatile isoprenoids. We conclude that intraspecific variation in isoprenoid-mediated photoprotective mechanisms contributes to the adaptive potential of Douglas-fir provenances to climate change.

  14. Killing tanoak in northwestern California

    Science.gov (United States)

    D. F. Roy

    1956-01-01

    Residual tanoak (Lithocarpus densiflorus (Hook. & Arn.) Rehd.) trees and tanoak sprouts often are an important component of the vegetation which competes with conifer reproduction in northwestern California. Sometimes enough tanoak is present in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands to dominate the...

  15. Effects of plantation and juvenile spacing on tree and stand development.

    Science.gov (United States)

    J. Harry G. Smith; Donald L. Reukema

    1986-01-01

    The aim of this paper is to summarize current knowledge of effects of initial spacing and respacing of plantations and natural stands on early growth until the time of first commercial entry—for coastal Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco), concentrating on conclusions that can be drawn from the literature and the authors...

  16. Nitrogen leaching following whole-tree and bole-only harvests on two contrasting Pacific Northwest sites

    Science.gov (United States)

    Warren D. Devine; Paul W. Footen; Brian D. Strahm; Robert B. Harrison; Thomas A. Terry; Timothy B. Harrington

    2012-01-01

    Short-term pulses of increased N leaching typically follow the harvest of forest stands, but the magnitude of these pulses after conventional bole-only (BO) and whole-tree (WT) harvests often is difficult to predict. In this study, we measured N leaching until 6 and 8 years post-harvest on two western Washington Douglas-fir (Pseudotsuga menziesii...

  17. Simulating fuel treatment effects in dry forests of the western United States: testing the principles of a fire-safe forest

    Science.gov (United States)

    Morris C. Johnson; Maureen C Kennedy; David L. Peterson

    2011-01-01

    We used the Fire and Fuels Extension to the Forest Vegetation Simulator (FFE-FVS) to simulate fuel treatment effects on stands in low- to midelevation dry forests (e.g., ponderosa pine (Pinus ponderosa Dougl. ex. P. & C. Laws.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) of the western United States. We...

  18. 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...

  19. Cherry Creek Research Natural Area: guidebook supplement 41

    Science.gov (United States)

    Reid Schuller; Jennie Sperling; Tim Rodenkirk

    2011-01-01

    This guidebook describes Cherry Creek Research Natural Area, a 239-ha (590-ac) area that supports old-growth Douglas-fir-western hemlock (Pseudotsuga menziesii- Tsuga heterophylla) forest occurring on sedimentary materials in the southern Oregon Coast Range. Major plant associations present within the area include the western hemlock/Oregon oxalis...

  20. Parental GCA testing: how many crosses per parent?

    Science.gov (United States)

    G.R. Johnson

    1998-01-01

    The impact of increasing the number of crosses per parent (k) on the efficiency of roguing seed orchards (backwards selection, i.e., reselection of parents) was examined by using Monte Carlo simulation. Efficiencies were examined in light of advanced-generation Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) tree improvement programs where...

  1. 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...

  2. Some lessons in artificial regeneration from southwestern Oregon.

    Science.gov (United States)

    William I. Stein

    1955-01-01

    Natural reproduction has often proved undependable for restocking cutovers and burns in the mixed-conifer forest types of southwestern Oregon. These types, covering 6,000 square miles of productive forest land in the five southwestern Oregon counties, are composed of many species--principally Douglas fir, Pseudotsuga menziesii (Mirb.) Franco;...

  3. Realistic Bomber Training Initiative. Environmental Impact Statement. Volume 1

    Science.gov (United States)

    2000-01-01

    arizonica Bitterweed Hymenoxys odorata Black grama Bouteloua eriopoda Broadleaf milkweed Ascelpias latifolia Broomweed Amphiachyris spp. and...Larrea tridentata Douglas fir Pseudotsuga menziesii Fragrant ash Fraxinus cuspidata Galleta grass Hilaria jamesii Gambel (=shin) oak Quercus gambelii...Guajillo Acacia berlandieri Juniper Juniperus spp. Little bluestem Schizachyrium scoparium Live oak Quercus turbinella Mesquite Prosopis spp. Mexican

  4. Stress Wave E-Rating of Structural Timber—Size and Moisture Content Effects

    Science.gov (United States)

    Xiping Wang

    2013-01-01

    The objectives of this study were to investigate the influence of cross sectional size and moisture content on stress wave properties of structural timber in various sizes and evaluate the feasibility of using stress wave method to E-rate timber in green conditions. Four different sizes of Douglas-fir (Pseudotsuga menziesii) square timbers were...

  5. Climate-related trends in sapwood biophysical properties in two conifers: avoidance of hydraulic dysfunction through coordinated adjustments in xylem efficiency, safety and capacitance

    Science.gov (United States)

    David M. Barnard; Frederick C. Meinzer; Barbara Lachenbruch; Katherine A. McCulloh; Daniel M. Johnson; David R. Woodruff

    2011-01-01

    In the Pacific north-west, the Cascade Mountain Range blocks much of the precipitation and maritime influence of the Pacific Ocean, resulting in distinct climates east and west of the mountains. The current study aimed to investigate relationships between water storage and transport properties in populations of Douglas-fir (Pseudotsuga menziesii)...

  6. Soil compaction and organic matter affect conifer seedling nonmycorrhizal and ectomycorrhizal root tip abundance and diversity.

    Science.gov (United States)

    Michael P. Amaranthus; Debbie Page-Dumroese; Al Harvey; Efren Cazares; Larry F. Bednar

    1996-01-01

    Three levels of organic matter removal (bole only; bole and crowns; and bole, crowns, and forest floor) and three levels of mechanical soil compaction (no compaction, moderate compaction, and severe soil compaction) were studied as they influence Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) and western white...

  7. Breeding birds in riparian and upland dry forests of the Cascade Range

    Science.gov (United States)

    John F. Lehmkuhl; E. Dorsey Burger; Emily K. Drew; John P. Lindsey; Maryellen Haggard; Kent Z. Woodruff

    2007-01-01

    We quantified breeding bird abundance, diversity, and indicator species in riparian and upland dry forests along six third- to fourth-order streams on the east slope of the Cascade Range, Washington, USA. Upland mesic forest on southerly aspects was dominated by open ponderosa pine (Pinus ponderosa) and dry Douglas-fir (Pseudotsuga menziesii...

  8. Riparian microclimate and stream temperature: thinning and buffer-width influences

    Science.gov (United States)

    Paul D. Anderson

    2013-01-01

    Th inning of 30- to 70-year-old Douglas-fir (Pseudotsuga menziesii) stands is a common silvicultural activity on federal forest lands in Washington and Oregon west of the Cascade Range crest. Decreases in forest cover lead to alterations of site energy balances resulting in changes to understory and stream channel microclimates. Uncut vegetative...

  9. Soil disturbance assessment of a cable logging operation performing five silvicultural prescriptions

    Science.gov (United States)

    John Klepac; Steve Reutebuch

    2003-01-01

    Evaluating alternative methods for regenerating second-growth Douglas-fir (Pseudotsuga menziesii) forests in the Pacific Northwest is an area of interest for resource managers. To meet future demands for timber supply as well as provide stands that are visually acceptable by the public and ecologically viable, a thorough understanding of these...

  10. Changes in tracheid and ray traits in fire scars of North American conifers and their ecophysiological implications

    Science.gov (United States)

    Estelle Arbellay; Markus Stoffel; Elaine K. Sutherland; Kevin T. Smith; Donald A. Falk

    2014-01-01

    Fire scars have been widely used as proxies for the reconstruction of fire history; however, little is known about the impact of fire injury on wood anatomy. This study investigates changes in tracheid and ray traits in fire scars of Douglas fir (Pseudotsuga menziesii), western larch (Larix occidentalis) and ponderosa pine (

  11. Fire and mice: Seed predation moderates fire's influence on conifer recruitment

    Science.gov (United States)

    Rafal Zwolak; Dean E. Pearson; Yvette K. Ortega; Elizabeth E. Crone

    2010-01-01

    In fire-adapted ecosystems, fire is presumed to be the dominant ecological force, and little is known about how consumer interactions influence forest regeneration. Here, we investigated seed predation by deer mice (Peromyscus maniculatus) and its effects on recruitment of ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) seedlings in unburned...

  12. Bedrock type significantly affects individual tree mortality for various conifers in the inland Northwest, U.S.A

    Science.gov (United States)

    James A. Moore; David A Hamilton; Yu Xiao; John Byrne

    2004-01-01

    Individual tree mortality models for western white pine (Pinus monticola Dougl. ex D. Don), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), grand fir (Abies grandis (Dougl. ex D. Don) Lindl.), western redcedar (Thuja plicata Donn ex. D. Don), western hemlock (Tsuga heterophylla (Raf.) Sarg.), and western larch (Larix occidentalis Nutt.) were developed using data...

  13. Fuels planning: science synthesis and integration; environmental consequences fact sheet 15: The Wildlife Habitat Response Model

    Science.gov (United States)

    David Pilliod

    2005-01-01

    The Wildlife Habitat Response Model (WHRM) is a Web-based computer tool for evaluating the potential effects of fuel-reduction projects on terrestrial wildlife habitats. It uses species-habitat associations in ponderosa pine (Pinus ponderosa), dry-type Douglas-fir (Pseudotsuga menziesii), lodgepole pine (Pinus...

  14. Evaluation of Methods for Physical Characterization of the Fine Particle Emissions from Two Residential Wood Combustion Appliances

    Science.gov (United States)

    The fine particulate matter (PM) emissions from a U. S. certified non-catalytic wood stove and a zero clearance fireplace burning Quercus rubra L. (northern red oak) and Pseudotsuga menziesii (Douglas fir) cordwood each at two different moisture levels were determined. Emission t...

  15. SPECIES-SPECIFIC PARTITIONING OF SOIL WATER RESOURCES IN AN OLD-GROWTH DOUGLAS-FIR/WESTERN HEMLOCK FOREST

    Science.gov (United States)

    Although tree- and stand-level estimates of forest water use are increasingly common, relatively little is known about partitioning of soil water resources among co-occurring tree species. We studied seasonal courses of soil water utilization in a 450-year-old Pseudotsuga menzies...

  16. Mixed-Species Effects on Soil C and N Stocks, C/N Ratio and pH Using a Transboundary Approach in Adjacent Common Garden Douglas-Fir and Beech Stands

    Directory of Open Access Journals (Sweden)

    Seid Muhie Dawud

    2017-03-01

    Full Text Available Mixed forest of Douglas-fir and beech has been suggested as one of the possible future forest types in Northwest Europe but the effects of this mixed forest on soil properties relative to monoculture stands are unknown. In a transboundary investigation of adjacent common garden Douglas-fir and beech stands, we determined the effects on topsoil properties. However, responses of C and N stocks, the C/N ratio and pH were site- and soil layer-specific and were mainly single-sided and without synergistic effects. Beech reduced the soil C and N stocks in Douglas-fir at the nutrient-poor site, caused an increase in the C/N ratio in the forest floor and mineral soil at both nutrient-poor and -rich sites, and reduced the acidifying effect of Douglas-fir at the nutrient-poor site. These results do not support the hypothesis that mixture effects would be consistent across sites and soil layers. The lack of synergistic effects may be attributed to the relatively similar litter quality or rooting depth that prevented any larger niche differentiation and complementarity. The results indicate that the transboundary approach within a mature common garden proved useful as a platform to test tree species interactions, and this approach could be explored in soil studies until dedicated mixed-species common gardens reach maturity.

  17. A perfect storm: multiple stressors interact to drive postfire regeneration failure of lodgepole pine and Douglas-fir forests in Yellowstone

    Science.gov (United States)

    Hansen, W. D.; Braziunas, K. H.; Rammer, W.; Seidl, R.; Turner, M. G.

    2017-12-01

    Twenty-first century forests will experience increased stress as environmental conditions and disturbance regimes change. Whether forests retain their structure or transitions to alternate states, particularly when affected by multiple stressors, remains unresolved. Subalpine forests in Yellowstone National Park, WY experience large severe wildfires, and postfire-tree regeneration is necessary to assure resilience. Drying is projected, causing frequent larger wildfires that could reduce seed supply and drought that could constrain postfire-seedling establishment. We asked what combinations of warming-drying conditions, increased fire frequency, and increased burned-patch size cause postfire tree-regeneration failure in Yellowstone? We conducted a simulation experiment to identify combinations of fire frequency, fire size, postfire climate, substrate type, and elevation where lodgepole-pine and Douglas-fir regeneration failed. We expected postfire densities to be reduced if burned-patch sizes exceeded effective dispersal distance, sequential fires burned before trees reached reproductive maturity, or drought occurred after fire. We also expected regeneration failure only where multiple stressors occurred simultaneously at low elevation or on poor substrates.Douglas-fir stands were most vulnerable to regeneration failure. 98% of simulated Douglas-fir stands located in the middle of large burned patches failed to regenerate 30 years post fire. Lodgepole-pine stands in the middle of large burned patches failed to regenerate if they were also located at low elevations (93%) or at higher elevations on soils with poor water retention (73%). Stands of serotinous lodgepole (i.e., trees with closed cones that open when heated) also failed to regenerate if fire recurred before trees were reproductively mature (82%). Drought constrained postfire regeneration, yet, enhanced establishment due to release from cold-temperatures during mid-to-late 21st century often outweighed

  18. Impact of Nitrogen Fertilization on Forest Carbon Sequestration and Water Loss in a Chronosequence of Three Douglas-Fir Stands in the Pacific Northwest

    Directory of Open Access Journals (Sweden)

    Xianming Dou

    2015-05-01

    Full Text Available To examine the effect of nitrogen (N fertilization on forest carbon (C sequestration and water loss, we used an artificial neural network model to estimate C fluxes and evapotranspiration (ET in response to N fertilization during four post-fertilization years in a Pacific Northwest chronosequence of three Douglas-fir stands aged 61, 22 and 10 years old in 2010 (DF49, HDF88 and HDF00, respectively. Results showed that N fertilization increased gross primary productivity (GPP for all three sites in all four years with the largest absolute increase at HDF00 followed by HDF88. Ecosystem respiration increased in all four years at HDF00, but decreased over the last three years at HDF88 and over all four years at DF49. As a result, fertilization increased the net ecosystem productivity of all three stands with the largest increase at HDF88, followed by DF49. Fertilization had no discernible effect on ET in any of the stands. Consequently, fertilization increased water use efficiency (WUE in all four post-fertilization years at all three sites and also increased light use efficiency (LUE of all the stands, especially HDF00. Our results suggest that the effects of fertilization on forest C sequestration and water loss may be associated with stand age and fertilization; the two younger stands appeared to be more efficient than the older stand with respect to GPP, WUE and LUE.

  19. Selecting Populations for Non-Analogous Climate Conditions Using Universal Response Functions: The Case of Douglas-Fir in Central Europe.

    Science.gov (United States)

    Chakraborty, Debojyoti; Wang, Tongli; Andre, Konrad; Konnert, Monika; Lexer, Manfred J; Matulla, Christoph; Schueler, Silvio

    2015-01-01

    Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before

  20. Selecting Populations for Non-Analogous Climate Conditions Using Universal Response Functions: The Case of Douglas-Fir in Central Europe

    Science.gov (United States)

    Chakraborty, Debojyoti; Wang, Tongli; Andre, Konrad; Konnert, Monika; Lexer, Manfred J.; Matulla, Christoph; Schueler, Silvio

    2015-01-01

    Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before

  1. Depression of belowground respiration is more pronounced than enhancement of photosynthesis during the first year after nitrogen fertilization of a mature Pacific Northwest Douglas-fir forest

    Science.gov (United States)

    Chen, B.; Black, T. A.; Jassal, R.; Nesic, Z.; Bruemmer, C.

    2008-05-01

    Nitrogen (N) additions to forest have shown variable effects on both respiration and photosynthesis. With increasing rates of anthropogenic N deposition, there is a strong need to understand the ecosystem response to N inputs. We investigated how N fertilization affects the ecosystem carbon (C) balance of a 57-year-old coast Douglas-fir stand in British Columbia, Canada, based on eddy-covariance (EC) and soil-chamber (fertilized and control plots) measurements and process-based modeling. The stand was fertilized by helicopter with urea at 200 kg N ha-1 in January 2007. A land surface model (Ecosystem Atmosphere Simulation Scheme, EASS) was combined with an ecosystem model (Boreal Ecosystem Productivity Simulator, BEPS) and a coupled C and N subroutine was incorporated into the integrated EASS-BEPS model in this study. This half-hourly time step model was run continuously for the period from 2001 to 2007 in two scenarios: with and without fertilization. Modeled C fluxes without fertilization [net ecosystem productivity (NEP), gross primary productivity (GPP), ecosystem respiration (Re) and belowground respiration (Rs)] agreed well with EC and soil chamber measurements over diurnal, seasonal and annual time scales for 2001 to 2006; while simulated NEP, GPP, Re and Rs with fertilization reasonably followed EC and chamber measurements in 2007 (545 vs. 520, 2163 vs. 2155, 1618 vs. 1635, and 920 vs. 906 g C m-2 yr-1, respectively). Comparison of EC-determined C fluxes in 2007 with model simulations without fertilization suggests that annual Re decreased by 6.7% (1635 vs. 1752 g C m-2), gross primary productivity (GPP) increased by 6.8% (2155 vs. 2017 g C m-2), and annual NEP increased by 96.2% (520 vs. 265 g C m-2) due to fertilization. The modeled reduction in Rs (9.6%, comparing modeled values without and with fertilization: 1008 vs. 920 g C m-2 yr-1) is consistent with that measured using the soil chambers (~11.5%, comparing CO2 effluxes from control and fertilized

  2. Soil Greenhouse Gas Fluxes in a Pacific Northwest Douglas-Fir Forest: Results from a Soil Fertilization and Biochar Addition Experiment

    Science.gov (United States)

    Hawthorne, I.; Johnson, M. S.; Jassal, R. S.; Black, T. A.

    2013-12-01

    Rising atmospheric concentrations of greenhouse gases (GHGs), carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), linked to current climate change has stimulated a scientific response to provide robust accounting of sources and sinks of these gases. There is an urgent need to increase awareness of land management impacts on GHG flux dynamics to facilitate the development of management strategies that minimize GHG emissions. Biochar (pyrolyzed organic matter) has been identified as a strategy to reduce net GHG fluxes from soils. This is due to its potential to sequester large amounts of carbon for significant time periods, as well as its modification of biotic and abiotic soil conditions, which in turn can alter the GHG balance. This study describes the effect of biochar and urea-N application on soil surface CO2, CH4 and N2O fluxes in a Pacific Northwest Douglas-fir forest on Vancouver Island, BC, Canada (49o 52' N, 125o 20' W). We used a randomized complete-block design with four replicates of the following treatments: i) control, ii) 5 Mg ha-1 biochar surface application, iii) 200 kg N ha-1 urea pellets surface application, and iv) 5 Mg ha-1 biochar plus 200 kg N ha-1 urea. Soil GHG flux measurements were made biweekly for two years beginning in September 2011 using a non-steady-state non-flow through chamber technique. Biochar was added in February 2012, with urea applied in March 2013. A collar made from 21-cm diameter x 11-cm long PVC piping was installed in each of the 16 plots between two large trees on the forest floor, penetrating the organic layer to the mineral soil at the 5-8 cm depth. A clear Plexiglas lid, equipped with a 10-cm long vent tube and 9-V fan, was placed on each collar when making measurements, with 20-mL samples of chamber headspace air collected at 0, 3, 6, 9 and 12 min using a medical syringe with 21-gauge needle inserted through a rubber septum in the chamber lid. Samples were injected into and transported in previously

  3. Arbutus menziesii Pursh. Pacific madrone

    Science.gov (United States)

    Philip M. McDonald

    1990-01-01

    Pacific madrone (Arbutus menziesii) is one of the most widely distributed tree species native to the Pacific coast. Named for its discoverer, Archibald Menzies, a 19th century Scottish physician and naturalist, the species is called arbutus in Canada, and madrone, madroña, or madroño in the United States. The latter name is...

  4. Effect of thinning, fertilization with biosolids, and weather on interannual ring specific gravity and carbon accumulation of a 55-year-old Douglas-fir stand in western Washington

    Energy Technology Data Exchange (ETDEWEB)

    Kantavichai, R.; Briggs, D.G.; Turnblom, E.C. [Washington Univ., Seattle, WA (United States). School of Forest Resources

    2010-01-15

    Soil moisture deficits (SMD) cause trees to conserve water by closing stomata, which in turn limits the uptake of atmospheric carbon dioxide (CO{sub 2}) and curtails photosynthesis and wood formation. This study investigated the combined effect of temperature, precipitation, SMD, and various silviculture treatments on interannual ring specific gravity (SG). A model was developed to predict post-treatment interannual ring SG from the treatment and environmental variables. The study assumed that thinning the stand would increase SG, while fertilization with biosolids would decrease SG. The SGs associated with each treatment were then used to calculate the dry mass and carbon content associated with stem growth. Results were then compared with estimates taken from standard publications. The experiment was conducted on a 55-year old Douglas fir stand. Twelve rings were used to assess the effect of the treatments. The study showed that use of the published average to consider only carbon sequestered by tree growth distorts the comparison of management regimes. The thinning process produced logs from which long-term structures were built, and continue to sequester carbon. When product pools of stored carbon are combined with forest carbon pools, thinning and biosolids treatment regimes are preferable to other carbon storage regimes. 40 refs., 6 tabs., 2 figs.

  5. Examining Pseudotsuga menziesii biomass change dynamics through succession using a regional forest inventory system

    Science.gov (United States)

    David M. Bell; Andrew N. Gray

    2015-01-01

    Models of forest succession provide an appealing conceptual framework for understanding forest dynamics, but uncertainty in the degree to which patterns are regionally consistent might limit the application of successional theory in forest management. Remeasurements of forest inventory networks provide an opportunity to assess this consistency, improving our...

  6. Structure and Composition of a Dry Mixed-Conifer Forest in Absence of Contemporary Treatments, Southwest, USA

    Directory of Open Access Journals (Sweden)

    Douglas Cram

    2017-09-01

    Full Text Available Dry mixed-conifer forests in the Southwest occupy an important ecological and hydrological role in upper watersheds. In the absence of reoccurring fire and silvicultural treatments over the last 50 years, we quantified forest structure and composition on prevailing north and south aspects of a dry mixed-conifer forest in southcentral New Mexico using mixed models and ordination analysis in preparation for an experiment in ecological restoration. Results indicated overstory and midstory were dominated by Douglas-fir (Pseudotsuga menziesii and shade tolerant/fire intolerant white fir (Abies concolor with interspersed mature aspen on north aspects, and Douglas-fir and Southwestern white pine (Pinus strobiformis on south aspects. Ponderosa pine (Pinus ponderosa, which was historically co-dominant with Douglas-fir on north and south aspects, was subdominant on south aspects and almost entirely absent on north aspects. Regeneration was dominated by white fir saplings and seedlings on north aspects while ponderosa pine was completely absent. South aspect saplings and seedlings were characterized by Douglas-fir and Southwestern white pine, but almost no ponderosa pine. Ordination analysis characterized the effect of aspect on species composition. Understanding contemporary forest structure and composition is important when planning for desired future conditions that are to be achieved through ecological restoration using silvicultural techniques designed to foster resilience.

  7. Observations of the scale-dependent turbulence and evaluation of the flux–gradient relationship for sensible heat for a closed Douglas-fir canopy in very weak wind conditions

    Directory of Open Access Journals (Sweden)

    D. Vickers

    2014-09-01

    Full Text Available Observations of the scale-dependent turbulent fluxes, variances, and the bulk transfer parameterization for sensible heat above, within, and beneath a tall closed Douglas-fir canopy in very weak winds are examined. The daytime sub-canopy vertical velocity spectra exhibit a double-peak structure with peaks at timescales of 0.8 s and 51.2 s. A double-peak structure is also observed in the daytime sub-canopy heat flux co-spectra. The daytime momentum flux co-spectra in the upper bole space and in the sub-canopy are characterized by a relatively large cross-wind component, likely due to the extremely light and variable winds, such that the definition of a mean wind direction, and subsequent partitioning of the momentum flux into along- and cross-wind components, has little physical meaning. Positive values of both momentum flux components in the sub-canopy contribute to upward transfer of momentum, consistent with the observed sub-canopy secondary wind speed maximum. For the smallest resolved scales in the canopy at nighttime, we find increasing vertical velocity variance with decreasing timescale, consistent with very small eddies possibly generated by wake shedding from the canopy elements that transport momentum, but not heat. Unusually large values of the velocity aspect ratio within the canopy were observed, consistent with enhanced suppression of the horizontal wind components compared to the vertical by the very dense canopy. The flux–gradient approach for sensible heat flux is found to be valid for the sub-canopy and above-canopy layers when considered separately in spite of the very small fluxes on the order of a few W m−2 in the sub-canopy. However, single-source approaches that ignore the canopy fail because they make the heat flux appear to be counter-gradient when in fact it is aligned with the local temperature gradient in both the sub-canopy and above-canopy layers. While sub-canopy Stanton numbers agreed well with values

  8. Carbon Transfers and Emissions Following Harvest and Pile Burning in Coastal Douglas-fir Forests Determined from Analysis of High-Resolution UAV Imagery and Point Clouds and from Field Surveys.

    Science.gov (United States)

    Trofymow, J. A.; Gougeon, F.; Kelley, J. W.

    2017-12-01

    Forest carbon (C) models require knowledge on C transfers due to intense disturbances such as fire, harvest, and slash burning. In such events, live trees die and C transferred to detritus or exported as round wood. With burning, live and detrital C is lost as emissions. Burning can be incomplete, leaving wood, charred and scattered or in unburnt rings and piles. For harvests, all round wood volume is routinely measured, while dispersed and piled residue volumes are typically assessed in field surveys, scaled to a block. Recently, geospatial methods have been used to determine, for an entire block, piled residues using LiDAR or image point clouds (PC) and dispersed residues by analysis of high-resolution imagery. Second-growth Douglas-fir forests on eastern Vancouver Island were examined, 4 blocks at Oyster River (OR) and 2 at Northwest Bay (NB). OR blocks were cut winter 2011, piled spring 2011, field survey, aerial RGB imagery and LiDAR PC acquired fall 2011, piles burned, burn residues surveyed, and post-burn aerial RGB imagery acquired 2012. NB blocks were cut fall 2014, piled spring 2015, field survey, UAV RGB imagery and image PC acquired summer 2015, piles burned and burn residues surveyed spring 2016, and post-burn UAV RGB imagery and PC acquired fall 2016. Volume to biomass conversion used survey species proportions and wood density. At OR, round wood was 261.7 SE 13.1, firewood 1.7 SE 0.3, and dispersed residue by survey, 13.8 SE 3.6 tonnes dry mass (t dm) ha-1. Piled residues were 8.2 SE 0.9 from pile surveys vs. 25.0 SE 5.9 t dm ha-1 from LiDAR PC bulk pile volumes and packing ratios. Post-burn, piles lost 5.8 SE 0.5 from survey of burn residues vs. 18.2 SE 4.7 t dm ha-1 from pile volume changes using 2011 LiDAR PC and 2012 imagery. The percentage of initial merchantable biomass exported as round & fire wood, remaining as dispersed & piled residue, and lost to burning was, respectively, 92.5%, 5.5% and 2% using only field methods vs. 87%, 7% and 6% from

  9. Changes to the N cycle following bark beetle outbreaks in two contrasting conifer forest types.

    Science.gov (United States)

    Griffin, Jacob M; Turner, Monica G

    2012-10-01

    Outbreaks of Dendroctonus beetles are causing extensive mortality in conifer forests throughout North America. However, nitrogen (N) cycling impacts among forest types are not well known. We quantified beetle-induced changes in forest structure, soil temperature, and N cycling in Douglas-fir (Pseudotsuga menziesii) forests of Greater Yellowstone (WY, USA), and compared them to published lodgepole pine (Pinus contorta var. latifolia) data. Five undisturbed stands were compared to five beetle-killed stands (4-5 years post-outbreak). We hypothesized greater N cycling responses in Douglas-fir due to higher overall N stocks. Undisturbed Douglas-fir stands had greater litter N pools, soil N, and net N mineralization than lodgepole pine. Several responses to disturbance were similar between forest types, including a pulse of N-enriched litter, doubling of soil N availability, 30-50 % increase in understory cover, and 20 % increase in foliar N concentration of unattacked trees. However, the response of some ecosystem properties notably varied by host forest type. Soil temperature was unaffected in Douglas-fir, but lowered in lodgepole pine. Fresh foliar %N was uncorrelated with net N mineralization in Douglas-fir, but positively correlated in lodgepole pine. Though soil ammonium and nitrate, net N mineralization, and net nitrification all doubled, they remained low in both forest types (mineralization; litter and soil N cycling similarly in each forest type, despite substantial differences in pre-disturbance biogeochemistry. In contrast, soil temperature and soil N-foliar N linkages differed between host forest types. This result suggests that disturbance type may be a better predictor of litter and soil N responses than forest type due to similar disturbance mechanisms and disturbance legacies across both host-beetle systems.

  10. Nitrogen Fertilization Effects on Net Ecosystem and Net Primary Productivities as Determined from Flux Tower, Biometric, and Model Estimates for a Coastal Douglas-fir Forest in British Columbia

    Science.gov (United States)

    Trofymow, J. A.; Metsaranta, J. M.; Black, T. A.; Jassal, R. S.; Filipescu, C.

    2013-12-01

    In coastal BC, 6,000-10,000 ha of public and significant areas of private forest land are annually fertilized with nitrogen, with or without thinning, to increase merchantable wood and reduce rotation age. Fertilization has also been viewed as a way to increase carbon (C) sequestration in forests and obtain C offsets. Such offset projects must demonstrate additionality with reference to a baseline and include monitoring to verify net C gains over the project period. Models in combination with field-plot measurements are currently the accepted methods for most C offset protocols. On eastern Vancouver Island, measurements of net ecosystem production (NEP), ecosystem respiration (Re) and gross primary productivity (GPP) using the eddy-covariance (EC) technique as well as component C fluxes and stocks have been made since 1998 in an intermediate-aged Douglas-fir dominated forest planted in 1949. In January 2007 an area around the EC flux tower was aerially fertilized with 200 kg urea-N ha-1. Ground plots in the fertilized area and an adjacent unfertilized control area were also monitored for soil (Rs) and heterotrophic (Rh) respiration, litterfall, and tree growth. To determine fertilization effects on whole tree growth, sample trees were felled in both areas for the 4-year (2003-06) pre- and the 4-year (2007-10) post-fertilization periods and were compared with EC NEP estimates and tree-ring based NEP estimates from Carbon Budget Model - Canadian Forest Sector (CBM-CFS3) for the same periods. Empirical equations using climate and C fluxes from 1998-2006 were derived to estimate what the EC fluxes would have been in 2007-10 for the fertilized area had it been unfertilized. Mean EC NEP for 2007-10 was 561 g C m2 y-1 , a 64% increase above pre-fertilization NEP (341 g C m2 y-1) or 28% increase above estimated unfertilized NEP (438 g C m2 y-1). Most of the increase was attributed to increased tree C uptake (i.e., GPP), with little change in Re. In 2007 fertilization

  11. Tree species and soil nutrient profiles in old-growth forests of the Oregon Coast Range

    Science.gov (United States)

    Cross, Alison; Perakis, Steven S.

    2011-01-01

    Old-growth forests of the Pacific Northwest provide a unique opportunity to examine tree species – soil relationships in ecosystems that have developed without significant human disturbance. We characterized foliage, forest floor, and mineral soil nutrients associated with four canopy tree species (Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco), western hemlock (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Thuja plicata Donn ex D. Don), and bigleaf maple (Acer macrophyllum Pursh)) in eight old-growth forests of the Oregon Coast Range. The greatest forest floor accumulations of C, N, P, Ca, Mg, and K occurred under Douglas-fir, primarily due to greater forest floor mass. In mineral soil, western hemlock exhibited significantly lower Ca concentration and sum of cations (Ca + Mg + K) than bigleaf maple, with intermediate values for Douglas-fir and western redcedar. Bigleaf maple explained most species-based differences in foliar nutrients, displaying high concentrations of N, P, Ca, Mg, and K. Foliar P and N:P variations largely reflected soil P variation across sites. The four tree species that we examined exhibited a number of individualistic effects on soil nutrient levels that contribute to biogeochemical heterogeneity in these ecosystems. Where fire suppression and long-term succession favor dominance by highly shade-tolerant western hemlock, our results suggest a potential for declines in both soil Ca availability and soil biogeochemical heterogeneity in old-growth forests.

  12. Laser incising of wood: Impregnation of columns with water-soluble dye

    International Nuclear Information System (INIS)

    Hattori, N.; Ando, K.; Kitayama, S.; Nakamura, Y.

    1994-01-01

    To know whether or not laser incising is a useful pre-treatment technique in impregnating a chemical fluid into lumber, pin holes were made in columns of hinoki (Chamaecyparis obtusa Endl.), sugi (Cryptomeria japonica D. Don), karamatsu (Larix leptolepis Gordon) and douglas-fir (Pseudo-tsuga menziesii Franco) with 1.7 kW CO2 laser, and a water-soluble dye was impregnated into these columns with a local pressure impregnation device. Retentions, and lengths and widths of penetrations from each hole were measured quantitatively. Referring to the results of the preparatory experiment mentioned above, incising patterns for sugi and douglas-fir were designed, and the same water-soluble dye was impregnated into the laser-incised columns as well as into non-incised ones with the vacuum-pressure method to obtain penetrated layers with the target depths completely. As a result, a retention of 200 kg/m3 of dye could be achieved for a column of douglas-fir even if it is a species difficult to impregnate. The penetrated layer also could be formed completely at the depth of the laser incision. Therefore, it is concluded that laser incising can be used for the pre-treatment before impregnation of wood columns. (author)

  13. Antimicrobial activity of some Pacific Northwest woods against anaerobic bacteria and yeast.

    Science.gov (United States)

    Johnston, W H; Karchesy, J J; Constantine, G H; Craig, A M

    2001-11-01

    Extracts of woods commonly used for animal bedding were tested for antimicrobial activity. Essential oils from Alaska cedar (Chamaecyparis nootkatensis), western juniper (Juniperus occidentalis) and old growth Douglas fir (Pseudotsuga menziesii) as well as methanol extracts of wood from these trees plus western red cedar (Thuja plicata) and ponderosa pine (Pinus ponderosa) were tested for antimicrobial activity against anaerobic bacteria and yeast. The test microbes included Fusobacterium necrophorum, Clostridium perfringens, Actinomyces bovis and Candida albicans which are common to foot diseases and other infections in animals. The essential oils and methanol extracts were tested using a standardized broth assay. Only extracts of Alaska cedar and western juniper showed significant antimicrobial activity against each of the microbes tested. The essential oil of Douglas fir did show antimicrobial activity against A. bovis at the concentrations tested. The methanol extracts of the heartwood of Douglas fir and the sapwood of ponderosa pine showed no antimicrobial activity. The major chemical components of western juniper (cedrol and alpha- and beta-cedrene) and Alaska cedar (nootkatin) were also tested. In western juniper, alpha- and beta-cedrene were found to be active components. Nootkatin showed activity only against C. albicans. The inhibitory activity in Alaska cedar oil was high enough to justify further efforts to define the other chemical components responsible for the antimicrobial activity. Copyright 2001 John Wiley & Sons, Ltd.

  14. Spatially nonrandom tree mortality and ingrowth maintain equilibrium pattern in an old-growth Pseudotsuga-Tsuga forest.

    Science.gov (United States)

    Lutz, James A; Larson, Andrew J; Furniss, Tucker J; Donato, Daniel C; Freund, James A; Swanson, Mark E; Bible, Kenneth J; Chen, Jiquan; Franklin, Jerry F

    2014-08-01

    Mortality processes in old-growth forests are generally assumed to be driven by gap-scale disturbance, with only a limited role ascribed to density-dependent mortality, but these assumptions are rarely tested with data sets incorporating repeated measurements. Using a 12-ha spatially explicit plot censused 13 years apart in an approximately 500-year-old Pseudotsuga-Tsuga forest, we demonstrate significant density-dependent mortality and spatially aggregated tree recruitment. However, the combined effect of these strongly nonrandom demographic processes was to maintain tree patterns in a state of dynamic equilibrium. Density-dependent mortality was most pronounced for the dominant late-successional species, Tsuga heterophylla. The long-lived, early-seral Pseudotsuga menziesii experienced an annual stem mortality rate of 0.84% and no new recruitment. Late-seral species Tsuga and Abies amabilis had nearly balanced demographic rates of ingrowth and mortality. The 2.34% mortality rate for Taxus brevifolia was higher than expected, notably less than ingrowth, and strongly affected by proximity to Tsuga. Large-diameter Tsuga structured both the regenerating conspecific and heterospecific cohorts with recruitment of Tsuga and Abies unlikely in neighborhoods crowded with large-diameter competitors (P old-growth forests.

  15. Freezing tolerance of conifer seeds and germinants.

    Science.gov (United States)

    Hawkins, B J; Guest, H J; Kolotelo, D

    2003-12-01

    Survival after freezing was measured for seeds and germinants of four seedlots each of interior spruce (Picea glauca x engelmannii complex), lodgepole pine (Pinus contorta Dougl. ex Loud.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western red cedar (Thuja plicata Donn ex D. Donn). Effects of eight seed treatments on post-freezing survival of seeds and germinants were tested: dry, imbibed and stratified seed, and seed placed in a growth chamber for 2, 5, 10, 15, 20 or 30 days in a 16-h photoperiod and a 22/17 degrees C thermoperiod. Survival was related to the water content of seeds and germinants, germination rate and seedlot origin. After freezing for 3 h at -196 degrees C, dry seed of most seedlots of interior spruce, Douglas-fir and western red cedar had 84-96% germination, whereas lodgepole pine seedlots had 53-82% germination. Freezing tolerance declined significantly after imbibition in lodgepole pine, Douglas-fir and interior spruce seed (western red cedar was not tested), and mean LT50 of imbibed seed of these species was -30, -24.5 and -20 degrees C, respectively. Freezing tolerance continued to decline to a minimum LT50 of -4 to -7 degrees C after 10 days in a growth chamber for interior spruce, Douglas-fir and lodgepole pine, or after 15 days for western red cedar. Minimum freezing tolerance was reached at the stage of rapid hypocotyl elongation. In all species, a slight increase in freezing tolerance of germinants was observed once cotyledons emerged from the seed coat. The decrease in freezing tolerance during the transition from dry to germinating seed correlated with increases in seed water content. Changes in freezing tolerance between 10 and 30 days in the growth chamber were not correlated with seedling water content. Within a species, seedlots differed significantly in freezing tolerance after 2 or 5 days in the growth chamber. Because all seedlots of interior spruce and lodgepole pine germinated quickly, there was no correlation

  16. Bijdrage tot de kennis van den groei van Pseudotsuga taxifolia Britton in Nederland in verband met zijn beteekenis voor den Nederlandschen boschbouw

    NARCIS (Netherlands)

    Hoogh, de J.

    1925-01-01

    Development of the green Douglas fir in the Netherlands in different places with different methods of planting was studied by enquiry, personal research and from the literature. The climate and soil types seemed suitable. Game, insects and fungi caused little damage. The stands studied all derived

  17. 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.

  18. Biogeochemical prospecting for uranium with conifers: results from the Midnite mine area, Washington

    International Nuclear Information System (INIS)

    Nash, J.T.; Ward, F.N.

    1977-01-01

    The ash of needles, cones, and duff from Ponderosa pine (Pinus ponderosa Laws) growing near uranium deposits of the Midnite mine, Stevens County, Wash., contain as much as 200 ppM uranium. Needle samples containing more than 10 ppM uranium define zones that correlate well with known uranium deposits or dumps. Dispersion is as much as 300 m but generally is less. Background is about 1 ppM. Tree roots are judged to be sampling ore, low-grade uranium halo, or ground water to a depth of about 15 m. Uptake of uranium by Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) needles appears to be about the same as by Ponderosa pine needles. Cones and duff are generally enriched in uranium relative to needles. Needles, cones, and duff are recommended as easily collected, uncomplicated sample media for geochemical surveys. Samples can be analyzed by standard methods and total cost per sample kept to about $6

  19. Mycorrhiza reduces adverse effects of dark septate endophytes (DSE) on growth of conifers.

    Science.gov (United States)

    Reininger, Vanessa; Sieber, Thomas N

    2012-01-01

    Mycorrhizal roots are frequently colonized by fungi of the Phialocephala fortinii s.l.-Acephala applanata species complex (PAC). These ascomycetes are common and widespread colonizers of tree roots. Some PAC strains reduce growth increments of their hosts but are beneficial in protecting roots against pathogens. Nothing is known about the effects of PAC on mycorrhizal fungi and the PAC-mycorrhiza association on plant growth, even though these two fungal groups occur closely together in natural habitats. We expect reduced colonization rates and reduced negative effects of PAC on host plants if roots are co-colonized by an ectomycorrhizal fungus (ECM). Depending on the temperature regime interactions among the partners in this tripartite ECM-PAC-plant system might also change. To test our hypotheses, effects of four PAC genotypes (two pathogenic and two non-pathogenic on the Norway spruce), mycorrhization by Laccaria bicolor (strain S238N) and two temperature regimes (19°C and 25°C) on the biomass of the Douglas-fir (Pseudotsuga menziesii) and Norway spruce (Picea abies) seedlings were studied. Mycorrhization compensated the adverse effects of PAC on the growth of the Norway spruce at both temperatures. The growth of the Douglas-fir was not influenced either by PAC or mycorrhization at 19°C, but at 25°C mycorrhization had a similar protective effect as in the Norway spruce. The compensatory effects probably rely on the reduction of the PAC-colonization density by mycorrhizae. Temperature and the PAC strain only had a differential effect on the biomass of the Norway spruce but not on the Douglas-fir. Higher temperature reduced mycorrhization of both hosts. We conclude that ectomycorrhizae form physical and/or physiological barriers against PAC leading to reduced PAC-colonization of the roots. Additionally, our results indicate that global warming could cause a general decrease of mycorrhization making primary roots more accessible to other symbionts and pathogens.

  20. Thinning, tree-growth, and resistance to multi-year drought in a mixed-conifer forest of northern California

    Science.gov (United States)

    Vernon, Michael J.; Sherriff, Rosemary L.; van Mantgem, Phillip; Kane, Jeffrey M.

    2018-01-01

    Drought is an important stressor in forest ecosystems that can influence tree vigor and survival. In the U.S., forest managers use two primary management techniques to promote resistance and resilience to drought: prescribed fire and mechanical thinning. Generally applied to reduce fuels and fire hazard, treatments may also reduce competition for resources that may improve tree-growth and reduce mortality during drought. A recent severe and prolonged drought in California provided a natural experiment to investigate tree-growth responses to fuel treatments and climatic stress. We assessed tree-growth from 299 ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) in treated and untreated stands during severe drought from 2012 to 2015 in the mixed-conifer forests of Whiskeytown National Recreation Area (WNRA) in northern California. The treatment implemented at WNRA removed 34% of live basal area through mechanical thinning with a subsequent pile burning of residual fuels. Tree-growth was positively associated with crown ratio and negatively associated with competition and a 1-year lag of climate water deficit, an index of drought. Douglas-fir generally had higher annual growth than ponderosa pine, although factors affecting growth were the same for both species. Drought resistance, expressed as the ratio between mean growth during drought and mean growth pre-drought, was higher in treated stands compared to untreated stands during both years of severe drought (2014 and 2015) for ponderosa pine but only one year (2014) for Douglas-fir. Thinning improved drought resistance, but tree size, competition and species influenced this response. On-going thinning treatments focused on fuels and fire hazard reduction are likely to be effective at promoting growth and greater drought resistance in dry mixed-conifer forests. Given the likelihood of future droughts, land managers may choose to implement similar treatments to reduce potential impacts.

  1. Analysis of enantiomeric and non-enantiomeric monoterpenes in plant emissions using portable dynamic air sampling/solid-phase microextraction (PDAS-SPME) and chiral gas chromatography/mass spectrometry

    Science.gov (United States)

    Yassaa, Noureddine; Williams, Jonathan

    A portable dynamic air sampler (PDAS) using a porous polymer solid-phase microextraction (SPME) fibre has been validated for the determination of biogenic enantiomeric and non-enantiomeric monoterpenes in air. These compounds were adsorbed in the field, and then thermally desorbed at 250 °C in a gas chromatograph injector port connected via a β-cyclodextrin capillary separating column to a mass spectrometer. The optimized method has been applied for investigating the emissions of enantiomeric monoterpenes from Pseudotsuga menziesii (Douglas-fir), Rosmarinus officinalis (Rosemary) and Lavandula lanata (Lavender) which were selected as representative of coniferous trees and aromatic plants, respectively. The enantiomers of α-pinene, sabinene, camphene, δ-3-carene, β-pinene, limonene, β-phellandrene, 4-carene and camphor were successfully determined in the emissions from the three plants. While Douglas-fir showed a strong predominance toward (-)-enantiomers, Rosemary and Lavender demonstrated a large variation in enantiomeric distribution of monoterpenes. The simplicity, rapidity and sensitivity of dynamic sampling with porous polymer coated SPME fibres coupled to chiral capillary gas chromatography/mass spectrometry (GC/MS) makes this method potentially useful for in-field investigations of atmosphere-biosphere interactions and studies of optically explicit atmospheric chemistry.

  2. A comparative toxicity assessment of materials used in aquatic construction.

    Science.gov (United States)

    Lalonde, Benoit A; Ernst, William; Julien, Gary; Jackman, Paula; Doe, Ken; Schaefer, Rebecca

    2011-10-01

    Comparative toxicity testing was performed on selected materials that may be used in aquatic construction projects. The tests were conducted on the following materials: (1) untreated wood species (hemlock [Tsuga ssp], Western red cedar (Thuja plicata), red oak [Quercus rubra], Douglas fir [Pseudotsuga menziesii], red pine [Pinus resinosa], and tamarack [Larix ssp]); (2) plastic wood; (3) Ecothermo wood hemlock stakes treated with preservatives (e.g., chromated copper arsenate [CCA], creosote, alkaline copper quaternary [ACQ], zinc naphthenate, copper naphthenate, and Lifetime Wood Treatment); (4) epoxy-coated steel; (5) hot-rolled steel; (6) zinc-coated steel; and (7) concrete. Those materials were used in acute lethality tests with rainbow trout, Daphnia magna, Vibrio fischeri and threespine stickleback. The results indicated the following general ranking of the materials (from the lowest to highest LC(50) values); ACQ > creosote > zinc naphthenate > copper naphthenate > CCA (treated at 22.4 kg/m(3)) > concrete > red pine > western red cedar > red oak > zinc-coated steel > epoxy-coated steel > CCA (6.4 kg/m(3)). Furthermore, the toxicity results indicated that plastic wood, certain untreated wood species (hemlock, tamarack, Douglas fir, and red oak), hot-rolled steel, Ecothermo wood, and wood treated with Lifetime Wood Treatment were generally nontoxic to the test species. © Springer Science+Business Media, LLC 2011

  3. Increment and mortality in a virgin Douglas-fir forest.

    Science.gov (United States)

    Robert W. Steele; Norman P. Worthington

    1955-01-01

    Is there any basis to the forester's rule of thumb that virgin forests eventually reach an equilibrium where increment and mortality approximately balance? Are we wasting potential timber volume by failing to salvage mortality in old-growth stands?

  4. Mineral cycling in a young Douglas fir forest stand

    International Nuclear Information System (INIS)

    Riekerk, H.

    1978-01-01

    Radiotracers for phosphorus ( 32 P), potassium (substitute 86 Rb), and calcium ( 45 Ca) were used to follow the turnover of nutrients entering the forest floor with rainwash. Phosphorus moved readily through the forest floor to be strongly retained by the acid mineral soil. Considerable phosphorus absorbed by trees was correlated with forest-floor leachate contents and became concentrated in physiologically active tissues. Losses with litterfall and rainwash were nondetectable; this indicated high retention and internal redistribution. Rapid movement toward sinks appeared to be characteristic. In contrast, the larger amounts of calcium added were absorbed by the exchange capacity of the forest floor, with subsequent small but relatively unrestricted movement through the soil and trees. Both calcium and potassium absorption by trees was correlated with mineral-soil leachate contents. Annual potassium mobility fell between that of phosphorus and calcium and appeared to be more dependent on temperature and moisture conditions of the forest ecosystem, with potassium moving rapidly in subcycles during wet periods of the growing season

  5. Stress wave nondestructive evaluation of Douglas-fir peeler cores

    Science.gov (United States)

    Robert J. Ross; John I. Zerbe; Xiping Wang; David W. Green; Roy F. Pellerin

    2005-01-01

    With the need for evaluating the utilization of veneer peeler log cores in higher value products and the increasing importance of utilizing round timbers in poles, posts, stakes, and building construction components, we conducted a cooperative project to verify the suitability of stress wave nondestructive evaluation techniques for assessing peeler cores and some...

  6. Interactions between leaf nitrogen status and longevity in relation to N cycling in three contrasting European forest canopies

    Directory of Open Access Journals (Sweden)

    L. Wang

    2013-02-01

    Full Text Available Seasonal and spatial variations in foliar nitrogen (N parameters were investigated in three European forests with different tree species, viz. beech (Fagus sylvatica L., Douglas fir (Pseudotsuga menziesii (Mirb. Franco and Scots pine (Pinus sylvestris L. growing in Denmark, the Netherlands and Finland, respectively. The objectives were to investigate the distribution of N pools within the canopies of the different forests and to relate this distribution to factors and plant strategies controlling leaf development throughout the seasonal course of a vegetation period. Leaf N pools generally showed much higher seasonal and vertical variability in beech than in the coniferous canopies. However, also the two coniferous tree species behaved very differently with respect to peak summer canopy N content and N re-translocation efficiency, showing that generalisations on tree internal vs. ecosystem internal N cycling cannot be made on the basis of the leaf duration alone. During phases of intensive N turnover in spring and autumn, the NH4+ concentration in beech leaves rose considerably, while fully developed green beech leaves had relatively low tissue NH4+, similar to the steadily low levels in Douglas fir and, particularly, in Scots pine. The ratio between bulk foliar concentrations of NH4+ and H+, which is an indicator of the NH3 emission potential, reflected differences in foliage N concentration, with beech having the highest values followed by Douglas fir and Scots pine. Irrespectively of the leaf habit, i.e. deciduous versus evergreen, the majority of the canopy foliage N was retained within the trees. This was accomplished through an effective N re-translocation (beech, higher foliage longevity (fir or both (boreal pine forest. In combination with data from a literature review, a general relationship of decreasing N re

  7. Tree-growth analyses to estimate tree species' drought tolerance.

    Science.gov (United States)

    Eilmann, Britta; Rigling, Andreas

    2012-02-01

    Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree species' potential for surviving future aggravated environmental conditions is rather demanding. The aim of this study was to find a tree-ring-based method suitable for identifying very drought-tolerant species, particularly potential substitute species for Scots pine (Pinus sylvestris L.) in Valais. In this inner-Alpine valley, Scots pine used to be the dominating species for dry forests, but today it suffers from high drought-induced mortality. We investigate the growth response of two native tree species, Scots pine and European larch (Larix decidua Mill.), and two non-native species, black pine (Pinus nigra Arnold) and Douglas fir (Pseudotsuga menziesii Mirb. var. menziesii), to drought. This involved analysing how the radial increment of these species responded to increasing water shortage (abandonment of irrigation) and to increasingly frequent drought years. Black pine and Douglas fir are able to cope with drought better than Scots pine and larch, as they show relatively high radial growth even after irrigation has been stopped and a plastic growth response to drought years. European larch does not seem to be able to cope with these dry conditions as it lacks the ability to recover from drought years. The analysis of trees' short-term response to extreme climate events seems to be the most promising and suitable method for detecting how tolerant a tree species is towards drought. However, combining all the methods used in this study provides a complete picture of how water shortage could limit species.

  8. Four centuries of reconstructed hydroclimatic variability for Northwestern Chihuahua, Mexico, based on tree rings

    Directory of Open Access Journals (Sweden)

    José Villanueva Díaz

    2015-03-01

    Full Text Available A Douglas-fir chronology with a length of 409 years (1600-2008 was developed for northwestern Chihuahua in Mesa de las Guacamayas, a “Natural Protected Area” known as an important nesting habitat for the thickbilled parrot (Rhynchopsitta pachyrhyncha an endangered neotropical bird. Increment cores and cross-sections from selected Douglas-fir trees (Pseudotsuga menziesii in a mixed conifer forest were obtained with an increment borer and a chain-saw. Standard dendrochronological techniques were used to process and date each one of the rings to their exact year of formation. The quality of dating of the measured series was analyzed with the COFECHA program, while biological trends not related to climate (age differences, stem-size increases, and disturbances were removed by standardization procedures in the ARSTAN program. Tree ring series of earlywood, latewood and total ring width were developed for the last four centuries. The total ring-width chronology was significantly associated (r>0.40, p=0.000 with nearby chronologies, particularly those located <200 km apart along the western slopes of the Sierra Madre Occidental (SMO observing correlations as high as 0.69 (p<0.001. Association between chronologies decreased for those sites in the state of Durango along the SMO but separated more than 200 km in straight line and also for sites in nearby borderline in the USA side. The similar climatic response among distant chronologies implies the influence of common atmospheric circulatory patterns affecting a large portion of land simultaneously. ENSO is one of the most important factors in determining inter-annual and multiannual hydroclimatic variability in northern Mexico, increasing winter-spring precipitation in its warm phase and causing extreme droughts in its cold phase.

  9. Ground cover influence on evaporation and stable water isotopes in soil water

    Science.gov (United States)

    Magdalena Warter, Maria; Jiménez-Rodríguez, Cesar D.; Coenders-Gerrits, Miriam; Teuling, Adriaan J. Ryan

    2017-04-01

    Forest ecosystems are characterized by complex structures which influence hydrological processes such as evaporation. The vertical stratification of the forest modifies the effect of the evaporation process due to the composition and local distribution of species within the forest. The evaluation of it will improve the understanding of evaporation in forest ecosystems. To determine the influence of forest understory on the fractionation front, four ground cover types were selected from the Speulderbos forest in the Netherlands. The native species of Thamariskmoss (Thuidium thamariscinum), Rough Stalked Feathermoss (Brachythecium rutabulum), and Haircapmoss (Polytrichum commune) as well as one type of litter made up of Douglas-Fir needles (Pseudotsuga menziesii) were used to analyse the rate of evaporation and changes on the isotopic concentration of the soil water on an in-situ basis in a controlled environment. Over a period of 4 weeks soil water content and atmospheric conditions were continuously measured, while the rainfall simulations were performed with different amounts and timings. The reference water added to the boxes keeps a stable composition along the trial period with a δ ^2H value of -42.59±1.15 \\permil} and δ 18O of -6.01±0.21 \\permil}. The evaporation front in the four ground covers is located between 5 and 10 cm depth and deuterium excess values are bigger than 5 \\permil. The litter layer of Douglas-Fir needles is the cover with higher fractionation in respect to the added water at 10 cm depth (δ ^2H: -29.79 \\permil), while the Haircapmoss keeps the lower fractionation rate at 5 cm and 10 cm (δ ^2H: -33.62 and δ ^2H: -35.34 \\permil). The differences showed by the soil water beneath the different ground covers depict the influence of ground cover on fractionation rates of the soil water, underlining the importance of the spatial heterogeneity of the evaporation front in the first 15 cm of soil.

  10. Estimation the remaining service-lifetime of wooden structure of geothermal cooling tower

    Directory of Open Access Journals (Sweden)

    Effendi Tri Bahtiar

    2017-06-01

    Full Text Available Similar with other construction materials, wood strength is decreasing when applied by long term loading. Wooden cooling tower structure at Star Energy Geothermal (Wayang Windu Ltd was built in 1998 and it should be evaluated to avoid sudden structural failure. Evaluation conducted through several steps: wood species identification, the physical and mechanical properties testing, and estimation for remaining service-lifetime by generating mathematical models derived from creep test and reduction of cross sectional area of the wood. Identification result that the wood are redwood (Sequoia sempervirens and Douglas fir (Pseudotsuga menziesii. The wood density value has degraded from the surface until 0.25 cm depth. Strength characteristics of the wood have considerably decreased, but the allowable stress for bending, tension parallel to grain, and shear were still higher than NDS2005 requirements. The allowable stress for compression parallel to grain was slightly lower than NDS, while compression perpendicular to grain was much lower. Average modulus of elasticity reduces become lower than the value stated by the code, but the minimum value of modulus of elasticity (Emin of redwood was still higher than the code value, while Emin of Douglas fir is slightly lower. Then, in accordance with those findings, the construction would not failure yet but the deformation and vibration will occur in higher rate than design planning. This research develops mathematical models for estimating the remaining service-lifetime of the wooden cooling tower structure in geothermal power plant based on the wood performance in resisting long term loading and its deterioration rate. The deterioration rate of wood member of cooling tower structure at Star Energy Geothermal (Wayang Windu Ltd is 0.0147 cm depth per year, so equation for the residual service life estimation is σlaterσtoday=bh2(b−0.0147T(h−0.0147T2, and σlater must be lower than allowable stress.

  11. Defining historical baselines for conservation: ecological changes since European settlement on Vancouver Island, Canada.

    Science.gov (United States)

    Bjorkman, Anne D; Vellend, Mark

    2010-12-01

    Conservation and restoration goals are often defined by historical baseline conditions that occurred prior to a particular period of human disturbance, such as European settlement in North America. Nevertheless, if ecosystems were heavily influenced by native peoples prior to European settlement, conservation efforts may require active management rather than simple removal of or reductions in recent forms of disturbance. We used pre-European settlement land survey records (1859-1874) and contemporary vegetation surveys to assess changes over the past 150 years in tree species and habitat composition, forest density, and tree size structure on southern Vancouver Island and Saltspring Island, British Columbia, Canada. Several lines of evidence support the hypothesis that frequent historical burning by native peoples, and subsequent fire suppression, have played dominant roles in shaping this landscape. First, the relative frequency of fire-sensitive species (e.g., cedar [Thuja plicata]) has increased, whereas fire-tolerant species (e.g., Douglas-fir [Pseudotsuga menziesii]) have decreased. Tree density has increased 2-fold, and the proportion of the landscape in forest has greatly increased at the expense of open habitats (plains, savannas), which today contain most of the region's threatened species. Finally, the frequency distribution of tree size has shifted from unimodal to monotonically decreasing, which suggests removal of an important barrier to tree recruitment. In addition, although most of the open habitats are associated with Garry oak (Quercus garryana) at present, most of the open habitats prior to European settlement were associated with Douglas-fir, which suggests that the current focus on Garry oak as a flagship for the many rare species in savannas may be misguided. Overall, our results indicate that the maintenance and restoration of open habitats will require active management and that historical records can provide critical guidance to such

  12. Forest restoration at Redwood National Park: exploring prescribed fire alternatives to second-growth management: a case study

    Science.gov (United States)

    Engber, Eamon; Teraoka, Jason; van Mantgem, Phillip J.

    2017-01-01

    Almost half of Redwood National Park is comprised of second-growth forests characterized by high stand density, deficient redwood composition, and low understory biodiversity. Typical structure of young redwood stands impedes the recovery of old-growth conditions, such as dominance of redwood (Sequoia sempervirens (D. Don) Endl.), distinct canopy layers and diverse understory vegetation. Young forests are commonly comprised of dense, even-aged Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and redwood stump sprouts, with simple canopy structure and little understory development. Moreover, many of these young stands are believed to be vulnerable to disturbance in the form of drought, disease and fire. Silvicultural practices are increasingly being employed by conservation agencies to restore degraded forests throughout the coast redwood range; however, prescribed fire treatments are less common and potentially under-utilized as a restoration tool. We present an early synthesis from three separate management-scale prescribed fire projects at Redwood National Park spanning 1to 7 years post-treatment. Low intensity prescribed fire had minimal effect on overstory structure, with some mortality observed in trees smaller than 30 cm diameter. Moderate to high intensity fire may be required to reduce densities of larger Douglas-fir, the primary competitor of redwood in the Park’s second growth forests. Fine woody surface fuels fully recovered by 7 years post-burn, while recruitment of larger surface fuels was quite variable. Managers of coastal redwood ecosystems will benefit by having a variety of tools at their disposal for forest restoration and management.

  13. Geochemical results of a hydrothermally altered area at Baker Creek, Blaine County, Idaho

    Science.gov (United States)

    Erdman, James A.; Moye, Falma J.; Theobald, Paul K.; McCafferty, Anne E.; Larsen, Richard K.

    2001-01-01

    The area immediately east of Baker Creek, Blaine County, Idaho, is underlain by a thick section of mafic to intermediate lava flows of the Eocene Challis Volcanic Group. Widespread propylitic alteration surrounds a zone of argillic alteration and an inner core of phyllic alteration. Silicified breccia is present along an east-trending fault within the zone of phyllic alteration. As part of a reconnaissance geochemical survey, soils and plants were sampled. Several species of plants (Douglas-fir [ Pseudotsuga menziesii ], mountain big sagebrush [ Artemisia tridentata ssp. vaseyana ], and elk sedge [ Carex geyerii ]) were collected from 10 upland localities and stream sediments, panned concentrates, and aquatic mosses were collected from 16 drainage basin localities all of which were generally within the area of alteration. Geochemical results yielded anomalous concentrations of molybenum, zinc, silver, and lead in at least half of the seven different sample media and of gold, thallium, arsenic, antimony, manganese, boron, cadmium, bismuth, copper, and beryllium in from one to four of the various media. Part of this suite of elements? silver, gold, arsenic, antimony, thallium, and manganese? suggests that the mineralization in the area is epithermal. Barite and pyrite (commonly botryoidal-framboidal) are widespread throughout the area sampled. Visible gold and pyromorphite (a secondary lead mineral) were identified in only one small drainage basin, but high levels of gold were detected in aquatic mosses over a larger area. Data from the upland and stream sampling indicate two possible mineralized areas. The first mineralized area was identified by a grab sample from an outcrop of quartz stockwork that contained 50 ppb Au, 1.5 ppm Ag, and 50 ppm Mo. Although the soil and plant species that were sampled in the area indicated mineralized bedrock, the Douglas-fir samples were the best indicators of the silver anomaly. The second possible mineralized area centers on the

  14. Soil charcoal from the plains to tundra in the Colorado Front Range

    Science.gov (United States)

    Sanford, R. L.; Licata, C.

    2010-12-01

    Throughout the forests of the central Rockies, soil charcoal from Holocene wildfires has been produced in response to wildland natural fire regimes. The extent and spatial distribution of soil charcoal production is poorly documented in this region, especially with regard to forests and shrublands at different elevations. Soil charcoal is a super-passive C pool derived from woody biomass that can be sequestered for millennia in forest soils. Recent research indicates that soil charcoal may promote enhanced soil fertility. Additionally, soil charcoal is an often overlooked component of soil C mass and flux. We hypothesize that differences in forest and shrubland fire regimes over the millennia have resulted in different soil charcoal amounts. Geospatial data were used to locate random sample plots in foothills shrublands (Cercocarpus montanus), and four forest types; ponderosa pine (Pinus ponderosa), Douglas-fir (Pseudotsuga menziesii), lodgepole pine (Pinus contorta) and spruce-fir (Picea engelmannii - Abies lasiocarpa). Sample plots were stratified to occur with the mid 200 m elevation band of each vegetation type with east aspect, and 10-30% slope. Soils were sampled widely at 0-10 cm depth and analyzed for total soil C and soil charcoal C via chemical digestion and dry combustion techniques. Overall, soil charcoal is four times more abundant in spruce-fir forests than in foothills shrublands (1.9 +/- 0.92 Mg C/ha versus 0.54 +/- 0.44 Mg C/ha). Soil charcoal is also abundant in lodgepole pine and ponderosa pine soils (1.4 +/- 1.02 Mg C/ha and 1.4 +/- 0.54 Mg C/ha respectively) but is less plentiful in Douglas-fir soils (1.0 +/- 0.67). Spruce-fir forests have the most above ground biomass, slower decomposition rates and a less frequent mean fire return interval than the other four forests, hence it makes sense that high per-fire rates of charcoal production would occur in the spruce-fir zone, given large amounts of surface fuels at the time of fire. In contrast

  15. Biophysical constraints on leaf expansion in a tall conifer.

    Science.gov (United States)

    Fredrick C. Meinzer; Barbara J. Bond; Jennifer A. Karanian

    2008-01-01

    The physiological mechanisms responsible for reduced extension growth as trees increase in height remain elusive. We evaluated biophysical constraints on leaf expansion in old-growth Douglas-fir (Psuedotsuga menziesii (Mirb.) Franco) trees. Needle elongation rates, plastic and elastic extensibility, bulk leaf water, (L...

  16. Riparian buffer and density management influences on microclimate of young headwater forests of Western Oregon.

    Science.gov (United States)

    Paul D. Anderson; David J. Larson; Samuel S. Chan

    2007-01-01

    Thinning of 30- to 70-year-old Douglas-fir (Psuedotsuga menziesii [Mirb.] Franco) stands is a common silvicultural activity on federal forest lands of the Pacific Northwest, United States. Empirical relationships among riparian functions, silvicultural treatments, and different riparian buffer widths are not well documented for small headwater...

  17. Understanding the long-term fire risks in forests affected by sudden oak death

    Science.gov (United States)

    Yana Valachovic; Chris Lee; Radoslaw Glebocki; Hugh Scanlon; J. Morgan Varner; David. Rizzo

    2010-01-01

    It is assumed that large numbers of dead and down tanoak in forests infested by Phytophthora ramorum contribute to increased fire hazard risk and fuel loading. We studied the impact of P. ramorum infestation on surface fuel loading, potential fire hazard, and potential fire behavior in Douglas-fir- (Pseudotsuga...

  18. Monoterpene concentration in Douglas-fir in relation to geographic location and resistance to attack by the Douglas-fir beetle

    Science.gov (United States)

    J.W. Hanover; M.M. Furniss

    1966-01-01

    The concentration of monoterpenes in Pinus monticola Dougl. has been shown to be genetically controlled (Hanover, in preparation). Genetic control of terpene concentration has been implied, also, from analyses of parents or interspecies hybrids in other species (Bannister et al. 1959; Williams and Bannister 1962; Smith 1964, and Forde 1964). Evidence...

  19. Assessments of Population Structure, Diversity, and Phylogeography of the Swiss Needle Cast Fungus (Phaeocryptopus gaeumannii in the U.S. Pacific Northwest

    Directory of Open Access Journals (Sweden)

    Patrick Bennett

    2016-01-01

    Full Text Available Swiss needle cast (SNC is a foliar disease of Douglas-fir (Pseudotsuga menziesii caused by Phaeocryptopus gaeumannii (Rohde Petrak. This fungus is endemic to western North America, where it has historically had little impact in native forests. However, increasing disease severity in western Oregon since the 1990s has prompted renewed interest in P. gaeumannii and SNC. For this study, we analyze multilocus microsatellite genotypes from 482 single-spore isolates from 68 trees across 14 sites in the western Coast Range of Oregon and southwestern Washington. This study assesses genotypic variation and genetic structure at several levels of population hierarchy. Despite the observation that most of the genetic variation occurred within subpopulations, our analyses detected significant differentiation at all hierarchical levels. Clustering among the 482 isolates based on genetic distance clearly supports the existence of two previously described cryptic lineages of P. gaeumannii in the western United States. The two lineages occur in varying proportions along latitudinal and longitudinal gradients in western Oregon and Washington, suggesting a relationship between climate and phylogeography. Sites near Tillamook, Oregon, where SNC is most severe, consist of sympatric subpopulations in which the two lineages comprise roughly equal proportions.

  20. Machine site preparation improves seedling performance on a high-elevation site in southwest Oregon

    International Nuclear Information System (INIS)

    McNabb, D.H.; Baker-Katz, K.; Tesch, S.D.

    1993-01-01

    Douglas-fir (Pseudotsuga menziesii) seedlings planted on areas receiving one of four site-preparation treatments (scarify, scarify/till, soil removal, and soil removal/till) and on unprepared control areas were compared for 5 yr at a high-elevation, nutrient-poor site in the western Siskiyou Mountains of southwest Oregon. Fifth-year survival of seedlings was at least 85% among machine-prepared plots, compared to 42% on control plots. Cover of competing vegetation remained less than 25% during the period for all machine treatments. In contrast, vegetation cover on control plots was 30% at the time of planting and increased to nearly 75% after 5 yr. Competing vegetation clearly impeded seedling performance. The effects of unusually droughty conditions at the time of planting in 1982 were examined further by interplanting additional seedlings in the soil-removal treatment in 1985. The interplanting was followed by more normal spring precipitation, and seedlings grew better over 5 yr than those planted in 1982. The slow recovery of competing vegetation and generally poor seedling growth on all treatments during both planting years are attributed to low soil fertility

  1. Sea sand disruption method (SSDM) as a valuable tool for isolating essential oil components from conifers.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Czapczyńska, Natalia B

    2011-11-01

    Essential oils are one of nature's most precious gifts with surprisingly potent and outstanding properties. Coniferous oils, for instance, are nowadays being used extensively to treat or prevent many types of infections, modify immune responses, soothe inflammations, stabilize moods, and to help ease all forms of non-acute pain. Given the broad spectrum of usage of coniferous essential oils, a fast, safe, simple, and efficient sample-preparation method is needed in the estimation procedure of essential oil components in fresh plant material. Generally, the time- and energy-consuming steam distillation (SD) is applied for this purpose. This paper will compare SD, pressurized liquid extraction (PLE), matrix solid-phase dispersion (MSPD), and the sea sand disruption method (SSDM) as isolation techniques to obtain aroma components from Scots pine (Pinus sylvestris), spruce (Picea abies), and Douglas fir (Pseudotsuga menziesii). According to the obtained data, SSDM is the most efficient sample preparation method in determining the essential oil composition of conifers. Moreover, SSDM requires small organic solvent amounts and a short extraction time, which makes it an advantageous alternative procedure for the routine analysis of coniferous oils. The superiority of SSDM over MSPD efficiency is ascertained, as there are no chemical interactions between the plant cell components and the sand. This fact confirms the reliability and efficacy of SSDM for the analysis of volatile oil components. Copyright © 2011 Verlag Helvetica Chimica Acta AG, Zürich.

  2. Tree-ring-based reconstruction of precipitation in the Bighorn Basin, Wyoming, since 1260 A.D

    Science.gov (United States)

    Gray, S.T.; Fastie, C.L.; Jackson, S.T.; Betancourt, J.L.

    2004-01-01

    Cores and cross sections from 79 Douglas fir (Pseudotsuga menziesii) and limber pine (Pinus flexilis) trees at four sites in the Bighorn Basin of north-central Wyoming and south-central Montana were used to develop a proxy for annual (June-June) precipitation spanning 1260-1998 A.D. The reconstruction exhibits considerable nonstationarity, and the instrumental era (post-1900) in particular fails to capture the full range of precipitation variability experienced in the past ???750 years. Both single-year and decadal-scale dry events were more severe before 1900. Dry spells in the late thirteenth and sixteenth centuries surpass both magnitude and duration of any droughts in the Bighorn Basin after 1900. Precipitation variability appears to shift to a higher-frequency mode after 1750, with 15-20-yr droughts becoming rare. Comparisons between instrumental and reconstructed values of precipitation and indices of Pacific basin variability reveal that precipitation in the Bighorn Basin generally responds to Pacific forcing in a manner similar to that of the southwestern United States (drier during La Nin??a events), but high country precipitation in areas surrounding the basin displays the opposite response (drier during El Nin??o events). ?? 2004 American Meteorological Society.

  3. An integrated tool to assess the role of new planting in PM10 capture and the human health benefits: A case study in London

    International Nuclear Information System (INIS)

    Tiwary, Abhishek; Sinnett, Danielle; Peachey, Christopher; Chalabi, Zaid; Vardoulakis, Sotiris; Fletcher, Tony; Leonardi, Giovanni; Grundy, Chris; Azapagic, Adisa; Hutchings, Tony R.

    2009-01-01

    The role of vegetation in mitigating the effects of PM 10 pollution has been highlighted as one potential benefit of urban greenspace. An integrated modelling approach is presented which utilises air dispersion (ADMS-Urban) and particulate interception (UFORE) to predict the PM 10 concentrations both before and after greenspace establishment, using a 10 x 10 km area of East London Green Grid (ELGG) as a case study. The corresponding health benefits, in terms of premature mortality and respiratory hospital admissions, as a result of the reduced exposure of the local population are also modelled. PM 10 capture from the scenario comprising 75% grassland, 20% sycamore maple (Acer pseudoplatanus L.) and 5% Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) was estimated to be 90.41 t yr -1 , equating to 0.009 t ha -1 yr -1 over the whole study area. The human health modelling estimated that 2 deaths and 2 hospital admissions would be averted per year. - A combination of models can be used to estimate particulate matter concentrations before and after greenspace establishment and the resulting benefits to human health.

  4. Phytolith analysis as a tool for palaeo-environmental studies: a case study of the reconstruction of the historical extent of oak savanna in the Willamette Valley, Oregon

    Science.gov (United States)

    Kirchholtes, Renske; van Mourik, Jan; Johnson, Bart

    2014-05-01

    Landscape-level restorations can be costly, so the effectiveness of the approach and the objectives of the restoration should be supported by a comprehensive investigation. The goal of the research presented here is to provide the basis for such a restoration effort using phytolith analyses. Fire suppression and loss of indigenous burning in the Willamette Valley, Oregon (USA) has led to near disappearance of the Oregon white oak savanna. Under suppressed fire regimes the shade-intolerant Garry oaks (Quercus garryana) are outcompeted by Douglas-fir (Pseudotsuga menziesii). As a consequence, the Oregon white oak savanna has been reduced to floristic reconstructions (pollen and spores) are seldom preserved in the dry, oxidized sediments of savannahs, meaning an alternative line of evidence is required for their historical study. Phytoliths are small yet robust silica particles produced by most plants. Many phytoliths take on cell shapes diagnostic of specific plant lineages, acting as indicators of their past presence. Unlike pollen grains, phytoliths readily preserve in well-drained soils during intermittent dry periods characteristic of sites such as the Jim's Creek research area. By reconstructing locality-scale pre-settlement vegetation patterns at the Jim's Creek Research Area using phytoliths, we confirm the broader-scale pattern of tree encroachment. However, phytolith assemblages from over 150 years ago document the presence of pines and firs, suggesting savannas in the Willamette Valley were not necessarily always dominated by oaks.

  5. Instrumenting the Conifers: A Look at Daily Tree Growth and Locally Observed Environmental Conditions Across Four Mountain Sites in the Central Great Basin, USA

    Science.gov (United States)

    Strachan, S.; Biondi, F.; Johnson, B. G.

    2012-12-01

    Tree growth is often used as a proxy for past environmental conditions or as an indicator of developing trends. Reconstructions of drought, precipitation, temperature, and other phenomena derived from tree-growth indices abound in scientific literature aimed at informing policy makers. Observations of tree recruitment or death in treeline populations are frequently tied to climatic fluctuation in cause-effect hypotheses. Very often these hypotheses are based on statistical relationships between annual-to-seasonal tree growth measurements and some environmental parameter measured or modeled off-site. Observation of daily tree growth in conjunction with in-situ environmental measurements at similar timescales takes us one step closer to quantifying the uncertainty in reconstruction or predictive studies. In four separate sites in two different mountain ranges in the central Great Basin, co-located observations of conifer growth activity and local atmospheric and soils conditions have been initiated. Species include Pinus longaeva (Great Basin bristlecone pine), Pinus flexilis (limber pine), Picea engelmannii (Engelmann spruce), Pinus monophylla (singleleaf pinyon pine), Pinus ponderosa (ponderosa pine), Abies concolor (white fir), and Pseudotsuga menziesii (Douglas-fir). Measurements of sub-hourly tree radial length change and sap flow activity are compared with a suite of in-situ observations including air temperature, precipitation, photosynthetically-active radiation (PAR), relative humidity, soil temperature, and soil moisture/water content. Subalpine study site located at 3360 m elevation in the Snake Range, Nevada

  6. Evaluation of methods for the physical characterization of the fine particle emissions from two residential wood combustion appliances

    Science.gov (United States)

    Kinsey, John S.; Kariher, Peter H.; Dong, Yuanji

    The fine particle emissions from a U. S. certified non-catalytic wood stove and a zero-clearance fireplace burning Quercus rubra L. (northern red oak) and Pseudotsuga menziesii (Douglas fir) cordwood each at two different moisture levels were determined. Emission testing was performed using both time-integrated and continuous instrumentation for total particle mass, particle number, particle size distribution, and fixed combustion gases using an atmospheric wind tunnel, full-flow laboratory dilution tunnel, and dilution stack sampler with a comparison made between the three dilution systems and two sampling filter types. The total mass emission factors (EFs) for all dilution systems and filter media are extremely variable ranging from fireplace emissions burning wet oak averaged 11 g kg -1. A substantial number of ultrafine particles in the accumulation size range were also observed during all tests as determined by an Electrical Low Pressure Impactor (ELPI) and Scanning Mobility Particle Sizer. The PM-2.5 (particles ≤2.5 μm in aerodynamic diameter) fractions determined from the ELPI electrometer data ranged from 93 to 98% (mass) depending on appliance type as reported previously by Hays et al. (Aerosol Science, 34, 1061, 2003).

  7. Building Resilience into Sitka Spruce (Picea sitchensis (Bong. Carr. Forests in Scotland in Response to the Threat of Climate Change

    Directory of Open Access Journals (Sweden)

    Andrew D. Cameron

    2015-02-01

    Full Text Available It is expected that a warming climate will have an impact on the future productivity of European spruce forests. In Scotland, Sitka spruce (Picea sitchensis (Bong. Carr. dominates the commercial forestry sector and there is growing pressure to develop alternative management strategies to limit potential economic losses through climate change. This review considers management options to increase the resilience of Sitka spruce dominated forests in Scotland. Given the considerable uncertainty over the potential long-term impacts of climate change, it is recommended that Sitka spruce should continue to be planted where it already grows well. However, new planting and restocking should be established in mixtures where silviculturally practicable, even if no-thin regimes are adopted, to spread future risks of damage. Three potentially compatible species with Sitka spruce are western hemlock (Tsuga heterophylla (Raf. Sarg., grand fir (Abies grandis (Lamb. Lindl. and Douglas fir (Pseudotsuga menziesii (Mirb. Franco and all form natural mixtures in its native range in North America. The predicted windier climate will require a range of management inputs, such as early cutting of extraction racks and early selective thinning, to improve stability. The potential to improve resilience to particularly abiotic damage through transforming even-aged stands into irregular structures and limiting the overall size of the growing stock is discussed.

  8. Application of Proteomics to the Study of Pollination Drops

    Directory of Open Access Journals (Sweden)

    Natalie Prior

    2013-04-01

    Full Text Available Premise of the study: Pollination drops are a formative component in gymnosperm pollen-ovule interactions. Proteomics offers a direct method for the discovery of proteins associated with this early stage of sexual reproduction. Methods: Pollination drops were sampled from eight gymnosperm species: Chamaecyparis lawsoniana (Port Orford cedar, Ephedra monosperma, Ginkgo biloba, Juniperus oxycedrus (prickly juniper, Larix ×marschlinsii, Pseudotsuga menziesii (Douglas-fir, Taxus ×media, and Welwitschia mirabilis. Drops were collected by micropipette using techniques focused on preventing sample contamination. Drop proteins were separated using both gel and gel-free methods. Tandem mass spectrometric methods were used including a triple quadrupole and an Orbitrap. Results: Proteins are present in all pollination drops. Consistency in the protein complement over time was shown in L. ×marschlinsii. Representative mass spectra from W. mirabilis chitinase peptide and E. monosperma serine carboxypeptidase peptide demonstrated high quality results. We provide a summary of gymnosperm pollination drop proteins that have been discovered to date via proteomics. Discussion: Using proteomic methods, a dozen classes of proteins have been identified to date. Proteomics presents a way forward in deepening our understanding of the biological function of pollination drops.

  9. Structure and Composition of Old-Growth and Unmanaged Second-Growth Riparian Forests at Redwood National Park, USA

    Directory of Open Access Journals (Sweden)

    Christopher R. Keyes

    2014-02-01

    Full Text Available Restoration of second-growth riparian stands has become an important issue for managers of redwood (Sequoia sempervirens [D. Don] Endl. forest reserves. Identifying differences between old-growth and second-growth forest vegetation is a necessary step in evaluating restoration needs and targets. The objective of this study was to characterize and contrast vegetation structure and composition in old-growth and unmanaged second-growth riparian forests in adjacent, geomorphologically similar watersheds at Redwood National Park. In the old-growth, redwood was the dominant overstory species in terms of stem density, basal area, and importance values. Second-growth was dominated by red alder (Alnus rubra Bong., Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco, and redwood. Understory species were similar in both forests, with several key differences: Oxalis oregana Nutt. and Trillium ovatum Pursh had greater importance values in the old-growth, and Vaccinium parvifolium Sm., Dryopteris spp. and sedges Carex spp. had greater importance values in the second-growth. Notable differences in structure and composition suggest that restoration practices such as thinning could expedite the acquisition of old-growth characteristics in second-growth riparian forests.

  10. Crown dynamics and wood production of Douglas-fir trees in an old-growth forest

    Science.gov (United States)

    H. Roaki Ishii; Stephen C. Sillett; Allyson L. Carroll

    2017-01-01

    Large trees are the most prominent structural features of old-growth forests, which are considered to be globally important carbon sinks. Because of their large size, estimates of biomass and growth of large trees are often based on ground-level measurements (e.g., diameter at breast height, DBH) and little is known about growth dynamics within the crown. As trees...

  11. Monitoring tree mortality in mature Douglas-fir forests: size and species matter

    Science.gov (United States)

    Background/Question/MethodsA regional increase in tree mortality rates associated with climate change will influence forest health and ecosystem services, including water quality and quantity. In recent decades, accelerated tree mortality has occurred in some, but not all, fores...

  12. Pretreatment of forest residues of Douglas fir by wet explosion for enhanced enzymatic saccharification.

    Science.gov (United States)

    Biswas, Rajib; Teller, Philip J; Ahring, Birgitte K

    2015-09-01

    The logging and lumbering industry in the Pacific Northwest region generates huge amount of forest residues, offering an inexpensive raw material for biorefineries. Wet explosion (WEx) pretreatment was applied to the recalcitrant biomass to optimize process conditions including temperature (170-190 °C), time (10-30 min), and oxygen loading (0.5-7.5% of DM) through an experimental design. Optimal pH for enzymatic hydrolysis of the optimized samples and a complete mass balance have been evaluated. Results indicated that cellulose digestibility improved in all conditions tested with maximum digestibility achieved at 190 °C, time 30 min, and oxygen loading of 7.5%. Glucose yield at optimal pH of 5.5 was 63.3% with an excellent recovery of cellulose and lignin of 99.9% and 96.3%, respectively. Hemicellulose sugars recovery for xylose and mannose was found to be 69.2% and 76.0%, respectively, indicating that WEx is capable of producing relative high sugar yield even from the recalcitrant forest residues. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Douglas-fir nutrients and terpenes as potential factors influencing western spruce budworm defoliation

    Science.gov (United States)

    Karen M. Clancy

    1991-01-01

    Variation in levels of herbivory within and among plants can be attributed to many mechanisms, such as differences in a) host nutritional quality, b) suitability of the physical environment, and c) abundance of competitor consumers or natural enemies (Mattson et al. 1982, Denno and McClure 1983, Mattson and Scriber 1987, Clancy et al. 1988a, 1988b, Mattson et al. 1988...

  14. Simulation of growth and competition in mixed stands of Douglas-fir and beech

    NARCIS (Netherlands)

    Bartelink, H.H.

    1998-01-01

    For a long time, the emphasis in silviculture in Western Europe was solely on even-aged, monospecific stands; many empirical stand-level growth models were developed and successfully used for managing such stands. In contrast, no generally accepted growth and yield approach has emerged so

  15. 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...

  16. Songbird response to alternative forest density management in young Douglas-fir stands

    Science.gov (United States)

    Joan C. Hagar

    2013-01-01

    Th inning has been increasingly used in the Pacifi c Northwest to restore structural and biological diversity to densely-stocked young- to mid-aged forests that have been previously intensively managed for timber production. In the short term, thinning promotes development of understory vegetation, which in turn can increase habitat diversity for wildlife, particularly...

  17. Genotype * environment interaction: a case study for Douglas-fir in western Oregon.

    Science.gov (United States)

    Robert K. Campbell

    1992-01-01

    Unrecognized genotype x environment interactions (g,e) can bias genetic-gain predictions and models for predicting growth dynamics or species perturbations by global climate change. This study tested six sets of families in 10 plantation sites in a 78-thousand-hectare breeding zone. Plantation differences accounted for 71 percent of sums of squares (15-year heights),...

  18. Pythium and Fusarium Species Associated with Production of Douglas-Fir Seedlings

    Science.gov (United States)

    Methyl bromide has long been used to control Pythium and Fusarium spp. in conifer nurseries in the Pacific Northwest. However, alternative fumigants are now necessary as methyl bromide is an ozone-depleting agent. The efficacy of metam sodium, dimethyl disulfide, and methyl iodide against Pythium ...

  19. Gene activity test determines cold tolerance in Douglas-fir seedlings

    Science.gov (United States)

    Peter A. Balk; Diane L. Haase; Monique F. van Wordragen

    2008-01-01

    Forest tree nurseries rely on a tight scheduling of operations to be able to deliver vigorous seedlings to the planting site. Cooler or freezer storage is often used to maintain planting stock in an inactive condition and to ensure a plant supply for geographically diverse planting sites, which is a requirement for large-scale or internationally operating nurseries....

  20. Soil acidification effects on fine root growth of Douglas-fir on sandy soils

    NARCIS (Netherlands)

    Olsthoorn, A.F.M.

    1998-01-01

    The ammonium sulphate deposited in forest ecosystems in the Netherlands as a result of air pollution currently exceeds 80 kg N ha -1yr -1locally. To study the influence of this air pollution on fine root density and its dynamics, fine root

  1. Major outbreaks of the Douglas-fir tussock moth in Oregon and California.

    Science.gov (United States)

    Boyd E. Wickman; Richard R. Mason; C.G. Thompson

    1973-01-01

    Case histories of five tussock moth outbreaks that occurred in California and Oregon between 1935 and 1965 are discussed. Information is given on the size and duration of the outbreaks, the presence of natural control agents and the damage caused. Most of the outbreaks were eventually treated with DDT. However, enough information was available from untreated portions...

  2. The role of organic matter as a source of nitrogen in Douglas-fir forest soils.

    Science.gov (United States)

    Robert F. Tarrant

    1948-01-01

    The organic material supplied the forest soil by deposits of needles, deadwood and roots, and soil insect remains, decomposes to form humus, defined as the plant and animal residues of the soil, fresh surface litter excluded, which are undergoing evident decomposition (2). This decomposition is necessary before the nutrient elements contained in the organic litter can...

  3. Age trends in Douglas-fir genetic parameters and implications for optimum selection age.

    Science.gov (United States)

    G.R. Johnson; R.A. Sniezko; N.L. Mandel

    1997-01-01

    rends in genetic variation were examined over 51 progeny test sites throughout western Oregon. Narrow sense heritabilities for height and diameter showed an increasing trend to age 25, the oldest age examined. Before age 10, height heritabilities were relatively unstable. Type B site-site genetic correlations increased slowly with age for height and remained relatively...

  4. When the douglas-firs were counted: The beginning of the Forest Survey

    Science.gov (United States)

    Ivan Doig

    1976-01-01

    The wonders which Phil Briegleb remembered from that stint of work - the dark green spill of forest from ridgeline to valley floor, the colonnade of giant boles crowding acre upon acre, the Depression-staving paycheck earned by sizing up this big timber - may have been grand, all right, but no more so than the language which spelled out the project. The Forest Survey...

  5. Heat sterilization time of ponderosa pine and Douglas-fir boards and square timbers

    Science.gov (United States)

    William T. Simpson; Xiping Wang; Steve Verrill

    2003-01-01

    To prevent the unintentional transfer of insects and pathogens during world trade, wood products are often heat sterilized. The general requirement is that the center of the wood configuration be held at 133°F (56°C) for 30 min. However, many factors can affect the time required to reach this temperature. This study explored several of these factors, including...

  6. The impacts of water stress on phloem transport in Douglas-fir trees

    Science.gov (United States)

    David Woodruff

    2014-01-01

    Despite the critical role that phloem plays in a number of plant functional processes and the potential impact of water stress on phloem structural and phloem sap compositional characteristics, little research has been done to examine how water stress influences phloem transport. The objectives of this study were to develop a more accurate understanding of how water...

  7. Simulation of forest growth, applied to douglas fir stands in the Netherlands

    NARCIS (Netherlands)

    Mohren, G.M.J.

    1987-01-01

    Forest growth in relation to weather and soils is studied using a physiological simulation model. Growth potential depends on physiological characteristics of the plant species in combination with ambient weather conditions (mainly temperature and incoming radiation). For a given site, growth may be

  8. Tolerance to multiple climate stressors: a case study of Douglas-fir drought and cold hardiness

    Science.gov (United States)

    Sheel Bansal; Connie Harrington; Brad St. Clair

    2016-01-01

    1. Drought and freeze events are two of the most common forms of climate extremes which result in tree damage or death, and the frequency and intensity of both stressors may increase with climate change. Few studies have examined natural covariation in stress tolerance traits to cope with multiple stressors among wild plant populations. 2. We assessed the...

  9. Tree damage from skyline logging in a western larch/Douglas-fir stand

    Science.gov (United States)

    Robert E. Benson; Michael J. Gonsior

    1981-01-01

    Damage to shelterwood leave trees and to understory trees in shelterwood and clearcut logging units logged with skyline yarders was measured, and related to stand conditions, harvesting specifications, and yarding system-terrain interactions. About 23 percent of the marked leave trees in the shelterwood units were killed in logging, and about 10 percent had moderate to...

  10. Changes in tracheid and ray traits in fire scars of North American conifers and their ecophysiological implications

    Science.gov (United States)

    Arbellay, Estelle; Stoffel, Markus; Sutherland, Elaine K.; Smith, Kevin T.; Falk, Donald A.

    2014-01-01

    Background and Aims Fire scars have been widely used as proxies for the reconstruction of fire history; however, little is known about the impact of fire injury on wood anatomy. This study investigates changes in tracheid and ray traits in fire scars of Douglas fir (Pseudotsuga menziesii), western larch (Larix occidentalis) and ponderosa pine (Pinus ponderosa), and discusses their ecophysiological implications for tree recovery from fire. Methods Transverse and tangential microsections were prepared for light microscopy and image analysis. Measurements of tracheids and rays were made in the three spatial dimensions: axially (at different section heights), radially (in different rings) and tangentially (with increasing distance from the wound margin). Key Results Changes were strongest in the first year after fire injury, with a decrease in tracheid size (by 25–30 %) and an increase in tracheid density (by 21–53 %) for the three species. In addition, an increase in ray size (by 5–27 %) and an increase in ray density (by 19–36 %) were found in P. menziesii and L. occidentalis. Changes were comparable along the fire-injured stem and were often most marked close to the fire scar. Conclusions The differentiation after fire injury of narrower and more numerous tracheids expresses a trade-off between hydraulic safety and hydraulic efficiency, while that of larger and more numerous rays serves compartmentalization and wound closure, mechanical strength and defence responses. Pinus ponderosa does not generally produce more ray tissue after fire injury and thus appears to be more adapted to fire. PMID:24941999

  11. The relationship between tree height and leaf area: sapwood area ratio.

    Science.gov (United States)

    McDowell, N; Barnard, H; Bond, B; Hinckley, T; Hubbard, R; Ishii, H; Köstner, B; Magnani, F; Marshall, J; Meinzer, F; Phillips, N; Ryan, M; Whitehead, D

    2002-06-01

    The leaf area to sapwood area ratio (A l :A s ) of trees has been hypothesized to decrease as trees become older and taller. Theory suggests that A l :A s must decrease to maintain leaf-specific hydraulic sufficiency as path length, gravity, and tortuosity constrain whole-plant hydraulic conductance. We tested the hypothesis that A l :A s declines with tree height. Whole-tree A l :A s was measured on 15 individuals of Douglas-fir (Pseudotsuga menziesii var. menziesii) ranging in height from 13 to 62 m (aged 20-450 years). A l :A s declined substantially as height increased (P=0.02). Our test of the hypothesis that A l :A s declines with tree height was extended using a combination of original and published data on nine species across a range of maximum heights and climates. Meta-analysis of 13 whole-tree studies revealed a consistent and significant reduction in A l :A s with increasing height (P<0.05). However, two species (Picea abies and Abies balsamea) exhibited an increase in A l :A s with height, although the reason for this is not clear. The slope of the relationship between A l :A s and tree height (ΔA l :A s /Δh) was unrelated to mean annual precipitation. Maximum potential height was positively correlated with ΔA l :A s /Δh. The decrease in A l :A s with increasing tree size that we observed in the majority of species may be a homeostatic mechanism that partially compensates for decreased hydraulic conductance as trees grow in height.

  12. Interactions between leaf nitrogen status and longevity in relation to N cycling in three contrasting European forest canopies

    Science.gov (United States)

    Wang, L.; Ibrom, A.; Korhonen, J. F. J.; Arnoud Frumau, K. F.; Wu, J.; Pihlatie, M.; Schjoerring, J. K.

    2012-07-01

    Seasonal and spatial variations in foliar nitrogen (N) parameters were investigated in three European forests with different tree species, viz. beech (Fagus sylvatica L.), Douglas fir (Pseudotsuga menziesii, Mirb., Franco) and Scots pine (Pinus sylvestris L.) in Denmark, The Netherlands and Finland, respectively. This was done in order to obtain information about functional acclimation, tree internal N conservation and its relevance for both ecosystem internal N cycling and foliar N exchange with the atmosphere. Leaf N pools generally showed much higher seasonal variability in beech trees than in the coniferous canopies. The concentrations of N and chlorophyll in the beech leaves were synchronized with the seasonal course of solar radiation implying close physiological acclimation, which was not observed in the coniferous needles. During phases of intensive N metabolism in the beech leaves, the NH4+ concentration rose considerably. This was compensated for by a strong pH decrease resulting in relatively low Γ values (ratio between tissue NH4+ and H+). The Γ values in the coniferous were even smaller than in beech, indicating low probability of NH3 emissions from the foliage to the atmosphere as an N conserving mechanism. The reduction in foliage N content during senescence was interpreted as N re-translocation from the senescing leaves into the rest of the trees. The N re-translocation efficiency (ηr) ranged from 37 to 70% and decreased with the time necessary for full renewal of the canopy foliage. Comparison with literature data from in total 23 tree species showed a general tendency for ηr to on average be reduced by 8% per year the canopy stays longer, i.e. with each additional year it takes for canopy renewal. The boreal pine site returned the lowest amount of N via foliage litter to the soil, while the temperate Douglas fir stand which had the largest peak canopy N content and the lowestηr returned the highest amount of N to the soil. These results

  13. Delayed conifer mortality after fuel reduction treatments: Interactive effects of fuel, fire intensity, and bark beetles

    Science.gov (United States)

    Youngblood, A.; Grace, J.B.; Mciver, J.D.

    2009-01-01

    Many low-elevation dry forests of the western United States contain more small trees and fewer large trees, more down woody debris, and less diverse and vigorous understory plant communities compared to conditions under historical fire regimes. These altered structural conditions may contribute to increased probability of unnaturally severe wildfires, susceptibility to uncharacteristic insect outbreaks, and drought-related mortality. Broad-scale fuel reduction and restoration treatments are proposed to promote stand development on trajectories toward more sustainable structures. Little research to date, however, has quantified the effects of these treatments on the ecosystem, especially delayed and latent tree mortality resulting directly or indirectly from treatments. In this paper, we explore complex hypotheses relating to the cascade of effects that influence ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) mortality using structural equation modeling (SEM). We used annual census and plot data through six growing seasons after thinning and four growing seasons after burning from a replicated, operational-scale, completely randomized experiment conducted in northeastern Oregon, USA, as part of the national Fire and Fire Surrogate study. Treatments included thin, burn, thin followed by burn (thin+burn), and control. Burn and thin+burn treatments increased the proportion of dead trees while the proportion of dead trees declined or remained constant in thin and control units, although the density of dead trees was essentially unchanged with treatment. Most of the new mortality (96%) occurred within two years of treatment and was attributed to bark beetles. Bark beetle-caused tree mortality, while low overall, was greatest in thin + burn treatments. SEM results indicate that the probability of mortality of large-diameter ponderosa pine from bark beetles and wood borers was directly related to surface fire severity and bole charring, which in

  14. Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region

    Science.gov (United States)

    2008-04-01

    elevations in the local area dominated by conifers (e.g., spruce (Picea), fir (Abies), hemlock (Tsuga), Douglas-fir (Pseudotsuga), coast redwood...annual temperature is 33 to 62 ºF (1 to 17 ºC) (USDA Natural Resources Conservation Service 2006a). Low-elevation mixed conifer forests are...redox concentrations and those that do not, for hue 10YR, to meet the definition of a depleted matrix. Due to inaccurate color reproduction , do not use

  15. Environmental Impact Research Program. Ruffed Grouse (Bonasa umbellus) Section 4.1.1, US Army Corps of Engineers Wildlife Resources Management Manual.

    Science.gov (United States)

    1986-07-01

    tors in most populations (Edminster 1954, Gullion and Marshall 1968). However, hunting may depress grouse numbers on areas that receive intensive...in the diversity of ruffed grouse diets. Clover and other green leafy material and the fruits of Arctostaphylos, cranberry , and meadow rue contribute...Christmas fern Polystichum acrostichoides Clover Trifoliwn spp. Cranberry Viburnum edule Dandelion Taraxaum spp. Dogwood Corfus spp. Douglas fir Pseudotsuga

  16. Installation Restoration Program. Phase 1. Records Search, United States Air Force Academy, Colorado Springs, Colorado

    Science.gov (United States)

    1984-12-01

    SOURCE: U.S. Air Force Academy, Tab A-i, Environmental Narrative Woodland Biome Zone (6000-7000 feet) SPECIES U Trees 3 . ’Ponderosa pine Pinus ...Highest Frequency of Occurrence U SPECIES 3 Trees 1. Ponderosa pine Pinus ponderosa var scopulorum 3 2. Douglas fir Pseudotsuga menzlesii 3. White...LYSIMETER A vacuum operated sampling device used for extracting pore waters at various I depths within the unsaturated zone. I G-6 I I * i MEK Methyl Ethyl

  17. Finding of No Significant Impact (FONSI): Environmental Assessment of the Farish Recreation Area Observatory and Cabin Construction

    Science.gov (United States)

    2011-12-21

    Montane forest comprises approximately 34 percent of the study area. Montane forests within the study area are a mix of Ponderosa pine ( Pinus ...ponderosa), limber pine ( Pinus flexilis), lodgepole pine ( Pinus contorta), and Engelmann spruce (Picea engelmannii) in dry areas. Douglas-fir (Pseudotsuga... drought stress. El Paso County fire bans are enforced within Farish. The USAFA has instituted thinning operations to mitigate fire dangers (Strohm

  18. Physiological responses by juvenile Egregia menziesii (Phaeophyta) to simulated effects of wave action: Carbon and nitrogen uptake and carbon partitioning

    International Nuclear Information System (INIS)

    Kraemer, G.P.

    1990-01-01

    Although biomechanical and morphological adaptations to different wave energy regimes are well known, the physiological mechanisms behind, and the trigger(s) eliciting these responses, are not. Egregia menziesii (Turn.) Aresch. juveniles (5-10 cm) were incubated for 4 hr in chambers containing 14 C-labeled bicarbonate, under combinations of two levels of nutrient concentration and two levels of tensile force. Whole tissue and cell wall material (=cellulose + alginates) were examined for 14 C incorporation. Tensile force elicited greater incorporation into whole tissue and directed more carbon into the cell wall compartment. Ambient nutrient levels and tissue age both had inverse effects on carbon partitioning into cell wall material. Tensile force also reduced nitrate uptake rates by about 50%

  19. Plants promote mating and dispersal of the human pathogenic fungus Cryptococcus.

    Directory of Open Access Journals (Sweden)

    Deborah J Springer

    Full Text Available Infections due to Cryptococcus are a leading cause of fungal infections worldwide and are acquired as a result of environmental exposure to desiccated yeast or spores. The ability of Cryptococcus to grow, mate, and produce infectious propagules in association with plants is important for the maintenance of the genetic diversity and virulence factors important for infection of animals and humans. In the Western United States and Canada, Cryptococcus has been associated with conifers and tree species other than Eucalyptus; however, to date Cryptococcus has only been studied on live Arabidopsis thaliana, Eucalyptus sp., and Terminalia catappa (almond seedlings. Previous research has demonstrated the ability of Cryptococcus to colonize live plants, leaves, and vasculature. We investigated the ability of Cryptococcus to grow on live seedlings of the angiosperms, A. thaliana, Eucalyptus camaldulensis, Colophospermum mopane, and the gymnosperms, Pseudotsuga menziesii (Douglas fir, and Tsuga heterophylla (Western hemlock. We observed a broad-range ability of Cryptococcus to colonize both traditional infection models as well as newly tested conifer species. Furthermore, C. neoformans, C. deneoformans, C. gattii (VGI, C. deuterogattii (VGII and C. bacillisporus (VGIII were able to colonize live plant leaves and needles but also undergo filamentation and mating on agar seeded with plant materials or in saprobic association with dead plant materials. The ability of Cryptococcus to grow and undergo filamentation and reproduction in saprobic association with both angiosperms and gymnosperms highlights an important role of plant debris in the sexual cycle and exposure to infectious propagules. This study highlights the broad importance of plants (and plant debris as the ecological niche and reservoirs of infectious propagules of Cryptococcus in the environment.

  20. Measurement of snow interception and canopy effects on snow accumulation and melt in a mountainous maritime climate, Oregon, United States

    Science.gov (United States)

    Storck, Pascal; Lettenmaier, Dennis P.; Bolton, Susan M.

    2002-11-01

    The results of a 3 year field study to observe the processes controlling snow interception by forest canopies and under canopy snow accumulation and ablation in mountain maritime climates are reported. The field study was further intended to provide data to develop and test models of forest canopy effects on beneath-canopy snowpack accumulation and melt and the plot and stand scales. Weighing lysimeters, cut-tree experiments, and manual snow surveys were deployed at a site in the Umpqua National Forest, Oregon (elevation 1200 m). A unique design for a weighing lysimeter was employed that allowed continuous measurements of snowpack evolution beneath a forest canopy to be taken at a scale unaffected by variability in canopy throughfall. Continuous observations of snowpack evolution in large clearings were made coincidentally with the canopy measurements. Large differences in snow accumulation and ablation were observed at sites beneath the forest canopy and in large clearings. These differences were not well described by simple relationships between the sites. Over the study period, approximately 60% of snowfall was intercepted by the canopy (up to a maximum of about 40 mm water equivalent). Instantaneous sublimation rates exceeded 0.5 mm per hour for short periods. However, apparent average sublimation from the intercepted snow was less than 1 mm per day and totaled approximately 100 mm per winter season. Approximately 72 and 28% of the remaining intercepted snow was removed as meltwater drip and large snow masses, respectively. Observed differences in snow interception rate and maximum snow interception capacity between Douglas fir (Pseudotsuga menziesii), white fir (Abies concolor), ponderosa pine (Pinus ponderosa), and lodgepole pine (Pinus contorta) were minimal.

  1. Seasonal trends of biogenic terpene emissions.

    Science.gov (United States)

    Helmig, Detlev; Daly, Ryan Woodfin; Milford, Jana; Guenther, Alex

    2013-09-01

    Biogenic volatile organic compound (BVOC) emissions from six coniferous tree species, i.e. Pinus ponderosa (Ponderosa Pine), Picea pungens (Blue Spruce), Pseudotsuga menziesii (Rocky Mountain Douglas Fir) and Pinus longaeva (Bristlecone Pine), as well as from two deciduous species, Quercus gambelii (Gamble Oak) and Betula occidentalis (Western River Birch) were studied over a full annual growing cycle. Monoterpene (MT) and sesquiterpene (SQT) emissions rates were quantified in a total of 1236 individual branch enclosure samples. MT dominated coniferous emissions, producing greater than 95% of BVOC emissions. MT and SQT demonstrated short-term emission dependence with temperature. Two oxygenated MT, 1,8-cineol and piperitone, were both light and temperature dependent. Basal emission rates (BER, normalized to 1000μmolm(-2)s(-1) and 30°C) were generally higher in spring and summer than in winter; MT seasonal BER from the coniferous trees maximized between 1.5 and 6.0μgg(-1)h(-1), while seasonal lows were near 0.1μgg(-1)h(-1). The fractional contribution of individual MT to total emissions was found to fluctuate with season. SQT BER measured from the coniferous trees ranged from emissions modeling, was not found to exhibit discernible growth season trends. A seasonal correction factor proposed by others in previous work to account for a sinusoidal shaped emission pattern was applied to the data. Varying levels of agreement were found between the data and model results for the different plant species seasonal data sets using this correction. Consequently, the analyses on this extensive data set suggest that it is not feasible to apply a universal seasonal correction factor across different vegetation species. A modeling exercise comparing two case scenarios, (1) without and (2) with consideration of the seasonal changes in emission factors illustrated large deviations when emission factors are applied for other seasons than those in which they were experimentally

  2. Millennial precipitation reconstruction for the Jemez Mountains, New Mexico, reveals changing drought signal

    Science.gov (United States)

    Touchan, Ramzi; Woodhouse, Connie A.; Meko, David M.; Allen, Craig D.

    2011-01-01

    Drought is a recurring phenomenon in the American Southwest. Since the frequency and severity of hydrologic droughts and other hydroclimatic events are of critical importance to the ecology and rapidly growing human population of this region, knowledge of long-term natural hydroclimatic variability is valuable for resource managers and policy-makers. An October–June precipitation reconstruction for the period AD 824–2007 was developed from multi-century tree-ring records of Pseudotsuga menziesii (Douglas-fir), Pinus strobiformis (Southwestern white pine) and Pinus ponderosa (Ponderosa pine) for the Jemez Mountains in Northern New Mexico. Calibration and verification statistics for the period 1896–2007 show a high level of skill, and account for a significant portion of the observed variance (>50%) irrespective of which period is used to develop or verify the regression model. Split-sample validation supports our use of a reconstruction model based on the full period of reliable observational data (1896–2007). A recent segment of the reconstruction (2000–2006) emerges as the driest 7-year period sensed by the trees in the entire record. That this period was only moderately dry in precipitation anomaly likely indicates accentuated stress from other factors, such as warmer temperatures. Correlation field maps of actual and reconstructed October–June total precipitation, sea surface temperatures and 500-mb geopotential heights show characteristics that are similar to those indicative of El Niño–Southern Oscillation patterns, particularly with regard to ocean and atmospheric conditions in the equatorial and north Pacific. Our 1184-year reconstruction of hydroclimatic variability provides long-term perspective on current and 20th century wet and dry events in Northern New Mexico, is useful to guide expectations of future variability, aids sustainable water management, provides scenarios for drought planning and as inputs for hydrologic models under a

  3. Precipitation Reconstructions and Periods of Drought in the Upper Green River Basin, Wyoming, USA

    Science.gov (United States)

    Follum, M.; Barnett, A.; Bellamy, J.; Gray, S.; Tootle, G.

    2008-12-01

    Due to recent drought and stress on water supplies in the Colorado River Compact States, more emphasis has been placed on the study of water resources in the Upper Green River Basin (UGRB) of Wyoming, Utah, and Colorado. The research described here focuses on the creation of long-duration precipitation records for the UGRB using tree-ring chronologies. When combined with existing proxy streamflow reconstructions and drought frequency analysis, these records offer a detailed look at hydrologic variability in the UGRB. Approximately thirty-three existing tree ring chronologies were analyzed for the UGRB area. Several new tree ring chronologies were also developed to enhance the accuracy and the geographical diversity of the resulting tree-ring reconstructions. In total, three new Douglas-fir (Pseudotsuga menziesii) and four new limber pine (Pinus flexilis) sites were added to the available tree-ring chronologies in this area. Tree-ring based reconstructions of annual (previous July through current June) precipitation were then created for each of the seventeen sub-watersheds in the UGRB. Reconstructed precipitation records extend back to at least 1654 AD, with reconstructions for some sub-basins beginning pre-1500. Variance explained (i.e. adjusted R2) ranged from 0.41 to 0.74, and the reconstructions performed well in a variety of verification tests. Additional analyses focused on stochastic estimation of drought frequency and return period, and detailed comparisons between reconstructed records and instrumental observations. Overall, this work points to the prevalence of severe, widespread drought in the UGRB. These analyses also highlight the relative wetness and lack of sustained dry periods during the instrumental period (1895-Present). Such long- term assessments are, in turn, vital tools as the Compact States contemplate the "Law of the River" in the face of climate change and ever-growing water demands.

  4. 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.

  5. Tree ring evidence for limited direct CO2 fertilization of forests over the 20th century

    Science.gov (United States)

    Gedalof, Ze'ev; Berg, Aaron A.

    2010-09-01

    The effect that rising atmospheric CO2 levels will have on forest productivity and water use efficiency remains uncertain, yet it has critical implications for future rates of carbon sequestration and forest distributions. Efforts to understand the effect that rising CO2 will have on forests are largely based on growth chamber studies of seedlings, and the relatively small number of FACE sites. Inferences from these studies are limited by their generally short durations, artificial growing conditions, unnatural step-increases in CO2 concentrations, and poor replication. Here we analyze the global record of annual radial tree growth, derived from the International Tree ring Data Bank (ITRDB), for evidence of increasing growth rates that cannot be explained by climatic change alone, and for evidence of decreasing sensitivity to drought. We find that approximately 20 percent of sites globally exhibit increasing trends in growth that cannot be attributed to climatic causes, nitrogen deposition, elevation, or latitude, which we attribute to a direct CO2 fertilization effect. No differences were found between species in their likelihood to exhibit growth increases attributable to CO2 fertilization, although Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa), the two most commonly sampled species in the ITRDB, exhibit a CO2 fertilization signal at frequencies very near their upper and lower confidence limits respectively. Overall these results suggest that CO2 fertilization of forests will not counteract emissions or slow warming in any substantial fashion, but do suggest that future forest dynamics may differ from those seen today depending on site conditions and individual species' responses to elevated CO2.

  6. Interactions of predominant insects and diseases with climate change in Douglas-fir forests of Western Oregon and Washington, USA

    Science.gov (United States)

    Forest disturbance regimes are beginning to show evidence of climate-mediated shifts associated with global climate change, and these patterns will likely continue due to continuing changes in environmental conditions. Tree growth is controlled by the physiological constraints o...

  7. Invasive scotch broom alters soil chemical properties in Douglas-fir forests of the Pacific Northwest, USA

    Science.gov (United States)

    Robert A. Slesak; Timothy B. Harrington; Anthony W. D′Amato

    2016-01-01

    Backgrounds and aims Scotch broom is an N-fixing invasive species that has high potential to alter soil properties. We compared soil from areas of Scotch broom invasion with nearby areas that had no evidence of invasion to assess the influence of broom on soil P fractions and other chemical properties. Methods The study was...

  8. 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-...

  9. BRANCH JUNCTIONS AND THE FLOW OF WATER THROUGH XYLEM IN DOUGLAS-FIR AND PONDEROSA PINE STEMS

    Science.gov (United States)

    Water flowing through the xylem of most plants from the roots to the leaves must pass through junctions where branches have developed from the main stem. These junctions have been studied as both flow constrictions and components of a hydraulic segmentation mechanism to protect ...

  10. Time to ignition is influenced by both moisture content and soluble carbohydrates in live Douglas fir and Lodgepole pine needles

    Science.gov (United States)

    Matt Jolly; Sara McAllister; Mark Finney; Ann Hadlow

    2010-01-01

    Living plants are often the primary fuels burning in wildland fire but little is known about the factors that govern their ignition behavior. Moisture content has long been hypothesized to determine the characteristics of fires spreading in live fuels but moisture content alone fails to explain observed differences in the ignition of various species at different times...

  11. Temporal change in soil carbon stability at a paired old-growth douglas-fir forest/clear-cut site

    Science.gov (United States)

    Forest ecosystems are estimated to contain one-half of the total terrestrial carbon (C) pool (1146 Pg), with two-thirds of this C (787 Pg) residing in forest soils. Given the magnitude of this C pool, it is critical to understand the effects of forest management practices on soil...

  12. Suitability of sphagnum moss, coir, and douglas fir bark as soilless substrates for container production of highbush blueberry

    Science.gov (United States)

    The purpose of the present study was to investigate the suitability of different soilless substrates for container production of highbush blueberry (Vaccinium sp.). Young plants of ‘Snowchaser’ blueberry were grown in 4.4-liter pots filled with media containing 10% perlite and varying proportions of...

  13. Cooperative advanced-generation breeding and testing of coastal Douglas-fir and western hemlock—strategy and implementation.

    Science.gov (United States)

    K. J.S. Jayawickrama; G.R. Johnson; T. Ye

    2005-01-01

    As in many temperate regions of the world, forest tree improvement got underway in the Pacific Northwest of the USA in the 1950s, with a number of companies and agencies starting independent tree improvement programs. Booth-Kelly Lumber Co., Crown Zellerbach Corp., the Industrial Forestry Association, Port Blakely Mill Co., Simpson Timber Co., Timber Service Co., the...

  14. Sudden oak death-caused changes to surface fuel loading and potential fire behavior in Douglas-fir-tanoak forests

    Science.gov (United States)

    Y.S. Valachovic; C.A. Lee; H. Scanlon; J.M. Varner; R. Glebocki; B.D. Graham; D.M. Rizzo

    2011-01-01

    We compared stand structure and fuel loading in northwestern California forests invaded by Phytophthora ramorum, the cause of sudden oak death, to assess whether the continued presence of this pathogen alters surface fuel loading and potential fire behavior in ways that may encumber future firefighting response. To attempt to account for these...

  15. Negligible impacts of biomass removal on Douglas-fir growth 29 years after outplanting in the northern Rocky Mountains

    Science.gov (United States)

    Woongsoon Jang; Christopher R. Keyes; Deborah S. Page-Dumroese

    2018-01-01

    To investigate the long-term impacts of biomass harvesting on site productivity, we remeasured trees in the 1974 Forest Residues Utilization Research and Development Program at Coram Experimental Forest in western Montana. Three levels (high, medium, and low) of biomass removal intensity combined with broadcast burning treatment were assigned after clearcut in western...

  16. Physiology and growth of redwood and Douglas-fir planted after variable density retention outside redwood’s range

    Science.gov (United States)

    Lucy Kerhoulas; Nicholas Kerhoulas; Wade Polda; John-Pascal Berrill

    2017-01-01

    Reforestation following timber harvests is an important topic throughout the coast redwood (Sequoia sempervirens (D. Don) Endl.) range. Furthermore, as drought-induced mortality spreads across many of California’s forests, it is important to understand how physiology and stand structure influence reforestation success. Finally, as climate...

  17. Will changes in phenology track climate change? A study of growth initiation timing in coast Douglas-fir

    Science.gov (United States)

    Kevin Ford; Connie Harrington; Sheel Bansal; Peter J. Gould; Brad St. Clair

    2016-01-01

    Under climate change, the reduction of frost risk, onset of warm temperatures and depletion of soil moisture are all likely to occur earlier in the year in many temperate regions. The resilience of tree species will depend on their ability to track these changes in climate with shifts in phenology that lead to earlier growth initiation in the spring. Exposure to warm...

  18. Disturbances and structural development of natural forest ecosystems with silvicultural implications, using Douglas-fir forests as an example.

    Science.gov (United States)

    J.F. Franklin; T.A. Spies; R.V. Pelt; A.B. Carey; D.A. Thornburgh; D.R. Berg; D.B. Lindenmayer; M.E. Harmon; W.S. Keeton; D.C. Shaw; K. Bible; J. Chen

    2002-01-01

    Forest managers need a comprehensive scientific understanding of natural stand development processes when designing silvicultural systems that integrate ecological and economic objectives, including a better appreciation of the nature of disturbance regimes and the biological legacies, such as live trees, snags, and logs, that they leave behind. Most conceptual forest...

  19. The timing of flowering in Douglas-fir is determined by cool-season temperatures and genetic variation

    Science.gov (United States)

    Janet S. Prevey; Constance A. Harrington; J. Bradley St. Clair

    2018-01-01

    Trees have evolved to time flowering to maximize outcrossing, minimize exposure to damaging frosts, and synchronize development with soil moisture and nutrient availability. Understanding the environmental cues that influence the timing of reproductive budburst will be important for predicting how flowering phenology of trees will change with a changing climate, and...

  20. Performance of full-sib families of Douglas-fir in pure-family and mixed-family deployments

    Science.gov (United States)

    Peter J. Gould; J. Bradley St.Clair; Paul D. Anderson

    2011-01-01

    A major objective of tree improvement programs is to identify genotypes that will perform well in operational deployments. Relatively little is known, however, about how the competitive environment affects performance in different types of deployments. We tested whether the genetic composition and density of deployments affect the performance of full-sib families of...

  1. Soil properties in old-growth Douglas-fir gaps in the western Cascade Mountains of Oregon

    Science.gov (United States)

    Robert P. Griffiths; Andrew N. Gray; Thomas A. Spies

    2010-01-01

    This study had three objectives: (1) to determine if there are correlations between aboveground vegetation and belowground soil properties within large 50-m-diameter gaps, (2) to determine how large gaps influence forest soils compared with nongap soils, and (3) to measure the effects of differently sized gaps on gap soils. Circular canopy gaps were created in old-...

  2. Species-specific and seasonal differences in chlorophyll fluorescence and photosynthetic light response among three evergreen species in a Madrean sky island mixed conifer forest

    Science.gov (United States)

    Potts, D. L.; Minor, R. L.; Braun, Z.; Barron-Gafford, G. A.

    2012-12-01

    Unlike the snowmelt-dominated hydroclimate of more northern mountainous regions, the hydroclimate of the Madrean sky islands is characterized by snowmelt and convective storms associated with the North American Monsoon. These mid-summer storms trigger biological activity and are important drivers of primary productivity. For example, at the highest elevations where mixed conifer forests occur, ecosystem carbon balance is influenced by monsoon rains. Whereas these storms' significance is increasingly recognized at the ecosystem scale, species-specific physiological responses to the monsoon are poorly known. Prior to and following monsoon onset, we measured pre-dawn and light-adapted chlorophyll fluorescence as well as photosynthetic light response in southwestern white pine (Pinus strobiformis), ponderosa pine (Pinus ponderosa), and Douglas fir (Pseudotsuga menziesii) in a Madrean sky island mixed conifer forest near Tucson, Arizona. Photochemical quenching (qp), an indicator of the proportion of open PSII reaction centers, was greatest in P. strobiformis and least in P. menziesii and increased in response to monsoon rains (repeated-measures ANOVA; species, F2,14 = 6.17, P = 0.012; time, F2,14= 8.17, P = 0.013). In contrast, non-photochemical quenching (qN), an indicator of heat dissipation ability, was greatest in P. ponderosa and least in P. menziesii, but was not influenced by monsoon onset (repeated-measures ANOVA; species, F2,12 = 4.18, P = 0.042). Estimated from leaf area-adjusted photosynthetic light response curves, maximum photosynthetic rate (Amax) was greatest in P. ponderosa and least in P. menziesii (repeated-measures ANOVA; species, F2,8= 40.8, P = 0.001). Surprisingly, while the monsoon positively influenced Amax among P. ponderosa and P. strobiformis, Amax of P. menziesii declined with monsoon onset (repeated-measures ANOVA; species x time, F2,8 = 13.8, P = 0.002). Calculated as the initial slope of the photosynthetic light response curve, light

  3. Preferences of Coptotermes formosanus Shiraki and Coptotermes gestroi (Wasmann (Blattodea: Rhinotermitidae among Three Commercial Wood Species

    Directory of Open Access Journals (Sweden)

    Nirmala K. Hapukotuwa

    2011-11-01

    Full Text Available The Formosan subterranean termite, Coptotermes formosanus Shiraki, and the Asian subterranean termite, Coptotermes gestroi (Wasmann, are both pests of wood in service in Hawaii and Florida. We conducted a laboratory study using method modified from those described in standard E1-09 of the American Wood Protection Association (AWPA 2009 to assess the termite resistance of three commercially available wood species used in regions of the USA where both termite species occur: Douglas fir, Pseudotsuga menziessii, southern yellow pine, Pinus spp. and redwood, Sequoia sempervirens. A multiple-choice (three-choice assay was used for four weeks (28 days in order to simulate field conditions of food choice and assess termite feeding preferences under 28 °C and 72–80% RH. 400 termites (360 workers: 40 soldiers were released into each test jar. Five replicates and two controls of each wood species were used with each termite species. Termite mortality was recorded at the end of the test; and wood wafers were oven-dried and weighed before and after termite exposure to determine the mass loss due to termite feeding, and rated visually on a 0 (failure to 10 (sound scale. There were significant differences in mean mass loss values among the three wood species and between two termite species. The mean mass loss value for redwood was significantly lower than Douglas fir and southern yellow pine with both termite species. However, C. formosanus showed increased feeding on Douglas fir and southern yellow pine compared to C. gestroi.

  4. Structural and compositional controls on transpiration in 40- and 450-year-old riparian forests in western Oregon, USA.

    Science.gov (United States)

    Moore, Georgianne W; Bond, Barbara J; Jones, Julia A; Phillips, Nathan; Meinzer, Federick C

    2004-05-01

    Large areas of forests in the Pacific Northwest are being transformed to younger forests, yet little is known about the impact this may have on hydrological cycles. Previous work suggests that old trees use less water per unit leaf area or sapwood area than young mature trees of the same species in similar environments. Do old forests, therefore, use less water than young mature forests in similar environments, or are there other structural or compositional components in the forests that compensate for tree-level differences? We investigated the impacts of tree age, species composition and sapwood basal area on stand-level transpiration in adjacent watersheds at the H.J. Andrews Forest in the western Cascades of Oregon, one containing a young, mature (about 40 years since disturbance) conifer forest and the other an old growth (about 450 years since disturbance) forest. Sap flow measurements were used to evaluate the degree to which differences in age and species composition affect water use. Stand sapwood basal area was evaluated based on a vegetation survey for species, basal area and sapwood basal area in the riparian area of two watersheds. A simple scaling exercise derived from estimated differences in water use as a result of differences in age, species composition and stand sapwood area was used to estimate transpiration from late June through October within the entire riparian area of these watersheds. Transpiration was higher in the young stand because of greater sap flux density (sap flow per unit sapwood area) by age class and species, and greater total stand sapwood area. During the measurement period, mean daily sap flux density was 2.30 times higher in young compared with old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees. Sap flux density was 1.41 times higher in young red alder (Alnus rubra Bong.) compared with young P. menziesii trees, and was 1.45 times higher in old P. menziesii compared with old western hemlock (Tsuga heterophylla (Raf

  5. Willamette Valley Ecoregion: Chapter 3 in Status and trends of land change in the Western United States--1973 to 2000

    Science.gov (United States)

    Wilson, Tamara S.; Sorenson, Daniel G.

    2012-01-01

    sedimentation and decreased water quality in the Willamette River and its tributary streams (Oregon Department of Fish and Wildlife, 2006). Recent years have seen a marked decline in forest health related to the increased frequency of multiyear droughts. Insect damage and other diseases also are present; however, drought- related water stress is the primary factor in coniferous-tree mortality (Oregon Department of Forestry, 2008). Trees most at risk include Douglas-fir (Pseudotsuga menziesii), grand fir (Abies grandis), and western red cedar (Thuja plicata). Overstocking by timber companies and planting on sites with poor conditions increase susceptibility. Over time, these problems may lead to changes in planting practices and the use of more drought-tolerant species such as ponderosa pine (Pinus ponderosa).

  6. Non-Linear Nitrogen Cycling and Ecosystem Calcium Depletion Along a Temperate Forest Soil Nitrogen Gradient

    Science.gov (United States)

    Sinkhorn, E. R.; Perakis, S. S.; Compton, J. E.; Cromack, K.; Bullen, T. D.

    2007-12-01

    Understanding how N availability influences base cation stores is critical for assessing long-term ecosystem sustainability. Indices of nitrogen (N) availability and the distribution of nutrients in plant biomass, soil, and soil water were examined across ten Douglas-fir (Pseudotsuga menziesii) stands spanning a three-fold soil N gradient (0-10 cm: 0.21 - 0.69% N, 0-100 cm: 9.2 - 28.8 Mg N ha-1) in the Oregon Coast Range. This gradient is largely the consequence of historical inputs from N2-fixing red alder stands that can add 100-200 kg N ha-1 yr-1 to the ecosystem for decades. Annual net N mineralization and litterfall N return displayed non-linear relationships with soil N, increasing initially, and then decreasing as N-richness increased. In contrast, nitrate leaching from deep soils increased linearly across the soil N gradient and ranged from 0.074 to 30 kg N ha-1 yr-1. Soil exchangeable Ca, Mg, and K pools to 1 m depth were negatively related to nitrate losses across sites. Ca was the only base cation exhibiting concentration decreases in both plant and soil pools across the soil N gradient, and a greater proportion of total available ecosystem Ca was sequestered in aboveground plant biomass at high N, low Ca sites. Our work supports a hierarchical model of coupled N-Ca cycles across gradients of soil N enrichment, with microbial production of mobile nitrate anions leading to depletion of readily available Ca at the ecosystem scale, and plant sequestration promoting Ca conservation as Ca supply diminishes. The preferential storage of Ca in aboveground biomass at high N and low Ca sites, while critical for sustaining plant productivity, may also predispose forests to Ca depletion in areas managed for intensive biomass removal. Long-term N enrichment of temperate forest soils appears capable of sustaining an open N cycle and key symptoms of N-saturation for multiple decades after the cessation of elevated N inputs.

  7. Current net ecosystem exchange of CO2 in a young mixed forest: any heritage from the previous ecosystem?

    Science.gov (United States)

    Violette, Aurélie; Heinesch, Bernard; Erpicum, Michel; Carnol, Monique; Aubinet, Marc; François, Louis

    2013-04-01

    For 15 years, networks of flux towers have been developed to determine accurate carbon balance with the eddy-covariance method and determine if forests are sink or source of carbon. However, for prediction of the evolution of carbon cycle and climate, major uncertainties remain on the ecosystem respiration (Reco, which includes the respiration of above ground part of trees, roots respiration and mineralization of the soil organic matter), the gross primary productivity (GPP) and their difference, the net ecosystem exchange (NEE) of forests. These uncertainties are consequences of spatial and inter-annual variability, driven by previous and current climatic conditions, as well as by the particular history of the site (management, diseases, etc.). In this study we focus on the carbon cycle in two mixed forests in the Belgian Ardennes. The first site, Vielsalm, is a mature stand mostly composed of beeches (Fagus sylvatica) and douglas fir (Pseudotsuga menziesii) from 80 to 100 years old. The second site, La Robinette, was covered before 1995 with spruces. After an important windfall and a clear cutting, the site was replanted, between 1995 and 2000, with spruces (Piceas abies) and deciduous species (mostly Betula pendula, Aulnus glutinosa and Salix aurita). The challenge here is to highlight how initial conditions can influence the current behavior of the carbon cycle in a growing stand compared to a mature one, where initial conditions are supposed to be forgotten. A modeling approach suits particularly well for sensitivity tests and estimation of the temporal lag between an event and the ecosystem response. We use the forest ecosystem model ASPECTS (Rasse et al., Ecological Modelling 141, 35-52, 2001). This model predicts long-term forest growth by calculating, over time, hourly NEE. It was developed and already validated on the Vielsalm forest. Modelling results are confronted to eddy-covariance data on both sites from 2006 to 2011. The main difference between both

  8. Low Tree-Growth Elasticity of Forest Biomass Indicated by an Individual-Based Model

    Directory of Open Access Journals (Sweden)

    Robbie A. Hember

    2018-01-01

    Full Text Available Environmental conditions and silviculture fundamentally alter the metabolism of individual trees and, therefore, need to be studied at that scale. However, changes in forest biomass density (Mg C ha−1 may be decoupled from changes in growth (kg C year−1 when the latter also accelerates the life cycle of trees and strains access to light, nutrients, and water. In this study, we refer to an individual-based model of forest biomass dynamics to constrain the magnitude of system feedbacks associated with ontogeny and competition and estimate the scaling relationship between changes in tree growth and forest biomass density. The model was driven by fitted equations of annual aboveground biomass growth (Gag, probability of recruitment (Pr, and probability of mortality (Pm parameterized against field observations of black spruce (Picea mariana (Mill. BSP, interior Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn. Franco, and western hemlock (Tsuga heterophylla (Raf. Sarg.. A hypothetical positive step-change in mean tree growth was imposed half way through the simulations and landscape-scale responses were then evaluated by comparing pre- and post-stimulus periods. Imposing a 100% increase in tree growth above calibrated predictions (i.e., contemporary rates only translated into 36% to 41% increases in forest biomass density. This corresponded with a tree-growth elasticity of forest biomass (εG,SB ranging from 0.33 to 0.55. The inelastic nature of stand biomass density was attributed to the dependence of mortality on intensity of competition and tree size, which decreased stand density by 353 to 495 trees ha−1, and decreased biomass residence time by 10 to 23 years. Values of εG,SB depended on the magnitude of the stimulus. For example, a retrospective scenario in which tree growth increased from 50% below contemporary rates up to contemporary rates indicated values of εG,SB ranging from 0.66 to 0.75. We conclude that: (1 effects of

  9. LATERAL ROOT DISTRIBUTION OF TREES IN AN OLD-GROWTH DOUGLAS-FIR FOREST INFERRED FROM UPTAKE OF TRACER 15N

    Science.gov (United States)

    Belowground competition for nutrients and water is considered a key factor affecting spatial organization and productivity of individual stems within forest stands, yet there are almost no data describing the lateral extent and overlap of competing root systems. We quantified th...

  10. Comparative analysis of Bacillus thuringiensis toxin binding to gypsy moth, browntail moth, and douglas-fir tussock moth midgut tissue sections using fluorescence microscopy

    Science.gov (United States)

    Algimantas P. Valaitis; John D. Podgwaite

    2011-01-01

    Many strains of Bacillus thuringiensis (Bt) produce insecticidal proteins, also referred to as Cry toxins, in crystal inclusions during sporulation. When ingested by insects, the Cry toxins bind to receptors on the brush border midgut epithelial cells and create pores in the epithelial gut membranes resulting in the death of...

  11. Dissolved carbon and nitrogen leaching following variable logging-debris retention and competing-vegetation control in Douglas-fir plantations of western Oregon and Washington

    Science.gov (United States)

    Robert A. Slesak; Stephen H. Schoenholtz; Timothy B. Harrington; Brian D. Strahm

    2009-01-01

    We examined the effect of logging-debris retention and competing-vegetation control (CCC, initial or annual applications) on dissolved organic carbon (DOC), dissolved organic nitrogen, and nitrate-N leaching to determine the relative potential of these practices to contribute to soil C and N loss at two contrasting sites. Annual CVC resulted in higher soil water...

  12. Using dendrometer and dendroclimatology data to predict the growth response of Douglas-fir to climate change in the Pacific Northwest, USA

    Science.gov (United States)

    Altered seasonal climate patterns towards hotter, drier summers through the 21st century resulting from global climate change could affect the growth of coniferous forests in the Pacific Northwest (PNW) region of North America. The seasonal effects of temperature, precipitation,...

  13. Identifying important spatial and temporal scales and patterns of soil properties in a tidal saltmarsh situated in a mixed red alder and Douglas fir watershed

    Science.gov (United States)

    Sea level rise is expected to drive a loss in salt marsh area and a change in marsh habitat composition, potentially leading to changes in the nitrogen source/sink dynamics of these systems. Estuaries in the Pacific Northwest might be particularly vulnerable to the effect of sal...

  14. Tree-ring analysis of the fungal disease Swiss needle cast and its impact on radial growth of Douglas-fir in the Western Oregon coast

    Science.gov (United States)

    To inform an individual-based forest stand model emphasizing belowground competition, we explored the potential of using the relative abundances of ribosomal PCR products from pooled and milled roots, to allocate total root biomass to each of the three coniferous species and to n...

  15. Modeling daily gas exchange of a Douglas-fir forest : comparison of three stomatal conductance models with and without a soil water stress function

    NARCIS (Netherlands)

    Wijk, van M.T.; Dekker, S.C.; Bouten, W.; Bosveld, F.C.; Kohsiek, W.; Kramer, K.; Mohren, G.M.J.

    2000-01-01

    Modeling stomatal conductance is a key element in predicting tree growth and water use at the stand scale. We compared three commonly used models of stomatal conductance, the Jarvis-Loustau, Ball-Berry and Leuning models, for their suitability for incorporating soil water stress into their

  16. Dynamics of spectral bio-indicators and their correlations with light use efficiency using directional observations at a Douglas-fir forest

    Science.gov (United States)

    Cheng, Yen-Ben; Middleton, Elizabeth M.; Hilker, Thomas; Coops, Nicholas C.; Black, T. Andrew; Krishnan, Praveena

    2009-09-01

    The carbon science community must rely on satellite remote sensing to obtain global estimates of photosynthetic activity, typically expressed as net primary production (NPP), gross primary production (GPP) or light use efficiency (LUE). The photochemical reflectance index (PRI), calculated as a normalized difference reflectance index using a physiologically active green band (~531 nm) and another physiologically insensitive green reference band (~570 nm), denoted as PRI(570), has been confirmed in many studies as being strongly related to LUE. Here, we examined the potential of utilizing PRI(570) observations under different illumination conditions for canopy LUE estimation of a forest. In order to evaluate this, directional hyperspectral reflectance measurements were collected continuously throughout the daytime periods using an automated spectroradiometer in conjunction with tower-based eddy covariance fluxes and environmental measurements at a coastal conifer forest in British Columbia, Canada throughout the 2006 growing season. A parameter calculated as the PRI(570) difference (dPRI(570)) between shaded versus sunlit canopy foliage sectors showed a strong correlation to tower-based LUE. The seasonal pattern for this correlation produced a dramatic change from high negative (r ~ -0.80) values in the springtime and early fall to high positive values (r ~ 0.80) during the summer months, which could represent the seasonality of physiological characteristics and environmental factors. Although the PRI(570) successfully tracked canopy LUE, one or both of its green bands (~531 and 570 nm) used to calculate the PRI are unavailable on most existing and planned near-term satellites. Therefore, we examined the potential to use 24 other spectral indexes for LUE monitoring that might be correlated to PRI, and thereby a substitute for it. We also continued our previous investigations into the influence of illumination conditions on the observed PRI(570) and other indexes. Among the 24 indexes examined, three PRI indexes using different reference bands (488, 551 and 705 nm) showed high correlations to the traditional PRI(570), especially PRI(551) and PRI(705). This indicates three additional PRI variations for LUE monitoring if the traditional reference band at 570 nm is not available but the 531 nm band is available. Five other indexes also yielded high correlations to PRI(570): Dmax and DM705, two indexes calculated from derivative reflectance spectra; a simple ratio of reflectance values at 685 nm and 655 nm (SR685_655); and a double-peak optical index (DPI). The diurnal and seasonal dynamics of these eight indexes and PRI(570) were explored. All of these indexes except DPI expressed linear dependence on available sunlight and more strongly expressed diurnal dynamics in April than in August during summer drought. The differences for shaded versus sunlit canopy foliage sectors were also calculated for the eight indexes, and their correlations to canopy LUE across the season were examined. The performances were similar for the most successful and seasonally stable indexes: dPRI(551), dPRI(705) and dPRI(570). The other five indexes showed good correlation to LUE in some but not all the months, and the months with high correlations varied among them.

  17. Dynamics of spectral bio-indicators and their correlations with light use efficiency using directional observations at a Douglas-fir forest

    International Nuclear Information System (INIS)

    Cheng, Yen-Ben; Middleton, Elizabeth M; Hilker, Thomas; Coops, Nicholas C; Black, T Andrew; Krishnan, Praveena

    2009-01-01

    The carbon science community must rely on satellite remote sensing to obtain global estimates of photosynthetic activity, typically expressed as net primary production (NPP), gross primary production (GPP) or light use efficiency (LUE). The photochemical reflectance index (PRI), calculated as a normalized difference reflectance index using a physiologically active green band (∼531 nm) and another physiologically insensitive green reference band (∼570 nm), denoted as PRI(570), has been confirmed in many studies as being strongly related to LUE. Here, we examined the potential of utilizing PRI(570) observations under different illumination conditions for canopy LUE estimation of a forest. In order to evaluate this, directional hyperspectral reflectance measurements were collected continuously throughout the daytime periods using an automated spectroradiometer in conjunction with tower-based eddy covariance fluxes and environmental measurements at a coastal conifer forest in British Columbia, Canada throughout the 2006 growing season. A parameter calculated as the PRI(570) difference (dPRI(570)) between shaded versus sunlit canopy foliage sectors showed a strong correlation to tower-based LUE. The seasonal pattern for this correlation produced a dramatic change from high negative (r ∼ −0.80) values in the springtime and early fall to high positive values (r ∼ 0.80) during the summer months, which could represent the seasonality of physiological characteristics and environmental factors. Although the PRI(570) successfully tracked canopy LUE, one or both of its green bands (∼531 and 570 nm) used to calculate the PRI are unavailable on most existing and planned near-term satellites. Therefore, we examined the potential to use 24 other spectral indexes for LUE monitoring that might be correlated to PRI, and thereby a substitute for it. We also continued our previous investigations into the influence of illumination conditions on the observed PRI(570) and other indexes. Among the 24 indexes examined, three PRI indexes using different reference bands (488, 551 and 705 nm) showed high correlations to the traditional PRI(570), especially PRI(551) and PRI(705). This indicates three additional PRI variations for LUE monitoring if the traditional reference band at 570 nm is not available but the 531 nm band is available. Five other indexes also yielded high correlations to PRI(570): Dmax and DM705, two indexes calculated from derivative reflectance spectra; a simple ratio of reflectance values at 685 nm and 655 nm (SR685 6 55); and a double-peak optical index (DPI). The diurnal and seasonal dynamics of these eight indexes and PRI(570) were explored. All of these indexes except DPI expressed linear dependence on available sunlight and more strongly expressed diurnal dynamics in April than in August during summer drought. The differences for shaded versus sunlit canopy foliage sectors were also calculated for the eight indexes, and their correlations to canopy LUE across the season were examined. The performances were similar for the most successful and seasonally stable indexes: dPRI(551), dPRI(705) and dPRI(570). The other five indexes showed good correlation to LUE in some but not all the months, and the months with high correlations varied among them

  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. ELEVATED TEMPERATURE, SOIL MOISTURE AND SEASONALITY BUT NOT CO2 AFFECT CANOPY ASSIMILATION AND SYSTEM RESPIRATION IN SEEDLING DOUGLAS-FIR ECOSYSTEMS

    Science.gov (United States)

    We investigated the effects of elevated atmospheric CO2 and air temperature on C cycling in trees and associated soil system, focusing on canopy CO2 assimilation (Asys) and system CO2 loss through respiration (Rsys). We hypothesized that both elevated CO2 and elevated temperature...

  20. DOES SOIL CO2 EFFLUX ACCLIMATIZETO ELEVATED TEMPERATURE AND CO2 DURING LONG-TERM TREATMENT OF DOUGLAS-FIR SEEDLINGS?

    Science.gov (United States)

    We investigated the effects of elevated soil temperature and atmospheric CO2 efflux (SCE) during the third an fourth years of study. We hypothesized that elevated temperature would stimulate SCE, and elevated CO2 would also stimulate SCE with the stimulation being greater at hig...

  1. Assessing the impact of current and projected climates on Douglas-fir productivity in British Columbia, Canada, using a process-based model (3-PG)

    International Nuclear Information System (INIS)

    Coops, N.C.; Hember, R.A.; Waring, R.H.

    2010-01-01

    Drained peat soils are significant sources of greenhouse gas (GHG) emissions, including nitrous oxide (N 2 O), methane (CH 4 ) and carbon dioxide (CO 2 ), which are produced in the soil and emitted year-round. This study measured N 2 O and CH 4 flux rates and total respiration over a 1-year period from a drained peatland with a grass field subsite and a forested subsite. Annual N 2 O respiration rates for the field were 660 mg per m 2 for the field and 297 mg per m 2 for the forest. Eighty per cent of the annual N 2 O emissions took place in the winter months. Higher emissions were detected during a thaw in April when accumulated N 2 O in the field was released. N 2 O emissions in the forest peaked when the top soil froze in January. Results of the study demonstrated that the timing of episodic high N 2 O emissions differs depending on land use. 52 refs., 1 tab., 6 figs.

  2. Effects of new export rules, a spotted owl plan, and recession on timber prices and shipments from the Douglas-fir region.

    Science.gov (United States)

    Donald F. Flora; Wendy J. McGInnls

    1992-01-01

    Several recently emplaced and potential Northwest timber policies are causing considerable market turbulence. Estimated were price and volume changes induced by three supply-side policies (a state-log export embargo, forest replanning, and spotted owl reservations) and the demand slide of 1990-91. Impacts were gauged separately and together by using a four-sector model...

  3. Effects of stand composition and thinning in mixed-species forests : a modeling approach applied to Douglas-fir and beech

    NARCIS (Netherlands)

    Bartelink, H.H.

    2000-01-01

    Models estimating growth and yield of forest stands provide important tools for forest management. Pure stands have been modeled extensively and successfully for decades; however, relatively few models for mixed-species stands have been developed. A spatially explicit, mechanistic model (COMMIX) is

  4. Site-to-site genetic correlations and their implications on breeding zone size and optimum number of progeny test sites for Coastal Douglas-fir.

    Science.gov (United States)

    G.R. Johnson

    1997-01-01

    Type B genetic correlations were used to examine the relation among geographic differences between sites and their site-to-site genetic (Type B) correlations. Examination of six local breeding zones in Oregon indicated that breeding zones were, for the most part, not too large because few environmental variables were correlated with Type B genetic correlations. The...

  5. Comparative effects of urea fertilizer and red alder in a site III, coast Douglas-fir plantation in the Washington Cascade Range.

    Science.gov (United States)

    Richard E. Miller; Harry W. Anderson; Marshall Murray; Rick. Leon

    2005-01-01

    Five randomly assigned treatments were used to quantify effects of adding varying numbers of red alder (Alnus rubra Bong.) or nitrogen (N) fertilization on growth of a 10-year-old conifer plantation at a medium quality site in the western Washington Cascade Range. Zero, 20, 40, and 80 alder trees per acre were retained along with about 300 conifers...

  6. Pulp quality from small-diameter trees.

    Science.gov (United States)

    G.C. Myers; S. Kumar; R.R. Gustafson; R.J. Barbour; S.M. Abubakr

    1997-01-01

    Kraft and thermomechanical (TMP) pulps were prepared and evaluated from lodgepole pine and mixed Douglas-fir/western larch sawmill residue chips; lodgepole pine, Douglas-fir, and western larch submerchantable logs; and lodgepole pine, Douglas-fir, and western larch small trees and tops. Kraft pulp from small trees and tops was identical to that from submerchantable...

  7. Historical effects of dissolved organic carbon export and land management decisions on the watershed-scale forest carbon budget of a coastal British Columbia Douglas-fir-dominated landscape.

    Science.gov (United States)

    Smiley, B P; Trofymow, J A

    2017-12-01

    To address how natural disturbance, forest harvest, and deforestation from reservoir creation affect landscape-level carbon (C) budgets, a retrospective C budget for the 8500 ha Sooke Lake Watershed (SLW) from 1911 to 2012 was developed using historical spatial inventory and disturbance data. To simulate forest C dynamics, data was input into a spatially-explicit version of the Carbon Budget Model-Canadian Forest Sector (CBM-CFS3). Transfers of terrestrial C to inland aquatic environments need to be considered to better capture the watershed scale C balance. Using dissolved organic C (DOC) and stream flow measurements from three SLW catchments, DOC load into the reservoir was derived for a 17-year period. C stocks and stock changes between a baseline and two alternative management scenarios were compared to understand the relative impact of successive reservoir expansions and sustained harvest activity over the 100-year period. Dissolved organic C flux for the three catchments ranged from 0.017 to 0.057 Mg C ha -1  year -1 . Constraining CBM-CFS3 to observed DOC loads required parameterization of humified soil C losses of 2.5, 5.5, and 6.5%. Scaled to the watershed and assuming none of the exported terrestrial DOC was respired to CO 2 , we hypothesize that over 100 years up to 30,657 Mg C may have been available for sequestration in sediment. By 2012, deforestation due to reservoir creation/expansion resulted in the watershed forest lands sequestering 14 Mg C ha -1 less than without reservoir expansion. Sustained harvest activity had a substantially greater impact, reducing forest C stores by 93 Mg C ha -1 by 2012. However approximately half of the C exported as merchantable wood during logging (~176,000 Mg C) may remain in harvested wood products, reducing the cumulative impact of forestry activity from 93 to 71 Mg C ha -1 . Dissolved organic C flux from temperate forest ecosystems is a small but persistent C flux which may have long term implications for C storage in inland aquatic systems. This is a first step integrating fluvial transport of C into a forest carbon model by parameterizing DOC flux from soil C pools. While deforestation related to successive reservoir expansions did impact the watershed-scale C budget, over multi-decadal time periods, sustained harvest activity was more influential.

  8. Historical effects of dissolved organic carbon export and land management decisions on the watershed-scale forest carbon budget of a coastal British Columbia Douglas-fir-dominated landscape

    Directory of Open Access Journals (Sweden)

    B. P. Smiley

    2017-07-01

    Full Text Available Abstract Background To address how natural disturbance, forest harvest, and deforestation from reservoir creation affect landscape-level carbon (C budgets, a retrospective C budget for the 8500 ha Sooke Lake Watershed (SLW from 1911 to 2012 was developed using historical spatial inventory and disturbance data. To simulate forest C dynamics, data was input into a spatially-explicit version of the Carbon Budget Model-Canadian Forest Sector (CBM-CFS3. Transfers of terrestrial C to inland aquatic environments need to be considered to better capture the watershed scale C balance. Using dissolved organic C (DOC and stream flow measurements from three SLW catchments, DOC load into the reservoir was derived for a 17-year period. C stocks and stock changes between a baseline and two alternative management scenarios were compared to understand the relative impact of successive reservoir expansions and sustained harvest activity over the 100-year period. Results Dissolved organic C flux for the three catchments ranged from 0.017 to 0.057 Mg C ha−1 year−1. Constraining CBM-CFS3 to observed DOC loads required parameterization of humified soil C losses of 2.5, 5.5, and 6.5%. Scaled to the watershed and assuming none of the exported terrestrial DOC was respired to CO2, we hypothesize that over 100 years up to 30,657 Mg C may have been available for sequestration in sediment. By 2012, deforestation due to reservoir creation/expansion resulted in the watershed forest lands sequestering 14 Mg C ha−1 less than without reservoir expansion. Sustained harvest activity had a substantially greater impact, reducing forest C stores by 93 Mg C ha−1 by 2012. However approximately half of the C exported as merchantable wood during logging (~176,000 Mg C may remain in harvested wood products, reducing the cumulative impact of forestry activity from 93 to 71 Mg C ha−1. Conclusions Dissolved organic C flux from temperate forest ecosystems is a small but persistent C flux which may have long term implications for C storage in inland aquatic systems. This is a first step integrating fluvial transport of C into a forest carbon model by parameterizing DOC flux from soil C pools. While deforestation related to successive reservoir expansions did impact the watershed-scale C budget, over multi-decadal time periods, sustained harvest activity was more influential.

  9. Steady as a rock: Biogeomorphic influence of nurse rocks and slope processes on kūpaoa (Dubautia menziesii) shrubs in Haleakalā Crater (Maui, Hawai'i)

    Science.gov (United States)

    Pérez, Francisco L.

    2017-10-01

    This study examines biogeomorphic interactions between nurse rocks, slope processes, and 300 kūpaoa (Dubautia menziesii) shrubs in Haleakalā Crater (Maui, Hawai'i). Research objectives were to: assess the association of kūpaoa with substrates upslope and downslope of plants, and proximity to the closest rock uphill; contrast shrub/substrate relationships with site frequency of sediment types; measure surface soil shear-strength and compressibility on 50 paired locations near boulders; and investigate the aggregation characteristics and spatial patterns of kūpaoa in relation to rock and substrate variation. Data analyzed came from three 100-plant surveys at 3 sites: a plant census at 2720-2975 m altitude, and wandering-quarter transects (WQTs) across two areas (2610-2710 m); ground sediment cover was estimated along four phototransects on these sites. Data for the three 100-plant surveys included substrate type-outcrops, blocks, cobbles, pebbles, exposed soil, organic litter-upslope from each plant, and distance to the largest rock upslope. The two surveys examined along WQTs included substrate type found downslope from kūpaoa, plant height, plant diameters across and along the slope, and distance between successively censused plants. Most plants grew downslope of nurse rocks; > 74% were adjacent to blocks or outcrops, and > 17% near cobbles. Plants showed avoidance for finer substrates; only 5.3% and 2.7% grew on/near bare soils and pebbles, respectively. About 92% of kūpaoa were ≤ 10 cm downslope of rocks; > 89% grew ≤ 2 cm away, and 83% in direct contact with a rock. Some seedlings also grew on pukiawe (Leptecophylla tameiameiae) nurse plants. Several stable rock microsites protected plants from disturbance by slope processes causing debris shift. Site sediments were significantly finer than substrates near plants; shrubs grew preferentially adjacent to boulders > 20 cm wide, which were more common near plants than across sites. Soils downslope of 50

  10. Horse Rock Ridge Research Natural Area: guidebook supplement 27.

    Science.gov (United States)

    Alan B. Curtis

    2003-01-01

    Horse Rock Ridge Research Natural Area (HRR RNA) was established in June 1995 to protect the best remaining example of a grassy “bald” (treeless area) on the western margin of the Cascade Range and its associated botanical, wildlife, and scenic values. This bald is surrounded by old-growth Pseudotsuga menziesii/Tsuga heterophylla...

  11. Dynamics of water transport and storage in conifers studied with deuterium and heat tracing techniques.

    Science.gov (United States)

    F.C. Meinzer; J.R. Brooks; J.-C. Domec; B.L. Gartner; J.M. Warren; D.R. Woodruff; K. Bible; D.C. Shaw

    2006-01-01

    The volume and complexity of their vascular systems make the dynamics of tong-distance water transport in large trees difficult to study. We used heat and deuterated water (D20) as tracers to characterize whole-tree water transport and storage properties in individual trees belonging to the coniferous species Pseudotsuga menziesii...

  12. Testing predictions of forest succession using long-term measurements: 100 yrs of observations in the Oregon Cascades

    Science.gov (United States)

    Mark E. Harmon; Robert J. Pabst

    2015-01-01

    Question: Many predictions about forest succession have been based on chronosequences. Are these predictions – at the population, community and ecosystemlevel – consistent with long-termmeasurements in permanent plots? Location: Pseudotsuga menziesii (Mirb.) Franco dominated forest in western Oregon, US.Methods: Over a 100-yr period,...

  13. Restoring dry and moist forests of the inland northwestern United States [Chapter 23

    Science.gov (United States)

    Theresa B. Jain; Russell T. Graham

    2015-01-01

    The complex topography of the Inland Northwestern United States (58.4 million ha) interacts with soils and a highly variable climate to provide a mosaic of dry and moist mixed conifer forest settings. Approximately 20% of the area is covered by dry forests dominated by Pinus ponderosa, Pseudotsuga menziesii and contains a diversity of lower vegetation ranging from a...

  14. Programmable calculator programs to solve softwood volume and value equations.

    Science.gov (United States)

    Janet K. Ayer. Sachet

    1982-01-01

    This paper presents product value and product volume equations as programs for handheld calculators. These tree equations are for inland Douglas-fir, young-growth Douglas-fir, western white pine, ponderosa pine, and western larch. Operating instructions and an example are included.

  15. Aerial surveys for Swiss needle cast in Western Oregon.

    Science.gov (United States)

    A. Kanaskie; M. McWilliams; J. Prukop; D. Overhulser; K. Sprengel

    2002-01-01

    In the last decade, Swiss needle cast (SNC), caused by the native fungus Phaeocryptopus gaeumannii, has severely damaged Douglas-fir in the Coast Range of western Oregon. The primary impact of the pathogen on Douglas-fir (the only susceptible tree species) is premature loss of foliage, which results in significant reduction in tree growth. Recent...

  16. SIMULTANEOUS ONE-TUBE QUANTIFICATION OF HOST AND PATHOGEN DNA WITH REAL-TIME POLYMERASE CHAIN REACTION

    Science.gov (United States)

    Phaeocryptopus gaeumannii is a widespread foliar parasite of Douglas-fir. Although normally innocuous, the fungus also causes the defoliating disease Swiss needle cast in heavily infected needles. The extent of P. gaeumannii colonization in Douglas-fir foliage was estimated wit...

  17. Phytotoxicity and weed control of oxyfluorfen and napropamide on container-grown conifer seedlings. Research memo No. 123

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    Factsheet assessing the affects of oxyfluorfen and napropamide applications on the designated crop plants and evaluating how well the herbicides controlled typical weed species. The study used recently-seeded Douglas-fir, white spruce and lodgepole pine and one-year-old Douglas-fir and white spruce. The oxyfluorfen formulation used was Goal and the napropamide formulation was Devrinol.

  18. Analysis of conifer forest regeneration using Landsat Thematic Mapper data

    Science.gov (United States)

    Fiorella, Maria; Ripple, William J.

    1995-01-01

    Landsat Thematic Mapper (TM) data were used to evaluate young conifer stands in the western Cascade Mountains of Oregon. Regression and correlation analyses were used to describe the relationships between TM band values and age of young Douglas-fir stands (2 to 35 years old). Spectral data from well regenerated Douglas-fir stands were compared to those of poorly regenerated conifer stands. TM bands 1, 2, 3, 5, 6, and 7 were inversely correlated with the age (r greater than or equal to -0.80) of well regenerated Douglas-fir stands. Overall, the 'structural index' (TM 4/5 ratio) had the highest correlation to age of Douglas-fir stands (r = 0.96). Poorly regenerated stands were spectrally distinct from well regenerated Douglas-fir stands after the stands reached an age of approximately 15 years.

  19. An Updated Review of Dendrochronological Investigations in Mexico, a Megadiverse Country with a High Potential for Tree-Ring Sciences

    Directory of Open Access Journals (Sweden)

    Andrea C. Acosta-Hernández

    2017-05-01

    Full Text Available Dendrochronology is a very useful science to reconstruct the long-term responses of trees and other woody plants forming annual rings in response to their environment. The present review considered Mexico, a megadiverse country with a high potential for tree-ring sciences given its high climatic and environmental variability. We reviewed papers considering Mexican tree species that were published from 2001 to 2016. Most of these studies examined tree species from temperate forests, mainly in the pine and fir species. The review included 31 tree species. The most intensively sampled family and species were the Pinaceae and Douglas fir (Pseudotsuga menziessi (Mirb. Franco, respectively. Some threatened tree species were also studied. Dendrochronological investigations were mainly conducted in northern and central Mexico, with Durango being the most sampled state. The reviewed studies were mostly developed for hydroclimatic reconstructions, which were mainly based on the tree-ring width as a proxy for the climate. Tree-ring studies were carried out in both national and foreign institutions. Our review identified relevant research gaps for dendrochronologists such as: (i biomes which are still scarcely studied (e.g., tropical dry forests and (ii approaches still rarely applied to Mexican forests as dendroecology.

  20. Responses of the lichen Ramalina menziesii Tayl. to ozone fumigations

    Science.gov (United States)

    J. Riddell; T.H. Nash; P. Padgett

    2010-01-01

    Tropospheric ozone (O3) is a strong oxidant, and is known to have serious negative effects on forest health. Lichens have bccn used as biomonitors of the effects of air pollution on forest health for sulfur and nitrogen pollutants. However, effects of O3 on lichens are not well understood, as past fumigation studies and...

  1. Especies forestales promisorias para la diversificación de forestaciones en la Patagonia Argentina

    OpenAIRE

    Godoy, María Marcela; Defossé, Guillermo E; Thren, Martin

    2007-01-01

    En el oeste de la Patagonia argentina existen aproximadamente 70 mil hectáreas forestadas, de las cuales el 80% corresponde a Pinus ponderosa y el resto a Pseudotsuga menziesii y Pinus contorta. Con el objetivo de evitar esta tendencia hacia los monocultivos con sus consecuencias ecológicas y sanitarias desfavorables, surge la necesidad de evaluar la posibilidad de cultivar otras especies forestales que permitan la diversificación de las actuales forestaciones. En este trabajo se analizaron p...

  2. Diagnóstico de la Planta de Lixiviación de la oficina Salitrera Santa Laura en Chile. Patrimonio de la Humanidad

    OpenAIRE

    Ortiz, R.; Jamet, A.; Moya, A.; González, M.; Varela, M. Paz; Hernández, M.; Fuentes, R.; Díaz, P.; Navarrete, J.

    2015-01-01

    La oficina salitrera Santa Laura, que es actualmente el lugar donde se mantiene la infraestructura industrial más completa del periodo del procesamiento del salitre, posee una Torre de Lixiviación que es considerada, por su singularidad, el ícono de la otrora industria salitrera en Chile. Esta impresionante estructura, construida casi en su totalidad con madera de Pino Oregón (Pseudotsuga menziesii) y elementos metálicos en sus uniones, sobrelleva desafortunadamente, después del cese del proc...

  3. Fate of nitrogenous fertilizers in forest soil

    International Nuclear Information System (INIS)

    Pang, P.C.K.

    1984-01-01

    The fate of the nitrogenous fertilizers through the processes of denitrification, ammonia volatilization, immobilization and uptake by a conifer is determined, with the aid of 15 N-labelled fertizers. The foliage of Douglas-fir was able to absorb gaseous ammonia under optimal conditions. Denitrification and immobilization of fertilizer-N by forest soil were highest with forest floor samples and decreased with depth. Laboratory studies with four-year-old Douglas-fir demostrated that a higher quantity of fertilizer-N was utilized by trees when the nitrogen was supplied as NO 3 - rather than NH 4 + . (M.A.C.) [pt

  4. Termite feeding preference to four wood species after gamma irradiation

    International Nuclear Information System (INIS)

    Katsumata, N.; Yoshimura, T.; Tsunoda, K.; Imamura, Y.

    2007-01-01

    The effect of gamma irradiation at 100 kGy and at lower levels on termite resistance was examined in the laboratory by no-choice and choice feeding termite tests (Coptotermes formosanus Shiraki) using four wood species: sapwood of Cryptomeria japonica D. Don, and heartwoods of Pseudotsuga menziesii (Mirbel) Franco, Larix kaempferi (Lambert) Carriere, and Chamaecyparis obtusa Endl. The wood consumption rates in C. japonica and P. menziesii specimens were likely to increase with increases in gamma-irradiation levels, whereas little effect of gamma irradiation was seen in L. kaempferi and C. obtusa. Similar results were obtained in the two-choice test. The current results indicated that in the two-choice test with C. formosanus, 100-kGy-irradiated C. japonica and P. menziesii, which are not rich in antitermite substances, were eaten more than other wood samples with or without gamma irradiation. However, only C. japonica showed significant difference in termite feeding activity. The mass loss in 100-kGy-irradiated C. japonica was significantly higher in the multichoice test

  5. A microanalytical method for the determination of dihydroquercetin in wood

    Science.gov (United States)

    Richard W. Hemingway; W.E. Hillis

    1969-01-01

    Dihydroquercetin (3,5,7,3',4'-pentahydroxyflavanone) is a major constituent of the alcohol soluble materials in the wood of Larch species and the wood and bark of Douglas-fir. A sensitive analytical method is needed to enable rapid assessment of amounts of dihydroquercetin (DHQ) when processing commercial materials and for studies of biochemical aspects of...

  6. The African Storybook and Language Teacher Identity in Digital Times

    Science.gov (United States)

    Stranger--Johannessen, Espen; Norton, Bonny

    2017-01-01

    The African Storybook (ASb) is a digital initiative that promotes multilingual literacy for African children by providing openly licenced children's stories in multiple African languages, as well as English, French, and Portuguese. Based on Darvin and Norton's (2015) model of identity and investment, and drawing on the Douglas Fir Group's (2016)…

  7. Drought-triggered western spruce budworm outbreaks in the Interior Pacific Northwest: A multi-century dendrochronological record

    Science.gov (United States)

    A. Flower; D. G. Gavin; E. K. Heyerdahl; R. A. Parsons; G. M. Cohn

    2014-01-01

    Douglas-fir forests in the interior Pacific Northwest are subject to sporadic outbreaks of the western spruce budworm, a species widely recognized as the most destructive defoliator in western North America. Outbreaks of the western spruce budworm often occur synchronously over broad regions and lead to widespread loss of leaf area and decrease in growth rates in...

  8. Can a fake fir tell the truth about Swiss needle cast?

    Science.gov (United States)

    A key question in dendrochronology to reconstruct forest disturbance history is how to distinguish between the effects of Swiss needle cast (SNC) and other forest disturbance agents (e.g., Douglas-fir beetle, tussock moth, western spruce budworm, laminated root rot, Armillaria ro...

  9. Advantages of a detailed pre-sale layout and logging plan.

    Science.gov (United States)

    Robert. Aufderheide

    1948-01-01

    During recent years the sale of timber from national forests in the Douglas-fir region has developed into big business. As the demand for stumpage steadily increases, and the allowable annual cut is approached or reached on a number of working circles, sale administration problems also increase and become more complex.

  10. Black bear damage to northwestern conifers in California: a review

    Science.gov (United States)

    Kenneth O. Fulgham; Dennis Hosack

    2017-01-01

    A total of 789 black bear damaged trees were investigate over a multi-year period on 14 different study sites chosen on lands of four participating timber companies. The sites ranged from 30 to 50 years of age. Four different conifer species were found to have black bear damage: coastal redwood (Sequoia sempervirens (D. Don) Endl.), Douglas-fir (...

  11. Seed fall and regeneration from a group selection cut . . . first year results

    Science.gov (United States)

    Philip M. McDonald

    1966-01-01

    To approximate a group selection cut at the Challenge Experimental Forest, 48 small openings of three sizes—30, 60, and 90 feet in diameter—were logged in 1963. One aim was to create conditions of light and soil moisture that would favor establishment and growth of Douglas-fir, sugar pine, and white fir over ponderosa pine. Seed fall and first-year...

  12. Using Scientific Information to Develop Management Strategies for Commercial Redwood Timberlands

    Science.gov (United States)

    Jeffrey C. Barrett

    2007-01-01

    In 1999, PALCO (Pacific Lumber Company), a private landowner, and the state and federal governments agreed to implement a unique Habitat Conservation Plan (HCP) on 89,000 hectares of commercial redwood and Douglas-fir timberlands in Humboldt County, California. The aquatics portion of the PALCO HCP contains a set of "interim" conservation strategies developed...

  13. Fire history and landscape dynamics in a late-successional reserve in the Klamath Mountains, California, USA

    Science.gov (United States)

    Alan H. Taylor; Carl N. Skinner

    1998-01-01

    The frequency, extent, and severity of fires strongly influence development patterns of forests dominated by Douglas-fir in the Pacific Northwest. Limited data on fire history and stand structure suggest that there is geographical variation in fire regimes and that this variation contributes to regional differences in stand and landscape structure. Managers need region...

  14. Evaluation of alternative mulches for blueberry over five production seasons

    Science.gov (United States)

    Highbush blueberry (Vaccinium corymbosum L.) is a calcifuge (acid-loving) plant that responds favorably to mulching with organic matter (OM). Until recently, most blueberry plantings in our region were grown with a mulch of douglas-fir sawdust, with additional nitrogen (N) fertilizer applied to comp...

  15. Laminated Root Rot of Western Conifers

    Science.gov (United States)

    E.E. Nelson; N.E. Martin; R.E. Williams

    1981-01-01

    Laminated root rot is caused by the native fungus Phellinus weirii (Murr.) Gilb. It occurs throughout the Northwestern United States and in southern British Columbia, Canada. The disease has also been reported in Japan and Manchuria. In the United States, the pathogen is most destructive in pure Douglas-fir stands west of the crest of the Cascade Range in Washington...

  16. 78 FR 14122 - Revocation of Permanent Variances

    Science.gov (United States)

    2013-03-04

    ... Douglas Fir planking had to have at least a 1,900 fiber stress and 1,900,000 modulus of elasticity, while the Yellow Pine planking had to have at least 2,500 fiber stress and 2,000,000 modulus of elasticity... the permanent variances, and affected employees, to submit written data, views, and arguments...

  17. Mechanism of waste biomass pyrolysis: Effect of physical and chemical pre-treatments

    International Nuclear Information System (INIS)

    Das, Oisik; Sarmah, Ajit K.

    2015-01-01

    To impart usability in waste based biomass through thermo-chemical reactions, several physical and chemical pre-treatments were conducted to gain an insight on their mode of action, effect on the chemistry and the change in thermal degradation profiles. Two different waste biomasses (Douglas fir, a softwood and hybrid poplar, a hardwood) were subjected to four different pre-treatments, namely, hot water pre-treatment, torrefaction, acid (sulphuric acid) and salt (ammonium phosphate) doping. Post pre-treatments, the changes in the biomass structure, chemistry, and thermal makeup were studied through electron microscopy, atomic absorption/ultra violet spectroscopy, ion exchange chromatography, and thermogravimetry. The pre-treatments significantly reduced the amounts of inorganic ash, extractives, metals, and hemicellulose from both the biomass samples. Furthermore, hot water and torrefaction pre-treatment caused mechanical disruption in biomass fibres leading to smaller particle sizes. Torrefaction of Douglas fir wood yielded more solid product than hybrid poplar. Finally, the salt pre-treatment increased the activation energies of the biomass samples (especially Douglas fir) to a great extent. Thus, salt pre-treatment was found to bestow thermal stability in the biomass. - Highlights: • Pre-treatments reduce ash, extractives, alkalines and hemicellulose from biomass. • Torrefaction of Douglas fir yields more solid product than hybrid poplar. • Salt pretreatment significantly increases the activation energy of biomass. • Acid and salt pretreatment bestows thermal stability in biomass.

  18. Fourmile Canyon Fire Findings

    Science.gov (United States)

    Russell Graham; Mark Finney; Chuck McHugh; Jack Cohen; Dave Calkin; Rick Stratton; Larry Bradshaw; Ned Nikolov

    2012-01-01

    The Fourmile Canyon Fire burned in the fall of 2010 in the Rocky Mountain Front Range adjacent to Boulder, Colorado. The fire occurred in steep, rugged terrain, primarily on privately owned mixed ponderosa pine and Douglas-fir forests. The fire started on September 6 when the humidity of the air was very dry (¡Ö

  19. Evaluation of recycled timber members

    Science.gov (United States)

    Douglas R. Rammer

    1999-01-01

    An experimental study was conducted to evaluate the residual shear capacity of large Douglas-fir timbers used in a military facility in Ardeen Hills, MN. A S-point and 4-point bending test was used to determine the effects of checks and splits on the shear strength capacity. Experimental results are compared to past shear and flexural studies.

  20. Feasibility of high-density climate reconstruction based on Forest Inventory and Analysis (FIA) collected tree-ring data

    Science.gov (United States)

    R. Justin DeRose; Shih-Yu Wang; John D. Shaw

    2013-01-01

    This study introduces a novel tree-ring dataset, with unparalleled spatial density, for use as a climate proxy. Ancillary Douglas fir and pinyon pine tree-ring data collected by the U.S. Forest Service Forest Inventory and Analysis Program (FIA data) were subjected to a series of tests to determine their feasibility as climate proxies. First, temporal coherence between...

  1. Investigating Forest Inventory and Analysis-collected tree-ring data from Utah as a proxy for historical climate

    Science.gov (United States)

    R. Justin DeRose; W. Shih-Yu (Simon) Wang; John D. Shaw

    2012-01-01

    Increment cores collected as part of the periodic inventory in the Intermountain West were examined for their potential to represent growth and be a proxy for climate (precipitation) over a large region (Utah). Standardized and crossdated time-series created from pinyon pine (n=249) and Douglas-fir (n=274) increment cores displayed spatiotemporal patterns in growth...

  2. Water stress, shoot growth and storage of non-structural carbohydrates along a tree height gradient in a tall conifer

    Science.gov (United States)

    David R. Woodruff; Frederick C. Meinzer

    2011-01-01

    We analyzed concentrations of starch, sucrose, glucose and fructose in upper branch wood, foliage and trunk sapwood of Douglas-fir trees in height classes ranging from ~2 to ~57 m. Mean concentrations of non-structural carbohydrates (NSC) for all tissues were highest in the tallest height class and lowest in the lowest height class, and height-related trends in NSC...

  3. Piloted ignition of live forest fuels

    Science.gov (United States)

    S. McAllister; I. Grenfell; A. Hadlow; W. M. Jolly; M. Finney; J. Cohen

    2012-01-01

    The most unpredictable and uncontrollable wildfires are those that burn in the crowns of live vegetation. The fuels that feed these crown fires are mostly live, green foliage. Unfortunately, little is known about how live fuels combust. To understand how live fuels burn, piloted ignition experiments were performed with lodgepole pine and Douglas-fir. The thermal...

  4. Nondestructive evaluation of potential quality of creosote-treated piles removed from service

    Science.gov (United States)

    Xiping. Wang; Robert J. Ross; John R. Erickson; John W. Forsman; Gary D. McGinnis; Rodney C. De Groot

    2001-01-01

    Stress-wave-based nondestructive evaluation methods were used to evaluate the potential quality and modulus of elasticity (MOE) of wood from creosote-treated Douglas-fir and southern pine piles removed from service. Stress-wave measurements were conducted on each pile section. Stress-wave propagation speeds were obtained to estimate the MOE of the wood. Tests were then...

  5. Nondestructive methods of evaluating quality of wood in preservative-treated piles

    Science.gov (United States)

    Xiping. Wang; Robert J. Ross; John R. Erickson; John W. Forsman; Gary D. McGinnis; Rodney C. De Groot

    2000-01-01

    Stress-wave-based nondestructive evaluation methods were used to evaluate the potential quality and modulus of elasticity (MOE) of wood in used preservative-treated Douglas-fir and southern pine piles. Stress wave measurements were conducted on each pile section. Stress wave propagation speeds in the piles were then obtained to estimate their MOE. This was followed by...

  6. Emissions from prescribed burning of timber slash piles in Oregon.

    Science.gov (United States)

    Emissions from burning piles of post-harvest timber slash (Douglas fir) in Grande Ronde, Oregon were sampled using an instrument platform lofted into the plume using a tether-controlled aerostat or balloon. Emissions of carbon monoxide, carbon dioxide, methane, particulate matte...

  7. Sampling methods for terrestrial amphibians and reptiles.

    Science.gov (United States)

    Paul Stephen Corn; R. Bruce. Bury

    1990-01-01

    Methods described for sampling amphibians and reptiles in Douglas-fir forests in the Pacific Northwest include pitfall trapping, time-constrained collecting, and surveys of coarse woody debris. The herpetofauna of this region differ in breeding and nonbreeding habitats and vagility, so that no single technique is sufficient for a community study. A combination of...

  8. Tree improvement in the Pacific Northwest.

    Science.gov (United States)

    R. Johnson

    2000-01-01

    Advanced-generation tree breeding programs are underway for Douglas-fir and coastal western hemlock. These programs will continue to improve growth rates and other traits. Regardless of whether seeds is from a seed orchard or natural collection, it must be used in its appropriated breeding zone or seed zone. These zones vary by species. Breeding programs are underway...

  9. Selected yield tables for plantations and natural stands in Inland Northwest Forests

    Science.gov (United States)

    Albert R. Stage; David L. Renner; Roger C. Chapman

    1988-01-01

    Yields arrayed by site index and age have been tabulated for plantations of 500 trees per acre, with five thinning regimes, for Douglas-fir, grand fir, and western larch. Yields were also tabulated for naturally regenerated stands of the grand fir-cedar-hemlock ecosystem of the Inland Empire. All yields were estimated with the Prognosis Model for Stand Development,...

  10. Opportunities for addressing laminated root rot caused by Phellinus sulphuracens in Washington's forests: A Report from the Washington State Academy of Sciences in cooperation with the Washington State Department of Natural Resources

    Science.gov (United States)

    R. James Cook; Robert L. Edmonds; Ned B. Klopfenstein; Willis Littke; Geral McDonald; Daniel Omdahl; Karen Ripley; Charles G. Shaw; Rona Sturrock; Paul Zambino

    2013-01-01

    This report from the Washington State Academy of Sciences (WSAS) is in response to a request from the Washington State Department of Natural Resources (DNR) to "identify approaches and opportunities ripe for research on understanding and managing root diseases of Douglas-fir." Similar to the process used by the National Research Council, the WSAS upon...

  11. Revisiting Pearson's climate and forest type studies on the Fort Valley Experimental Forest (P-53)

    Science.gov (United States)

    Joseph E. Crouse; Margaret M. Moore; Peter Z. Fule

    2008-01-01

    Five weather station sites were established in 1916 by Fort Valley personnel along an elevational gradient from the Experimental Station to near the top of the San Francisco Peaks to investigate the factors that controlled and limited forest types. The stations were located in the ponderosa pine, Douglas-fir, limber pine, Engelmann spruce, and Engelmann spruce/...

  12. Timing of slash burning with the seed crop—a case history.

    Science.gov (United States)

    Roy R. Silen

    1952-01-01

    Studies by Isaac indicate that regeneration to Douglas-fir following logging often fails because a good seed crop is destroyed in the slash fire. To prevent this loss during a good seed year, early burning before seed fall starts has been recommended. If early burning is too hazardous, only the concentrations of slash should be burned later in the fall. In contrast,...

  13. Sensitivity of TRIM projections to management, harvest, yield, and stocking adjustment assumptions.

    Science.gov (United States)

    Susan J. Alexander

    1991-01-01

    The Timber Resource Inventory Model (TRIM) was used to make several projections of forest industry timber supply for the Douglas-fir region. The sensitivity of these projections to assumptions about management and yields is discussed. A base run is compared to runs in which yields were altered, stocking adjustment was eliminated, harvest assumptions were changed, and...

  14. Changes in forest species composition and structure after stand-replacing wildfire in the mountains of southeastern Arizona

    Science.gov (United States)

    Ronald D. Quinn; Lin Wu

    2005-01-01

    A wildfire in the Chiricahua Mountains of southeastern Arizona apparently altered the long-term structure of the forest. The pre-fire canopy forest, which had not burned for 100 years, was an even mixture of Arizona pines and Rocky Mountain Douglas-firs. A decade later the new forest was numerically dominated by quaking aspen seedlings in clumps separated by persistent...

  15. N2-fixing red alder indirectly accelerates ecosystem nitrogen cycling

    Science.gov (United States)

    Perakis, Steven S.; Matkins, Joselin J.; Hibbs, David E.

    2012-01-01

    Symbiotic N2-fixing tree species can accelerate ecosystem N dynamics through decomposition via direct pathways by producing readily decomposed leaf litter and increasing N supply to decomposers, as well as via indirect pathways by increasing tissue and detrital N in non-fixing vegetation. To evaluate the relative importance of these pathways, we compared three-year decomposition and N dynamics of N2-fixing red alder leaf litter (2.34 %N) to both low-N (0.68 %N) and high-N (1.21 %N) litter of non-fixing Douglas-fir, and decomposed each litter source in four forests dominated by either red alder or Douglas-fir. We also used experimental N fertilization of decomposition plots to assess elevated N availability as a potential mechanism of N2-fixer effects on litter mass loss and N dynamics. Direct effects of N2-fixing red alder on decomposition occurred primarily as faster N release from red alder than Douglas-fir litter, but direct increases in N supply to decomposers via fertilization did not stimulate decomposition of any litter. Fixed N indirectly influenced detrital dynamics by increasing Douglas-fir tissue and litter N concentrations, which accelerated litter N release without accelerating mass loss. By increasing soil N, tissue N, and the rate of N release from litter of non-fixers, we conclude that N2-fixing vegetation can indirectly foster plant-soil feedbacks that contribute to the persistence of elevated N availability in terrestrial ecosystems.

  16. Kraft pulping of industrial wood waste

    Science.gov (United States)

    Aziz. Ahmed; Masood. Akhtar; Gary C. Myers; Gary M. Scott

    1998-01-01

    Most of the approximately 25 to 30 million tons of industrial wood waste generated in the United States per year is burned for energy and/or landfilled. In this study, kraft pulp from industrial wood waste was evaluated and compared with softwood (loblolly pine, Douglas-fir) and hardwood (aspen) pulp. Pulp bleachability was also evaluated. Compared to loblolly pine...

  17. Effects of forest harvest on stream-water quality and nitrogen cycling in the Caspar Creek watershed

    Science.gov (United States)

    Randy A. Dahlgren

    1998-01-01

    The effects of forest harvest on stream-water quality and nitrogen cycling were examined for a redwood/Douglas-fir ecosystem in the North Fork, Caspar Creek experimental watershed in northern California. Stream-water samples were collected from treated (e.g., clearcut) and reference (e.g., noncut) watersheds, and from various locations downstream from the treated...

  18. Dwarf mistletoe and host tree interactions in managed forests of the Pacific Northwest.

    Science.gov (United States)

    Donald M. Knutson; Robert. Tinnin

    1980-01-01

    Dwarf mistletoes in the Pacific Northwest infect true firs, larch, pine, Douglas-fir, and hemlock. Forty-one percent of all stands east of the crest of the Cascade Range and 10 percent of west-side stands are infected. General characteristics of dwarf mistletoe are discussed including mortality and growth losses rate of spread within a tree and within stands. Relation...

  19. Investigation of biomasses and chars obtained from pyrolysis of different biomasses with solid-state 13C and 23Na nuclear magnetic resonance spectroscopy

    NARCIS (Netherlands)

    Link, S.; Arvelakis, S.; Spliethoff, H.; Waard, de P.; Samoson, A.

    2008-01-01

    A number of biomass samples (reed, pine pellets, Douglas fir wood chips, wheat straw, peach stones, and olive residue), pretreated biomass samples (leached wheat straw, leached peach stones, and leached olive residue), as well as their chars obtained by pyrolysis using different heating rates (5,

  20. Minimizing and predicting delamination of southern plywood in exterior exposure

    Science.gov (United States)

    Peter Koch

    1967-01-01

    Southern pine plywood is substantially all being manufactured with phenolic glue for exterior use. Because panels must not delaminate in service, a reliable predictor of glueline durability is required. Drawing on the experience of the Douglas-fir plywood industry, southern manufacutrers have adopted as a predictor the percentage of wood failure(% WF) observed in...

  1. Modelling trends in soil solution concentrations under five forest-soil combinations in the Netherlands

    NARCIS (Netherlands)

    Salm, van der C.; Vries, de W.; Kros, J.

    1996-01-01

    The influence of forest and soil properties on changes in soil solution concentration upon a reduction deposition was examined for five forest-soil combinations with the dynamic RESAM model. Predicted concentrations decreased in the direction Douglas fir - Scotch pine - oak, due to decreased

  2. Production rates and costs of cable yarding wood residue from clearcut units

    Science.gov (United States)

    Chris B. LeDoux

    1984-01-01

    Wood residue is a little used source of fiber, chips, and fuel because harvest costs are largely unknown. This study calculates incremental production rates and costs for yarding and loading logging residue in clearcut old-growth Douglas-fir/western hemlock forests. Harvest operations were observed for two timber sales in western Oregon. Three different cable yarding...

  3. An analysis of production and costs in high-lead yarding.

    Science.gov (United States)

    Magnus E. Tennas; Robert H. Ruth; Carl M. Berntsen

    1955-01-01

    In recent years loggers and timber owners have needed better information for estimating logging costs in the Douglas-fir region. Brandstrom's comprehensive study, published in 1933 (1), has long been used as a guide in making cost estimates. But the use of new equipment and techniques and an overall increase in logging costs have made it increasingly difficult to...

  4. FEM growth and yield data monocultures - White willow

    NARCIS (Netherlands)

    Jansen, J.J.; Oosterbaan, A.; Goudzwaard, L.; Oldenburger, J.F.; Mohren, G.M.J.; Ouden, den J.

    2016-01-01

    The current database is part of the FEM growth and yield database, a collection of growth and yield data from even-aged monocultures (douglas fir, common oak, poplar, Japanese Larch, Norway spruce, Scots pine, Corsican pine, Austrian pine, red oak and several other species, with only a few plots,

  5. FEM growth and yield data Monocultures - Poplar (revised version)

    NARCIS (Netherlands)

    Mohren, G.M.J.; Goudzwaard, L.; Jansen, J.J.; Schmidt, P.; Oosterbaan, A.; Oldenburger, J.; Ouden, den J.

    2017-01-01

    The current database is part of the FEM growth and yield database, a collection of growth and yield data from even-aged monocultures (douglas fir, common oak, poplar, Japanese Larch, Norway spruce, Scots pine, Corsican pine, Austrian pine, red oak and several other species with only a few plots,

  6. FEM growth and yield data monocultures - Poplar

    NARCIS (Netherlands)

    Mohren, G.M.J.; Goudzwaard, L.; Jansen, J.J.; Oosterbaan, A.; Oldenburger, J.F.; Ouden, den J.

    2016-01-01

    The current database is part of the FEM growth and yield database, a collection of growth and yield data from even-aged monocultures (douglas fir, common oak, poplar, Japanese Larch, Norway spruce, Scots pine, Corsican pine, Austrian pine, red oak and several other species, with only a few plots,

  7. First report of Phytophthora ramorum infecting mistletoe in California

    Science.gov (United States)

    K.L. Riley; G.A. Chastagner

    2011-01-01

    In 2005 and 2006, white fir and Douglas-fir growing in a Christmas tree plantation near Los Gatos, CA, under a black walnut tree infected with mistletoe tested positive for Phytophthora ramorum, the cause of Sudden Oak Death. Isolation from a symptomatic mistletoe inflorescence stalk was positive for P. ramorum. In 2007,...

  8. Effects of green-tree retention on abundance and guild composition of corticolous arthropods

    Science.gov (United States)

    Juraj Halaj; Charles B. Halpern; Hoonbok Yi

    2009-01-01

    We studied the effects of varying levels and patterns of green-tree retention on the community composition of bark-dwelling arthropods. Arthropods were sampled with crawl traps installed on 280 live trees and 260 snags (all Douglas-fir) at three locations (experimental blocks) in the western Cascade Range of Oregon and Washington. Sampling coincided with the breeding...

  9. Mechanism of waste biomass pyrolysis: Effect of physical and chemical pre-treatments

    Energy Technology Data Exchange (ETDEWEB)

    Das, Oisik [Department of Biological Systems Engineering, Washington State University, Pullman 99164-6120, WA (United States); Department of Civil and Environmental Engineering, University of Auckland, Auckland 1142 (New Zealand); Sarmah, Ajit K., E-mail: a.sarmah@auckland.ac.nz [Department of Civil and Environmental Engineering, University of Auckland, Auckland 1142 (New Zealand)

    2015-12-15

    To impart usability in waste based biomass through thermo-chemical reactions, several physical and chemical pre-treatments were conducted to gain an insight on their mode of action, effect on the chemistry and the change in thermal degradation profiles. Two different waste biomasses (Douglas fir, a softwood and hybrid poplar, a hardwood) were subjected to four different pre-treatments, namely, hot water pre-treatment, torrefaction, acid (sulphuric acid) and salt (ammonium phosphate) doping. Post pre-treatments, the changes in the biomass structure, chemistry, and thermal makeup were studied through electron microscopy, atomic absorption/ultra violet spectroscopy, ion exchange chromatography, and thermogravimetry. The pre-treatments significantly reduced the amounts of inorganic ash, extractives, metals, and hemicellulose from both the biomass samples. Furthermore, hot water and torrefaction pre-treatment caused mechanical disruption in biomass fibres leading to smaller particle sizes. Torrefaction of Douglas fir wood yielded more solid product than hybrid poplar. Finally, the salt pre-treatment increased the activation energies of the biomass samples (especially Douglas fir) to a great extent. Thus, salt pre-treatment was found to bestow thermal stability in the biomass. - Highlights: • Pre-treatments reduce ash, extractives, alkalines and hemicellulose from biomass. • Torrefaction of Douglas fir yields more solid product than hybrid poplar. • Salt pretreatment significantly increases the activation energy of biomass. • Acid and salt pretreatment bestows thermal stability in biomass.

  10. Resistance of borax–copper treated wood in aboveground exposure to attack by Formosan subterranean termites

    Science.gov (United States)

    Stan Lebow; Bessie Woodward; Douglas Crawford; William Abbott

    2005-01-01

    The spread of Formosan subterranean termites (FSTs) in the southern United States has increased public interest in finding a preservative treatment to protect framing lumber from termite attack. This study evaluated the use of a borax-based preservative to protect wood from FST attack. Southern Pine and Douglas-fir specimens were pressure-treated with three...

  11. A MIXED MODEL ANALYSIS OF SOIL CO2 EFFLUX AND NIGHT-TIME RESPIRATION RESPONSES TO ELEVATED CO2 AND TEMPERATURE

    Science.gov (United States)

    Abstract: We investigated the effects of elevated soil temperature and atmospheric CO2 on soil CO2 efflux and system respiration responses. The study was conducted in sun-lit controlled-environment chambers using two-year-old Douglas-fir seedlings grown in reconstructed litter-so...

  12. Forest research notes, Pacific Northwest Forest Experiment Station, No. 23, November 27, 1937.

    Science.gov (United States)

    J. Elton Lodewick; P.A. Briegleb; F.L. Moravets; Leo A. Isaac; William G. Morris; Wade. DeVries

    1937-01-01

    Douglas fir, the most abundant and most used lumber species in the forests of the Pacific Northwest, is being pulped on a commercial scale by the sulfate and soda processes. The markets for unbleached pulps are limited, and there has been much speculation as to the possibilities of developing pulping processes whereby the enormous quantities of otherwise unutilized...

  13. Turbulence considerations for comparing ecosystem exchange over old-growth and clear-cut stands for limited fetch and complex canopy flow conditions

    Science.gov (United States)

    Sonia Wharton; Matt Schroeder; Kyaw Tha Paw U; Matthias Falk; Ken Bible

    2009-01-01

    Carbon dioxide (CO2), water vapor, and energy fluxes were measured using eddy covariance (EC) methodology over three adjacent evergreen forests in southern Washington State to identify stand-level age-effects on ecosystem exchange. The sites represent Douglas-fir forest ecosystems at two contrasting successional stages: old-growth (OG) and early...

  14. Vertical stratification of soil water storage and release dynamics in Pacific Northwest coniferous forests.

    Science.gov (United States)

    J.M. Warren; F.C. Meinzer; J.R. Brooks; J.C. Domec

    2005-01-01

    We characterized vertical variation in the seasonal release of stored soil moisture in old-growth ponderosa pine (OG-PP, xeric), and young and old-growth Douglas-fir (Y-DF, OG-DF, mesic) forests to evaluate changes in water availability for root uptake. Soil water potential (ψ) and volumetric water content (θ...

  15. Timber value—a matter of choice: a study of how end use assumptions affect timber values.

    Science.gov (United States)

    John H. Beuter

    1971-01-01

    The relationship between estimated timber values and actual timber prices is discussed. Timber values are related to how, where, and when the timber is used. An analysis demonstrates the relative values of a typical Douglas-fir stand under assumptions about timber use.

  16. Ectomycorrhizal mats alter forest soil biogeochemistry

    Science.gov (United States)

    Laurel A. Kluber; Kathryn M. Tinnesand; Bruce A. Caldwell; Susie M. Dunham; Rockie R. Yarwood; Peter J. Bottomley; David D. Myrold

    2010-01-01

    Dense hyphal mats formed by ectomycorrhizal (EcM) fungi are prominent features in Douglas-fir forest ecosystems, and have been estimated to cover up to 40% of the soil surface in some forest stands. Two morphotypes of EcM mats have been previously described: rhizomorphic mats, which have thick hyphal rhizomorphs and are found primarily in the organic horizon, and...

  17. Distinctive fungal and bacterial communities are associated with mats formed by ectomycorrhizal fungi

    Science.gov (United States)

    Laurel A. Kluber; Jane E. Smith; David D. Myrold

    2011-01-01

    The distinct rhizomorphic mats formed by ectomycorrhizal Piloderma fungi are common features of the organic soil horizons of coniferous forests of the Pacific Northwest. These mats have been found to cover 25-40% of the forest floor in some Douglas-fir stands, and are associated with physical and biochemical properties that distinguish them from...

  18. Estimating tree bole and log weights from green densities measured with the Bergstrom Xylodensimeter.

    Science.gov (United States)

    Dale R. Waddell; Michael B. Lambert; W.Y. Pong

    1984-01-01

    The performance of the Bergstrom xylodensimeter, designed to measure the green density of wood, was investigated and compared with a technique that derived green densities from wood disk samples. In addition, log and bole weights of old-growth Douglas-fir and western hemlock were calculated by various formulas and compared with lifted weights measured with a load cell...

  19. Operations Research techniques in the management of large-scale reforestation programs

    Science.gov (United States)

    Joseph Buongiorno; D.E. Teeguarden

    1978-01-01

    A reforestation planning system for the Douglas-fir region of the Western United States is described. Part of the system is a simulation model to predict plantation growth and to determine economic thinning regimes and rotation ages as a function of site characteristics, initial density, reforestation costs, and management constraints. A second model estimates the...

  20. Nutritional hotspots and the secret life of forests

    Science.gov (United States)

    Jane Smith; Laurel Kluber; Noreen Parks

    2014-01-01

    The floor of a Douglas-fir forest may be rich in organic matter, but nutrients essential to plant growth are locked within the decomposing needles, leaves, and fallen wood. Before nitrogen, phosphorus, and other nutrients can be cycled back through the forest system, they need to be further broken down into forms accessible to plants. Understanding how nutrients become...

  1. How can we increase the production, quality and health of our forests by selective breeding

    Energy Technology Data Exchange (ETDEWEB)

    Nanson, A

    1981-01-01

    Selective breeding programmes in Belgium are discussed, and a number of seed plantations are listed. Descriptions are given of the performance of European provenances of spruce and larch and American and Canadian Douglas fir, at 3 plantations in Belgium. An account is given of Belgian success in breeding varieties of spruce with late-opening buds resistant to late frosts. (Refs. 8).

  2. 77 FR 19177 - Beaverhead-Deerlodge National Forest, Jefferson Ranger District, Montana, Boulder River Salvage...

    Science.gov (United States)

    2012-03-30

    ... statement. SUMMARY: The project proposes to salvage by clearcut harvest dead and lodgepole pine infested or... Need for Action The purpose and need for this project is to harvest merchantable wood products from..., before the value of the wood deteriorates; reduce stand density in lodgepole pine and Douglas-fir stands...

  3. Relationship between stress wave velocities of green and dry veneer

    Science.gov (United States)

    Brian K. Brashaw; Xiping Wang; Robert J. Ross; Roy F. Pellerin

    2004-01-01

    This paper evaluates the relationship between the stress wave velocities of green and dry southern pine and Douglas-fir veneers. A commercial stress wave timer and a laboratory signal analysis system were used to measure the transit time required for an induced stress wave to travel the longitudinal length of each veneer. Stress wave transit times were measured in the...

  4. FEM growth and yield data monocultures - other species

    NARCIS (Netherlands)

    Goudzwaard, L.; Jansen, J.J.; Oosterbaan, A.; Oldenburger, J.F.; Mohren, G.M.J.; Ouden, den J.

    2016-01-01

    The current database is part of the FEM growth and yield database, a collection of growth and yield data from even-aged monocultures (douglas fir, common oak, poplar, Japanese Larch, Norway spruce, Scots pine, Corsican pine, Austrian pine, red oak and several other species, with only a few plots,

  5. Climate drivers of regionally synchronous fires in the inland northwest (1651-1900)

    Science.gov (United States)

    Emily K. Heyerdahl; Donald McKenzie; Lori D. Daniels; Amy E. Hessl; Jeremy S. Littell; Nathan J. Mantua

    2008-01-01

    We inferred climate drivers of regionally synchronous surface fires from 1651 to 1900 at 15 sites with existing annually accurate fire-scar chronologies from forests dominated by ponderosa pine or Douglas-fir in the inland Northwest (interior Oregon,Washington and southern British Columbia).Years with widespread fires (35 years with fire at 7 to 11 sites) had warm...

  6. New application of two Antarctic macroalgae Palmaria decipiens and Desmarestia menziesii in the synthesis of gold and silver nanoparticles

    Science.gov (United States)

    González-Ballesteros, N.; González-Rodríguez, J. B.; Rodríguez-Argüelles, M. C.; Lastra, M.

    2018-03-01

    In this study, two Antarctic macroalgae (Rhodophyta Palmaria decipiens and Phaeophyta Desmarestia menziessi) were selected in order to report their use for the biosynthesis of nanomaterials. Two aqueous extracts of the macroalgae were prepared and their reducing activity, total phenolic content and DPPH scavenging activity were determined, showing that brown seaweed has higher antioxidant activity than red seaweed. Aqueous extracts were used as an eco-friendly, one-pot synthetic route to obtain gold and silver nanoparticles acting both as reducing and stabilizing agents. The nanoparticles obtained were characterized by UV-Vis spectroscopy and Transmission electron microscopy (TEM), demonstrating the formation of gold and silver nanoparticles with mean diameters of 36.8 ± 5.3 and 11.5 ± 3.3 nm for Au@PD and Au@DM and 7.0 ± 1.2 nm and 17.8 ± 2.6 nm in the case of Ag@PD and Ag@DM. Lastly, functional groups of the biomolecules present in the extracts were characterized by Fourier transform infrared spectra (FTIR) prior to, and after, the synthesis of the nanoparticles, in order to obtain information about the biomolecules involved in the reducing and stabilization process.

  7. Effects of past logging and grazing on understory plant communities in a montane Colorado forest

    Science.gov (United States)

    Fornwalt, P.J.; Kaufmann, M.R.; Huckaby, L.S.; Stohlgren, T.J.

    2009-01-01

    Throughout Pinus ponderosa-Pseudotsuga menziesii forests of the southern Colorado Front Range, USA, intense logging and domestic grazing began at the time of Euro-American settlement in the late 1800s and continued until the early 1900s. We investigated the long-term impacts of these settlement-era activities on understory plant communities by comparing understory composition at a historically logged and grazed site to that of an environmentally similar site which was protected from past use. We found that species richness and cover within functional groups rarely differed between sites in either upland or riparian areas. Multivariate analyses revealed little difference in species composition between sites on uplands, though compositional differences were apparent in riparian zones. Our findings suggest that settlement-era logging and grazing have had only minor long-term impacts on understories of upland Front Range P. ponderosa-P. menziesii forests, though they have had a greater long-term influence on riparian understories, where these activities were likely the most intense. ?? 2008 Springer Science+Business Media B.V.

  8. Tree host range and world distribution of the extomycorrhizal fungus Pisolithus tinctorius.

    Science.gov (United States)

    Marx, D H

    1977-03-01

    The natural occurrence of Pisolithus tinctorius has been confirmed in 33 countries of the world and in 38 states in the United States. This ectomycorrhizal fungus is found associated with various tree species in nurseries, urban areas, orchards, forests, and strip-mined spoils. Experiments have proved that this fungal symbiont forms ectomycorrhizae with Abies procera, Betula pendula, Carya illnoensis, 11 species of Eucalyptus, 30 species of Pinus, Pseudotsuga menziesii var. meniziesii, 2 species of Quercus, and Tsuga heterophylla. Pisolithus has also been reported growing under natural conditions in association with three additional species of Betula, two species of Eucalyptus, nine species of Pinus, and eight species of Quercus, Populus tremuloides, Pseudotsuga grandidenta, and Salix humilis. This fungal symbiont has great potential in forestation efforts because of (1) the availability of practical techniques for artificially introducing in into nursery soils; (2) its ability to improve tree survival and growth in the nursery and the field; (3) its near worldwide distribution on a variety of sites; and (4) its broad host range encompassing many of the world's most important tree species.

  9. Advanced Blade Manufacturing Project - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    POORE, ROBERT Z.

    1999-08-01

    The original scope of the project was to research improvements to the processes and materials used in the manufacture of wood-epoxy blades, conduct tests to qualify any new material or processes for use in blade design and subsequently build and test six blades using the improved processes and materials. In particular, ABM was interested in reducing blade cost and improving quality. In addition, ABM needed to find a replacement material for the mature Douglas fir used in the manufacturing process. The use of mature Douglas fir is commercially unacceptable because of its limited supply and environmental concerns associated with the use of mature timber. Unfortunately, the bankruptcy of FloWind in June 1997 and a dramatic reduction in AWT sales made it impossible for ABM to complete the full scope of work. However, sufficient research and testing were completed to identify several promising changes in the blade manufacturing process and develop a preliminary design incorporating these changes.

  10. Survival and development of Lymantria monacha (Lepidoptera: Lymantriidae) on North American and introduced Eurasian tree species.

    Science.gov (United States)

    Keena, M A

    2003-02-01

    Lymantria monacha (L.) (Lepidoptera: Lymantriidae), the nun moth, is a Eurasian pest of conifers that has potential for accidental introduction into North America. To project the potential host range of this insect if introduced into North America, survival and development of L. monacha on 26 North American and eight introduced Eurasian tree species were examined. Seven conifer species (Abies concolor, Picea abies, P. glauca, P. pungens, Pinus sylvestris with male cones, P. menziesii variety glance, and Tsuga canadensis) and six broadleaf species (Betula populifolia, Malus x domestica, Prunus serotiaa, Quercus lobata, Q. rubra, and Q. velutina) were suitable for L. monacha survival and development. Eleven of the host species tested were rated as intermediate in suitability, four conifer species (Larix occidentalis, P. nigra, P. ponderosa, P. strobus, and Pseudotsuga menziesii variety menziesii) and six broadleaf species (Carpinus caroliniana, Carya ovata, Fagus grandifolia, Populus grandidentata, Q. alba, and Tilia cordata) and the remaining 10 species tested were rated as poor (Acer rubrum, A. platanoidies, A. saccharum, F. americana, Juniperus virginiana, Larix kaempferi, Liriodendron tulipfera, Morus alba, P. taeda, and P. deltoides). The phenological state of the trees had a major impact on establishment, survival, and development of L. monacha on many of the tree species tested. Several of the deciduous tree species that are suitable for L. monacha also are suitable for L. dispar (L.) and L. mathura Moore. Establishment of L. monacha in North America would be catastrophic because of the large number of economically important tree species on which it can survive and develop, and the ability of mated females to fly and colonize new areas.

  11. Toxicity of herbicides on three northwestern conifers.

    Science.gov (United States)

    H. Gratkowski

    1961-01-01

    Vigorous natural reproduction of Douglas-fir, sugar pine, and ponderosa pine in southwestern Oregon was sprayed with 1/2-pound aehg solutions of low volatile esters of 2, 4-D and 2,4, 5-T during 1956. When treated, the trees averaged 4 to 8 feet in height. Treatments were applied during the period of active growth in midsummer and repeated in early autumn after height...

  12. Seed dissemination in small clearcuttings in north-central California

    Science.gov (United States)

    Philip M. McDonald

    1980-01-01

    In a 1964-1967 study on the Challenge Experimental Forest, seedfall was evaluated in 2-, 5-, and 10-acre circular clearcuttings. During the 4 years, 10 seed crops, ranging from light to bumper, were produced by ponderosa pine. white fir, Douglas-fir, and incense cedar. Seedfall ranged from 76 to 40,691 sound seed per acre (188 to lOO,547/ha) for a single species in a...

  13. Contributions of ectomycorrhizal fungal mats to forest soil respiration

    Science.gov (United States)

    C. Phillips; L.A. Kluber; J.P. Martin; B.A. Caldwell; B.J. Bond

    2012-01-01

    Distinct aggregations of fungal hyphae and rhizomorphs, or “mats”, formed by some genera of ectomycorrhizal (EcM) fungi are common features of soils in coniferous forests of the Pacific Northwest. We measured in situ respiration rates of Piloderma mats and neighboring non-mat soils in an old-growth Douglas-fir forest in western Oregon to investigate whether there was...

  14. Field performance of timber bridges. 13, Mohawk Canal stress-laminated bridge

    Science.gov (United States)

    P. D. Hilbrich Lee; X. Lauderdale

    The Mohawk Canal bridge was constructed in August 1994, just outside Roll, Arizona. It is a simple-span, double-lane, stress-laminated deck superstructure, approximately 6.4 m (21 ft) long and 10.4 m (34 ft) wide and constructed with Combination 16F-V3 Douglas Fir glued-laminated timber beam laminations. The performance of the bridge was monitored continuously for 2...

  15. Suggestions for getting more forestry in the logging plan.

    Science.gov (United States)

    Robert H. Ruth; Roy R. Silen

    1950-01-01

    The staggered-setting system of clear-cutting is fast becoming prevailing practice in the Douglas-fir region. The trend is away from large, continuous clear cuts to clear-cutting smaller units of timber of less than 80 acres. These are called staggered settings because the surrounding stand is left uncut to provide seed and serve as a firebreak. Major aims of this...

  16. Manufacture of Strand Board Bonded with Disposal Expanded Polystyrene as Binder

    OpenAIRE

    Hermawan, Andi; Ohuchi, Takeshi; Fujimoto, Noboru; 大内, 毅; 藤本, 登留

    2010-01-01

    The objective of this study was to evaluate the physical and mechanical properties of strand board bonded with disposal expanded polystyrene (EPS) as binder. The strand board was manufactured using strand made from Douglas-fir beams selected from construction scrap wood. The strands were oriented, and two types of three-layer (face-core-face) strand board were manufactured: one in which the board bounded with only disposal EPS (P board), and the other in which the board bonded with disposal...

  17. Logging production rates in young-growth, mixed-conifer stands in north central California

    Science.gov (United States)

    Philip M. McDonald

    1972-01-01

    To quantify production rates for small trees, this study examined the components of log-making and tractor yarding at the Challenge Experimental Forest, Yuba County, California. Rates were calculated over a range of 12 to 40 inches d.b.h. The rate for incense-cedar was lowest; for ponderosa pine it was intermediate; and for Douglas-fir, white fir, and sugar pine...

  18. Ecological setting of the Wind River old-growth forest.

    Science.gov (United States)

    David C. Shaw; Jerry F. Franklin; Ken Bible; Jeffrey Klopatek; Elizabeth Freeman; Sarah Greene; Geoffrey G. Parker

    2004-01-01

    The Wind River old-growth forest, in the southern Cascade Range of Washington State, is a cool (average annual temperature, 8.7°C), moist (average annual precipitation, 2223 mm), 500-year-old Douglas-fir-western hemlock forest of moderate to low productivity at 371-m elevation on a less than 10% slope. There is a seasonal snowpack (November-March), and rain-on-snow and...

  19. Biorefinery lignosulfonates from sulfite-pretreated softwoods as dispersant for graphite

    Science.gov (United States)

    Yanlin Qin; Lixuan Yu; Ruchun Wu; Dongjie Yang; Xueqing Qiu; Junyong Zhu

    2016-01-01

    Two biorefinery lignosulfonates (LSs), Ca-LS-DF and Na-LS-LP were, respectively, isolated from pilot-scale sulfite-pretreated spent liquor of lodgepole pine and fermentation residue of Douglas-fir harvest forest residue. The molecular weights of Na-LS-LP and Ca-LS-DF were approximately 9 000 and 11 000 Da, respectively. The two LSs were applied as dispersant for...

  20. Engineering evaluation of 55-year-old timber columns recycled from an industrial military building

    Science.gov (United States)

    Robert H. Falk; David Green; Douglas Rammer; Scott F. Lantz

    2000-01-01

    A large sample of timber was collected from a 548,000-ft.2 (50,900-m2) World War II era industrial military building containing approximately 1, 875,000 board feet (4,400 m3) of lumber and timber. Sixty 12-foot- (3.6-m-) long, nominal 8- by 8-inches (190-by 190-mm) Douglas-fir columns were tested at the USDA Forest Service, Forest Products Laboratory, and the results...

  1. Wettability and Impact Performance of Wood Veneer/Polyester Composites

    Directory of Open Access Journals (Sweden)

    Shayesteh Haghdan

    2015-07-01

    Full Text Available Fiber-reinforced thermosetting composites have been of interest since the 1940s due to their ease of use in processing, fast curing times, and high specific stiffness and strength. While the use of plant fibers in a polyester matrix has been thoroughly studied, only limited information is available regarding using wood as reinforcement. In this study, composites of thin wood veneer and a polyester matrix were made and the difficulties in the lamination and curing processes were investigated. Sheets of Douglas fir, maple, and oak veneers using a catalyzed polyester resin were assembled as unidirectional, balanced, and unbalanced cross-ply laminates. These were compared to control specimens using glass fiber as reinforcement. The impact properties of the samples, with respect to the laminate thicknesses, were characterized using a drop-weight impact tester. The wettability and surface roughness of unsanded and sanded wood veneers were also investigated. Results showed that Douglas fir cross-ply laminates had an impact energy equivalent to glass fiber laminates, making them an interesting alternative to synthetic fiber composites. Wood/polyester laminates absorbed a considerable amount of energy through a higher number of fracture modes. The balanced lay-up limited twisting of the wood/polyester composites. The lowest contact angle and highest wettability were observed in unsanded Douglas fir veneers.

  2. Effects of Pinus flexilis on the dynamics and structure of plant communities on the northern Rocky Mountain front, and, Training biologists for emerging niches in non-traditional jobs

    Science.gov (United States)

    Baumeister, Dayna Marie

    My research examines the relative importance of interacting mechanisms (amelioration of wind, provision of shade, accumulation of snow pack, and alteration of soil characteristics) governing facilitation between Pinus flexilis and two understory species, Pseudotsuga menziesii and Ribes cereum in Montana. Survival of understory species was greatest beneath P. flexilis at a leeward site (Pseudotsuga, 38% and Ribes, 63%), and lowest in the open at a windward site (2% and 6%, respectively). The effects of wind amelioration, shade provision, and snowdrift accumulation were separated experimentally and after two years, shade was of overwhelming importance for the survival of both species. Once shade was provided, effects of wind amelioration and increased snow pack increased survival, suggesting a hierarchical functioning of mechanisms. High winter mortality of Pseudotsuga suggests P. flexilis canopies may prevent photoinhibition and winter desiccation through reduction of light and insulation from variable temperatures. High summer mortality of Ribes suggests P. flexilis canopies may reduce transpiration through lowering leaf temperatures, thereby decreasing vapor pressure deficits. In this system, several mechanisms governing facilitation operated simultaneously, but in a hierarchical manner of relative importance thereby determining the overall effect of P. flexilis on understory plants. I also studied facilitation and secondary succession by examining understory species composition beneath individual P. flexilis and in P. flexilis stands. As P. flexilis trees and stands aged, understory species richness increased, as did cover of forbs and shrubs, but cover of grasses decreased. Stands currently dominated by P. flexilis are shifting towards dominance by Pseudotsuga primarily in mesic sites, with corresponding increases in litter and shrub cover and decreases in grasses and P. flexilis recruitment. Since the 1860's succession from grasslands to forest on the Front has

  3. Defining how aging Pseudotsuga and Abies compensate for multiple stresses through multi-criteria assessment of a functional-structural model

    Science.gov (United States)

    Maureen C. Kennedy; E. David Ford; Thomas M. Hinckley

    2009-01-01

    Many hypotheses have been advanced about factors that control tree longevity. We use a simulation model with multi-criteria optimization and Pareto optimality to determine branch morphologies in the Pinaceae that minimize the effect of growth limitations due to water stress while simultaneously maximizing carbohydrate gain. Two distinct branch morphologies in the...

  4. Diagnóstico de la Planta de Lixiviación de la oficina Salitrera Santa Laura en Chile. Patrimonio de la Humanidad

    Directory of Open Access Journals (Sweden)

    Ortiz, R.

    2015-12-01

    Full Text Available The Santa Laura Saltpeter Work, which is nowadays the place where the most complete industrial infrastructure of the nitrate processing period is maintained, has a Leaching Tower that is considered by its uniqueness, the icon of the former nitrate industry in Chile. This impressive structure, built mostly in Oregon Pine wood (Pseudotsuga menziesii with metal junctions, unfortunately bears, after the plant stopped producing nitrate and iodine, the impact of its productive past and subsequent human actions because of neglect and lack of maintenance. This report, based on a visual, instrumental and structural inspection, is a diagnosis of the current condition of the building. The results indicate that the elements of the structure, with some exceptions, are in good condition and without changes in their mechanical properties. Structural analysis determined that the plant behavior is favorable, being able to withstand a seismic event of importance.La oficina salitrera Santa Laura, que es actualmente el lugar donde se mantiene la infraestructura industrial más completa del periodo del procesamiento del salitre, posee una Torre de Lixiviación que es considerada, por su singularidad, el ícono de la otrora industria salitrera en Chile. Esta impresionante estructura, construida casi en su totalidad con madera de Pino Oregón (Pseudotsuga menziesii y elementos metálicos en sus uniones, sobrelleva desafortunadamente, después del cese del proceso de fabricación de salitre y yodo, el impacto de su pasado productivo y posteriores acciones antrópicasambientales producto de su abandono y falta de mantenimiento. El presente informe, que contemplo inspección básica, instrumental y análisis estructural, es un diagnóstico del estado actual de conservación del edificio. Los resultados obtenidos indican que los elementos que conforman la estructura, con algunas excepciones, se encuentran en buen estado y sin alteración de sus propiedades mecánicas. El

  5. Pilot plant studies of the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1977-01-31

    Progress is reported in several areas of research. The following cellulosic raw materials were selected for study: wheat, barley, and rice straws, rice hulls, sorghum, corn stover, cotton gin trash, newsprint, ground wood, and masonite steam-treated Douglas fir and redwood. Samples were collected, prepared, and analyzed for hexosans, pentosans, lignin, ash, and protein. Results of acid extraction and enzymatic hydrolysis are discussed. Yields of glucose, polyglucose, xylose, and arabinose are reported. Progress in process design and economic studies, as well as pilot plant process development and design studies, is summarized. (JGB)

  6. Acid hydrolysis of the biomass of resistant cellulose of thistle ''Onopordum nervosum boiss''

    International Nuclear Information System (INIS)

    Suarez, C.; Diaz Palma, A.; Paz Saa, M.D.

    1985-01-01

    Hydrolysis of resistant cellulose of ''Onopordum nervosum boiss'' (thistle) to reduce sugar in diluted sulfuric acid in glass ampoules and long residence times have been studied and kinetic parameters determined. The rate of hydrolysis is similar to that of the cellulose of Douglas fir, but comparatively the effect of the acid is more pronounced than temperature. From kinetic data the yield can be predicted and since it can be obtained at least 45% of the potential glucose (48% as reducing sugars) at 190 deg C, 1.6% acid and 6.1 min. residence time, it indicates that the continuous acid hydrolysis of thistle may be a process of commercial interest. (author)

  7. Mixed-Mode Crack Growth in Wood

    Directory of Open Access Journals (Sweden)

    Octavian POP

    2012-09-01

    Full Text Available In timber elements the mixed mode dependsessentially of wood anatomy and load configuration.In these conditions, in order to evaluate the materialbehavior and the fracture process, it’s necessary toseparate the part of each mode. The mixed modeseparation allows evaluating the amplitude offracture mode. In the present paper, using a mixedmodecrack growth specimen made in Douglas fir,the mixed mode crack growth process is studythanks to marks tracking method. Using the markstracking method the characteristic displacementsassociated to opening and shear mode aremeasured. From the experimental measurements,the energy release rate associated to opening andshear modes is calculated into to account the crackadvancement during the test.

  8. How much does climate change threaten European forest tree species distributions?

    Science.gov (United States)

    Dyderski, Marcin K; Paź, Sonia; Frelich, Lee E; Jagodziński, Andrzej M

    2018-03-01

    Although numerous species distribution models have been developed, most were based on insufficient distribution data or used older climate change scenarios. We aimed to quantify changes in projected ranges and threat level by the years 2061-2080, for 12 European forest tree species under three climate change scenarios. We combined tree distribution data from the Global Biodiversity Information Facility, EUFORGEN, and forest inventories, and we developed species distribution models using MaxEnt and 19 bioclimatic variables. Models were developed for three climate change scenarios-optimistic (RCP2.6), moderate (RCP4.5), and pessimistic (RPC8.5)-using three General Circulation Models, for the period 2061-2080. Our study revealed different responses of tree species to projected climate change. The species may be divided into three groups: "winners"-mostly late-successional species: Abies alba, Fagus sylvatica, Fraxinus excelsior, Quercus robur, and Quercus petraea; "losers"-mostly pioneer species: Betula pendula, Larix decidua, Picea abies, and Pinus sylvestris; and alien species-Pseudotsuga menziesii, Quercus rubra, and Robinia pseudoacacia, which may be also considered as "winners." Assuming limited migration, most of the species studied would face a significant decrease in suitable habitat area. The threat level was highest for species that currently have the northernmost distribution centers. Ecological consequences of the projected range contractions would be serious for both forest management and nature conservation. © 2017 John Wiley & Sons Ltd.

  9. Identification case of evidence in timber tracing of Pinus radiate, using high-resolution melting (HRM) analysis.

    Science.gov (United States)

    Solano, Jaime; Anabalón, Leonardo; Encina, Francisco

    2016-03-01

    Fast, accurate detection of plant species and their hybrids using molecular tools will facilitate assessment and monitoring of timber tracing evidence. In this study the origin of unknown pine samples is determined for a case of timber theft in the region of Araucania southern Chile. We evaluate the utility of the trnL marker region for species identification applied to pine wood based on High Resolution Melting. This efficient tracing methods can be incorporated into forestry applications such as certification of origin. The object of this work was genotype identification using high-resolution melting (HRM) and trnL approaches for Pinus radiata (Don) in timber tracing evidence. Our results indicate that trnL is a very sensitive marker for delimiting species and HRM analysis was used successfully for genotyping Pinus samples for timber tracing purposes. Genotyping samples by HRM analysis with the trnL1 approach allowed us to differentiate two wood samples from the Pinaceae family: Pinus radiata (Don) and Pseudotsuga menziesii (Mirb.) Franco. The same approach with Pinus trnL wood was not able to discriminate between samples of Pinus radiata, indicating that the samples were genetically indistinguishable, possibly because they have the same genotype at this locus. Timber tracing with HRM analysis is expected to contribute to future forest certification schemes, control of illegal trading, and molecular traceability of Pinus spp. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Evolution of the YABBY gene family in seed plants.

    Science.gov (United States)

    Finet, Cédric; Floyd, Sandra K; Conway, Stephanie J; Zhong, Bojian; Scutt, Charles P; Bowman, John L

    2016-01-01

    Members of the YABBY gene family of transcription factors in angiosperms have been shown to be involved in the initiation of outgrowth of the lamina, the maintenance of polarity, and establishment of the leaf margin. Although most of the dorsal-ventral polarity genes in seed plants have homologs in non-spermatophyte lineages, the presence of YABBY genes is restricted to seed plants. To gain insight into the origin and diversification of this gene family, we reconstructed the evolutionary history of YABBY gene lineages in seed plants. Our findings suggest that either one or two YABBY genes were present in the last common ancestor of extant seed plants. We also examined the expression of YABBY genes in the gymnosperms Ephedra distachya (Gnetales), Ginkgo biloba (Ginkgoales), and Pseudotsuga menziesii (Coniferales). Our data indicate that some YABBY genes are expressed in a polar (abaxial) manner in leaves and female cones in gymnosperms. We propose that YABBY genes already acted as polarity genes in the last common ancestor of extant seed plants. © 2016 Wiley Periodicals, Inc.

  11. Decomposition and nitrogen dynamics of 15N-labeled leaf, root, and twig litter in temperate coniferous forests

    Science.gov (United States)

    van Huysen, Tiff L.; Harmon, Mark E.; Perakis, Steven S.; Chen, Hua

    2013-01-01

    Litter nutrient dynamics contribute significantly to biogeochemical cycling in forest ecosystems. We examined how site environment and initial substrate quality influence decomposition and nitrogen (N) dynamics of multiple litter types. A 2.5-year decomposition study was installed in the Oregon Coast Range and West Cascades using 15N-labeled litter from Acer macrophyllum, Picea sitchensis, and Pseudotsuga menziesii. Mass loss for leaf litter was similar between the two sites, while root and twig litter exhibited greater mass loss in the Coast Range. Mass loss was greatest from leaves and roots, and species differences in mass loss were more prominent in the Coast Range. All litter types and species mineralized N early in the decomposition process; only A. macrophyllum leaves exhibited a net N immobilization phase. There were no site differences with respect to litter N dynamics despite differences in site N availability, and litter N mineralization patterns were species-specific. For multiple litter × species combinations, the difference between gross and net N mineralization was significant, and gross mineralization was 7–20 % greater than net mineralization. The mineralization results suggest that initial litter chemistry may be an important driver of litter N dynamics. Our study demonstrates that greater amounts of N are cycling through these systems than may be quantified by only measuring net mineralization and challenges current leaf-based biogeochemical theory regarding patterns of N immobilization and mineralization.

  12. Estimating biogenic contributions to secondary pollutants: formation at regional scale (Fosse Rhenan, France); Impact des emissions naturelles sur les episodes de pollution photochimique: application a la region du Fosse Rhenan

    Energy Technology Data Exchange (ETDEWEB)

    Moukhtar, S.

    2005-02-15

    Biotic volatile organic compounds (VOCs) play a significant role in the formation and development of photochemical pollution events. In this context, the integration of biotic VOCs in the CHIMERE chemical transport model has been improved by the use of a double numerical and experimental approach. Field measurements have permitted to determine the flux of emissions of biotic VOCs from three tree species particularly abundant in France: Abies alba, Fagus sylvatica and Pseudotsuga menziesii. A database has been updated and used to estimate the annual VOC emissions by the French forestry system. A critical synthesis of the bibliography about the reactivity of biotic VOCs has led to the elaboration of a new chemical mechanism which has been implemented in the CHIMERE model. The results of this model have been compared to the observations available for the region of the Rhine through (Fosse Rhenan) characterized by strong biotic VOC emissions. These modifications does not change much the ozone concentrations but they have strong impacts on the modeling of peroxy-acetyl-nitrate (PAN) and formaldehyde concentrations. (J.S.)

  13. Decomposition and nitrogen dynamics of (15)N-labeled leaf, root, and twig litter in temperate coniferous forests.

    Science.gov (United States)

    van Huysen, Tiff L; Harmon, Mark E; Perakis, Steven S; Chen, Hua

    2013-12-01

    Litter nutrient dynamics contribute significantly to biogeochemical cycling in forest ecosystems. We examined how site environment and initial substrate quality influence decomposition and nitrogen (N) dynamics of multiple litter types. A 2.5-year decomposition study was installed in the Oregon Coast Range and West Cascades using (15)N-labeled litter from Acer macrophyllum, Picea sitchensis, and Pseudotsuga menziesii. Mass loss for leaf litter was similar between the two sites, while root and twig litter exhibited greater mass loss in the Coast Range. Mass loss was greatest from leaves and roots, and species differences in mass loss were more prominent in the Coast Range. All litter types and species mineralized N early in the decomposition process; only A. macrophyllum leaves exhibited a net N immobilization phase. There were no site differences with respect to litter N dynamics despite differences in site N availability, and litter N mineralization patterns were species-specific. For multiple litter × species combinations, the difference between gross and net N mineralization was significant, and gross mineralization was 7-20 % greater than net mineralization. The mineralization results suggest that initial litter chemistry may be an important driver of litter N dynamics. Our study demonstrates that greater amounts of N are cycling through these systems than may be quantified by only measuring net mineralization and challenges current leaf-based biogeochemical theory regarding patterns of N immobilization and mineralization.

  14. Belowground legacies of Pinus contorta invasion and removal result in multiple mechanisms of invasional meltdown.

    Science.gov (United States)

    Dickie, Ian A; St John, Mark G; Yeates, Gregor W; Morse, Chris W; Bonner, Karen I; Orwin, Kate; Peltzer, Duane A

    2014-01-01

    Plant invasions can change soil biota and nutrients in ways that drive subsequent plant communities, particularly when co-invading with belowground mutualists such as ectomycorrhizal fungi. These effects can persist following removal of the invasive plant and, combined with effects of removal per se, influence subsequent plant communities and ecosystem functioning. We used field observations and a soil bioassay with multiple plant species to determine the belowground effects and post-removal legacy caused by invasion of the non-native tree Pinus contorta into a native plant community. Pinus facilitated ectomycorrhizal infection of the co-occurring invasive tree, Pseudotsuga menziesii, but not conspecific Pinus (which always had ectomycorrhizas) nor the native pioneer Kunzea ericoides (which never had ectomycorrhizas). Pinus also caused a major shift in soil nutrient cycling as indicated by increased bacterial dominance, NO3-N (17-fold increase) and available phosphorus (3.2-fold increase) in soils, which in turn promoted increased growth of graminoids. These results parallel field observations, where Pinus removal is associated with invasion by non-native grasses and herbs, and suggest that legacies of Pinus on soil nutrient cycling thus indirectly promote invasion of other non-native plant species. Our findings demonstrate that multi-trophic belowground legacies are an important but hitherto largely unconsidered factor in plant community reassembly following invasive plant removal. Published by Oxford University Press on behalf of the Annals of Botany Company.

  15. Coniferous tree plantations in forest conditions-economic analysis of dedicated and semi-dedicated pathways to increase wood production

    International Nuclear Information System (INIS)

    Rakotoarison, Hanitra; Richter, Claudine; Cailly, Priscilla; Deleuze, Christine; Berthelot, Alain

    2015-01-01

    To meet growing demand for wood, particularly softwoods, the authors study a number of new silvicultural pathways for planting 3 species: Douglas fir, spruce and maritime pine. The goal of these pathways is to achieve specialised production of either industrial and workable timber, or a mixture of industrial and workable timber with medium-diameter workable timber. Pathways of this type have already been standardised for hardwoods, generally on fertile farmland. In a less fertile forest context, softwoods have a significant potential for woody production but specialized pathways and their profitability have yet to be studied. This article describes the innovative work being done to construct and simulate profitable production, new potential pathways, where plantation density, rotation time, the level of fertility are made to vary using the data from the FCBA test network in conjunction with the FCBA growth models (Oasis for spruce and Douglas fir, Sylveco for maritime pine). Economic data is derived from auction sales statistics and the ONF management and forestry work costs for the period 2012-2015. The Economics module developed by FCBA and ONF on the Capsis platform in the framework of the ICI project (Futurol) was used for the economic simulations. The analyses show that compared to conventional pathways, these pathways generally increase productivity but are nonetheless less profitable than current economic assumptions, although results vary according to species, fertility and the particular pathway. The sensitivity study shows that variations in the price of wood could alter the performance ratings as between conventional and specialised pathways. (authors)

  16. Assessment of hydrothermal pretreatment of various lignocellulosic biomass with CO2 catalyst for enhanced methane and hydrogen production.

    Science.gov (United States)

    Eskicioglu, Cigdem; Monlau, Florian; Barakat, Abdellatif; Ferrer, Ivet; Kaparaju, Prasad; Trably, Eric; Carrère, Hélène

    2017-09-01

    Hydrothermal pretreatment of five lignocellulosic substrates (i.e. wheat straw, rice straw, biomass sorghum, corn stover and Douglas fir bark) were conducted in the presence of CO 2 as a catalyst. To maximize disintegration and conversion into bioenergy (methane and hydrogen), pretreatment temperatures and subsequent pressures varied with a range of 26-175 °C, and 25-102 bars, respectively. Among lignin, cellulose and hemicelluloses, hydrothermal pretreatment caused the highest reduction (23-42%) in hemicelluloses while delignification was limited to only 0-12%. These reductions in structural integrity resulted in 20-30% faster hydrolysis rates during anaerobic digestion for the pretreated substrates of straws, sorghum, and corn stover while Douglas fir bark yielded 172% faster hydrolysis/digestion due to its highly refractory nature in the control. Furans and phenolic compounds formed in the pretreated hydrolyzates were below the inhibitory levels for methane and hydrogen production which had a range of 98-340 ml CH 4 /g volatile solids (VS) and 5-26 ml H 2 /g VS, respectively. Results indicated that hydrothermal pretreatment is able to accelerate the rate of biodegradation without generating high levels of inhibitory compounds while showing no discernible effect on ultimate biodegradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Bark, a suitable bio-sorbent for the removal of uranium from wastewater - From laboratory to industry

    International Nuclear Information System (INIS)

    Jauberty, L.; Delpech, V.; Gloaguen, V.; Astier, C.; Krausz, P.; Berland, A.; Granger, V.; Niort, I.; Royer, A.; Decossas, J.L.

    2011-01-01

    This paper shows that natural materials such as barks can successfully replace synthetic resins for industrial purposes. Evaluated in batch conditions, bio-sorption of uranium on suitably prepared Douglas fir barks took place in less than 10 min and appeared to be optimum at pH>4. The bio-sorption process of uranium (uranyl form UO 2 2+ ) was characterized in the optimal physico-chemical conditions and could be mathematically modeled as a Langmuir isotherm. With a maximum uranium specific uptake q max value of 1.16 meq.g -1 (138 mgU.g -1 ) it was found that the sorption capability of Douglas fir barks was at least five times higher for uranium than for other heavy metals such as lead. Adsorption of uranium contained in water leached from a former uranium mine was then monitored over a one-month period in a laboratory-scale chromatography column. The fixation capacity remained fairly constant throughout the whole testing period. Water radioactivity decreased from 1500 mBq.L -1 (0.12 mgU.L -1 ) to -1 (0.4 μgU.L -1 ) at the column exit. This technology was successfully transferred and tested through a pilot project under industrial conditions with the support of AREVA NC. (authors)

  18. Native fauna on exotic trees: phylogenetic conservatism and geographic contingency in two lineages of phytophages on two lineages of trees.

    Science.gov (United States)

    Gossner, Martin M; Chao, Anne; Bailey, Richard I; Prinzing, Andreas

    2009-05-01

    The relative roles of evolutionary history and geographical and ecological contingency for community assembly remain unknown. Plant species, for instance, share more phytophages with closer relatives (phylogenetic conservatism), but for exotic plants introduced to another continent, this may be overlaid by geographically contingent evolution or immigration from locally abundant plant species (mass effects). We assessed within local forests to what extent exotic trees (Douglas-fir, red oak) recruit phytophages (Coleoptera, Heteroptera) from more closely or more distantly related native plants. We found that exotics shared more phytophages with natives from the same major plant lineage (angiosperms vs. gymnosperms) than with natives from the other lineage. This was particularly true for Heteroptera, and it emphasizes the role of host specialization in phylogenetic conservatism of host use. However, for Coleoptera on Douglas-fir, mass effects were important: immigration from beech increased with increasing beech abundance. Within a plant phylum, phylogenetic proximity of exotics and natives increased phytophage similarity, primarily in younger Coleoptera clades on angiosperms, emphasizing a role of past codiversification of hosts and phytophages. Overall, phylogenetic conservatism can shape the assembly of local phytophage communities on exotic trees. Whether it outweighs geographic contingency and mass effects depends on the interplay of phylogenetic scale, local abundance of native tree species, and the biology and evolutionary history of the phytophage taxon.

  19. Leaf water 18 O and 2 H enrichment along vertical canopy profiles in a broadleaved and a conifer forest tree.

    Science.gov (United States)

    Bögelein, Rebekka; Thomas, Frank M; Kahmen, Ansgar

    2017-07-01

    Distinguishing meteorological and plant-mediated drivers of leaf water isotopic enrichment is prerequisite for ecological interpretations of stable hydrogen and oxygen isotopes in plant tissue. We measured input and leaf water δ 2 H and δ 18 O as well as micrometeorological and leaf morpho-physiological variables along a vertical gradient in a mature angiosperm (European beech) and gymnosperm (Douglas fir) tree. We used these variables and different enrichment models to quantify the influence of Péclet and non-steady state effects and of the biophysical drivers on leaf water enrichment. The two-pool model accurately described the diurnal variation of leaf water enrichment. The estimated unenriched water fraction was linked to leaf dry matter content across the canopy heights. Non-steady state effects and reduced stomatal conductance caused a higher enrichment of Douglas fir compared to beech leaf water. A dynamic effect analyses revealed that the light-induced vertical gradients of stomatal conductance and leaf temperature outbalanced each other in their effects on evaporative enrichment. We conclude that neither vertical canopy gradients nor the Péclet effect is important for estimates and interpretation of isotopic leaf water enrichment in hypostomatous trees. Contrarily, species-specific non-steady state effects and leaf temperatures as well as the water vapour isotope composition need careful consideration. © 2017 John Wiley & Sons Ltd.

  20. Calibrating and testing a gap model for simulating forest management in the Oregon Coast Range

    Science.gov (United States)

    Pabst, R.J.; Goslin, M.N.; Garman, S.L.; Spies, T.A.

    2008-01-01

    The complex mix of economic and ecological objectives facing today's forest managers necessitates the development of growth models with a capacity for simulating a wide range of forest conditions while producing outputs useful for economic analyses. We calibrated the gap model ZELIG to simulate stand-level forest development in the Oregon Coast Range as part of a landscape-scale assessment of different forest management strategies. Our goal was to incorporate the predictive ability of an empirical model with the flexibility of a forest succession model. We emphasized the development of commercial-aged stands of Douglas-fir, the dominant tree species in the study area and primary source of timber. In addition, we judged that the ecological approach of ZELIG would be robust to the variety of other forest conditions and practices encountered in the Coast Range, including mixed-species stands, small-scale gap formation, innovative silvicultural methods, and reserve areas where forests grow unmanaged for long periods of time. We parameterized the model to distinguish forest development among two ecoregions, three forest types and two site productivity classes using three data sources: chronosequences of forest inventory data, long-term research data, and simulations from an empirical growth-and-yield model. The calibrated model was tested with independent, long-term measurements from 11 Douglas-fir plots (6 unthinned, 5 thinned), 3 spruce-hemlock plots, and 1 red alder plot. ZELIG closely approximated developmental trajectories of basal area and large trees in the Douglas-fir plots. Differences between simulated and observed conifer basal area for these plots ranged from -2.6 to 2.4 m2/ha; differences in the number of trees/ha ???50 cm dbh ranged from -8.8 to 7.3 tph. Achieving these results required the use of a diameter-growth multiplier, suggesting some underlying constraints on tree growth such as the temperature response function. ZELIG also tended to overestimate