The alpha-tocopherol content of leaves of pedunculate oak (Quercus robur L.)--variation over the growing season and along the vertical light gradient in the canopy.

Science.gov (United States)

Hansen, Ute; Schneiderheinze, Jenny; Stadelmann, Simone; Rank, Barbara

2003-01-01

This study was performed in order to investigate whether the actual requirement for defence against photo-oxidative stress is reflected by the alpha-tocopherol (alpha-Toco) content in leaves of pedunculate oak (Quercus robur L.). Antioxidants and pigments were quantified in leaves that were collected on six days between May and September 2000 in a mixed pine/oak forest at canopy positions differing in light environment. Pools of hydrophilic antioxidants and photo-protective xanthophyll cycle pigments (V + A + Z) reflected the anti-oxidative demand, as these pools increased with the average light intensity to which the leaves were acclimated. The photo-protective demand was not the determinant of the alpha-Toco content of oak leaves, as (1) foliage of a young oak, exposed to low light levels in the understorey, contained higher amounts of this lipophilic antioxidant than leaves sampled from semimature oaks at canopy positions with a similar light environment, and (2) a strong increase in the alpha-Toco content over the growing season was detected at each investigated crown position, whereas the V + A + Z pool did not show a concomitant accumulation during leaf ageing. The rate of alpha-Toco accumulation differed distinctly between samples taken at different canopy positions.

The Hibernation of the oak Mildew

NARCIS (Netherlands)

Kerling, L.C.P.

1966-01-01

The oak mildew invaded Western Europa in the years 1908 and 1909. Since then this parasite, Microsphaera alphitoides Griff. & Maubl. (syn. M. quercina (Schw.) Burr.) has occurred regularly in the Netherlands on oak seedlings and oak coppice, mainly Quercus pedunculata Ehr. (syn. Q. robur L. ). After

PAH detection in Quercus robur leaves and Pinus pinaster needles: A fast method for biomonitoring purpose.

Science.gov (United States)

De Nicola, F; Concha Graña, E; Aboal, J R; Carballeira, A; Fernández, J Á; López Mahía, P; Prada Rodríguez, D; Muniategui Lorenzo, S

2016-06-01

Due to the complexity and heterogeneity of plant matrices, new procedure should be standardized for each single biomonitor. Thus, here is described a matrix solid-phase dispersion extraction method, previously used for moss samples, improved and modified for the analyses of PAHs in Quercus robur leaves and Pinus pinaster needles, species widely used in biomonitoring studies across Europe. The improvements compared to the previous procedure are the use of Florisil added with further clean-up sorbents, 10% deactivated silica for pine needles and PSA for oak leaves, being these matrices rich in interfering compounds, as shown by the gas chromatography-mass spectrometry analyses acquired in full scan mode. Good trueness, with values in the range 90-120% for the most of compounds, high precision (intermediate precision between 2% and 12%) and good sensitivity using only 250mg of samples (limits of quantification lower than 3 and 1.5ngg(-1), respectively for pine and oak) were achieved by the selected procedures. These methods proved to be reliable for PAH analyses and, having advantage of fastness, can be used in biomonitoring studies of PAH air contamination. Copyright © 2016 Elsevier B.V. All rights reserved.

Evidence for hybridization and introgression within a species-rich oak (Quercus spp. community

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Finkeldey Reiner

2007-11-01

Full Text Available Abstract Background Analysis of interspecific gene flow is crucial for the understanding of speciation processes and maintenance of species integrity. Oaks (genus Quercus, Fagaceae are among the model species for the study of hybridization. Natural co-occurrence of four closely related oak species is a very rare case in the temperate forests of Europe. We used both morphological characters and genetic markers to characterize hybridization in a natural community situated in west-central Romania and which consists of Quercus robur, Q. petraea, Q. pubescens, and Q. frainetto, respectively. Results On the basis of pubescence and leaf morphological characters ~94% of the sampled individuals were assigned to pure species. Only 16 (~6% individual trees exhibited intermediate morphologies or a combination of characters of different species. Four chloroplast DNA haplotypes were identified in the study area. The distribution of haplotypes within the white oak complex showed substantial differences among species. However, the most common haplotypes were present in all four species. Furthermore, based on a set of 7 isozyme and 6 microsatellite markers and using a Bayesian admixture analysis without any a priori information on morphology we found that four genetic clusters best fit the data. There was a very good correspondence of each species with one of the inferred genetic clusters. The estimated introgression level varied markedly between pairs of species ranging from 1.7% between Q. robur and Q. frainetto to 16.2% between Q. pubescens and Q. frainetto. Only nine individuals (3.4% appeared to be first-generation hybrids. Conclusion Our data indicate that natural hybridization has occurred at relatively low rates. The different levels of gene flow among species might be explained by differences in flowering time and spatial position within the stand. In addition, a partial congruence between phenotypically and genetically intermediate individuals was

Analysis of oak tannins by liquid chromatography-electrospray ionisation mass spectrometry.

Science.gov (United States)

Mämmelä, P; Savolainen, H; Lindroos, L; Kangas, J; Vartiainen, T

2000-09-01

Extractable tannins were analysed by liquid chromatography-electrospray ionisation mass spectrometry in two oak species, North American white oak (Quercus alba) and European red oak (Quercus robur). They mainly included various glucose gallic and ellagic acid esters. The structures were partially determined, and they included grandinin/roburin E, castalagin/vescalagin, gallic acid, valoneic acid bilactone, monogalloyl glucose, digalloyl glucose, trigalloyl glucose, ellagic acid rhamnose, quercitrin and ellagic acid.

A 20-Year Overview of Quercus robur L. Mortality and Crown Conditions in Slovenia

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Matjaž Čater

2015-02-01

Full Text Available Pedunculate oak (Quercus robur L. forests in Slovenia are experiencing widespread mortality. Changes in lowlands are reflected in decline of complete forest complexes, high mortality, uneven stand structure and associated forest regeneration problems. Prediction of the present-tree response in disturbed forest ecosystems may significantly contribute to better guideline policies for the silvicultural and forest management practice in the changing environment in both stressed and stabile forest ecosystems. Data from annual crown condition surveys for the 1995–2014 period from four permanent plots have been compared with parameters from hemispherical photo analysis and hydrometeorological data. Good agreement has been confirmed between crown defoliation and total openness; all parameters from the hemispherical photo analysis, which were corrected for winter period values, also indicated a better agreement. Mortality rate and crown defoliation correlated well with extreme drought events in 2003 and 2013. Pattern of agreement among compared parameters was different for the plots Krakovski gozd, Dobrava and some other plots. Mortality is influenced by the average air temperatures much more than by precipitation and groundwater table oscillations.

Quercus kelloggii Newb., California black oak

Science.gov (United States)

P.M. McDonald

1990-01-01

California black oak (Quercus kelloggii) exceeds all other California oaks in volume, distribution, and altitudinal range. Yet this deciduous hardwood has had little sustained commercial use and almost no management, even though its wood closely resembles that of its valuable, managed, and heavily used counterpart-northern red oak (...

Ultraviolet-B radiation influences the abundance and distribution of phylloplane fungi on pedunculate oak (Quercus robur)

International Nuclear Information System (INIS)

Newsham, K.K.; Low, M.N.R.; McLeod, A.R.; Greenslade, P.D.; Emmett, B.A.

1997-01-01

The effects of u.v.-B radiation (280-315 nm) on the fungi occurring on the lammas leaves of pedunculate oak (Quercus robur L.) were examined using saplings that were exposed at an outdoor facility to supplemental levels of u.v.-B radiation under treatment arrays of cellulose diacetate-filtered fluorescent lamps, which also produce u.v.-A radiation (315-400 nm). Saplings were also exposed to u.v.-A radiation alone under control arrays of polyester-filtered lamps, and to ambient levels of solar radiation under arrays of unenergized lamps. The u.v.-B treatment corresponded to a 30% elevation above the ambient level of erythemally-weighted u.v.-B radiation. The fungi were examined weekly over a 4-month-period in summer and autumn 1995 using two techniques, the spore fall and leaf impression methods, which differentiated between those fungi occurring on the upper (adaxial) and lower (abaxial) surfaces of the leaves. The abundances of Aureobasidium pullulans (De Bary) Arnaud and Sporobolomyces roseus Kluy. et van Niel, two leaf yeasts which had adaxial:abaxial ratios of < 1 under ambient levels of u.v.-B radiation, were negatively correlated with increasing ambient levels of u.v.-B radiation and were significantly reduced on adaxial leaf surfaces by supplemental levels of u.v.-B. There were few effects of supplemental u.v.-B radiation on the abundances of these yeasts on abaxial leaf surfaces. The abundances of the dematiaceous hyphomycetes, Cladosporium spp. and Epicoccum nigrum Link., species with adaxial:abaxial ratios of ⩾ 1 under ambient levels of u.v.-B radiation, were not correlated with ambient levels of u.v.-B radiation, nor were they usually affected on either leaf surface by supplemental u.v.-B radiation. Alternaria spp. and Microdochium nivale (Fr.) Samuels & Hallet showed consistent responses on adaxial leaf surfaces to u.v.-A radiation applied under control and treatment arrays. Our results suggest that current levels of shortwave radiation already

Effects of above- and below-ground competition from shrubs on photosynthesis, transpiration and growth in Quercus robur L

Science.gov (United States)

Anna M. Jensen; Magnus Lof; Emile S. Gardiner

2011-01-01

For a tree seedling to successfully establish in dense shrubbery, it must maintain function under heterogeneous resource availability. We evaluated leaf-level acclimation in photosynthetic capacity, seedling-level transpiration, and seedling morphology and growth to gain an understanding of the effects of above- and below-ground competition on Quercus robur seedlings....

Associations between growth, wood anatomy, carbon isotope discrimination and mortality in a Quercus robur forest.

Science.gov (United States)

Levanic, Tom; Cater, Matjaz; McDowell, Nate G

2011-03-01

Observations of forest mortality are increasing globally, but relatively little is known regarding the underlying mechanisms driving these events. Tree rings carry physiological signatures that may be used as a tool for retrospective analyses. We capitalized on a local soil water drainage event in 1982 that resulted in increased mortality within a stand of oak trees (Quercus robur), to examine the underlying physiological patterns associated with survival and death in response to soil water limitations. Pre-dawn water potentials showed more negative values for trees in the process of dying compared with those that survived. We used tree rings formed over the 123 years prior to mortality to estimate productivity from basal area increment (BAI, mm(2)), multiple xylem hydraulic parameters via anatomical measurements and crown-level gas exchange via carbon isotope discrimination (Δ, ‰). Oaks that died had significantly higher BAI values than trees that survived until the drainage event, after which the BAI of trees that died declined dramatically. Hydraulic diameter and conductivity of vessels in trees that died were higher than in surviving trees until the last 5 years prior to mortality, at which time both groups had similar values. Trees that died had consistently lower Δ values than trees that survived. Therefore, tree mortality in this stand was associated with physiological differences prior to the onset of soil water reduction. We propose that trees that died may have been hydraulically underbuilt for dry conditions, which predisposes them to severe hydraulic constraints and subsequent mortality. Measurements of above-ground/below-ground dry mass partitioning will be critical to future tests of this hypothesis. Based on these results, it is probable that pedunculate oak trees will experience greater future mortality if climate changes cause more severe droughts than the trees have experienced previously.

Isolation and characterization of repeat elements of the oak genome and their application in population analysis

International Nuclear Information System (INIS)

Fluch, S.; Burg, K.

1998-01-01

Four minisatellite sequence elements have been identified and isolated from the genome of the oak species Quercus petraea and Quercus robur. Minisatellites 1 and 2 are putative members of repeat families, while minisatellites 3 and 4 show repeat length variation among individuals of test populations. A 590 base pair (bp) long element has also been identified which reveals individual-specific autoradiographic patterns when used as probe in Southern hybridisations of genomic oak DNA. (author)

Fungi and minerals occurring in heartwood discolorations in Ouercus robur trees

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Krystyna Przybył

2011-01-01

Full Text Available The studied Quercus robur trees were oaks protected as monuments of nature (200-350 years old and oaks growing in forest stands (200-300 years old. The most visible symptoms occurring in aboveground organs included defoliation (25-75%, dying of twigs and branches. Discoloured heartwood, obtained with an 80-cm Pressler borer, differed in colour intensity from normal wood and was divided into two groups: stained brown and dark brown. The brown-stained heartwood was a more active site, considering the number of fungi and their ability to produce enzymes (phenoloxidase, pectinase and cellulase in comparison with the dark-brown-stained heartwood. This brown-stained heartwood contained also statistically more Ca, Mg and Mn.

Evolution of ellagitannins in Spanish, French, and American oak woods during natural seasoning and toasting.

Science.gov (United States)

Cadahía, E; Varea, S; Muñoz, L; Fernández De Simón, B; García-Vallejo, M C

2001-08-01

The evolution of tannins in Spanish oak heartwood of Quercus robur L., Quercus petraea Liebl.,Quercus pyrenaica Wild., and Quercus faginea Lam. was studied in relation to the processing of wood in barrel cooperage. Their evolution was compared with that of French oak of Q. robur (Limousin, France) and Q. petraea (Allier, France) and American oak of Quercus alba L. (Missouri), which are habitually used in cooperage. Two stages of process were researched: the seasoning of woods during 3 years in natural conditions and toasting. Total phenol and total ellagitannin contents and optical density at 420 nm of wood extracts were determined. The ellagitannins roburins A-E, grandinin, vescalagin, and castalagin were identified and quantified by HPLC, and the molecular weight distribution of ellagitannins was calculated by GPC. During the seasoning process the different ellagitannin concentrations decreased according to the duration of this process and in the same way as those in French and American woods. The toasting process also had an important influence on the ellagitannin composition of wood. Roburins A-E, grandinin, vescalagin, and castalagin decreased during this process in the Spanish wood species, in the same proportion as in the French and American ones. Also, the seasoning and toasting processes lead to qualitative variations in the structure of ellagitannins, especially in the molecular weight distribution, as was evidenced by GPC analysis of their acetylated derivatives.

Onderzoek naar de relatie tussen het zoutgehalte van de bodem, de bodemvruchtbaarheid, de vegetatie, de bladsamenstelling en de boniteit van opstanden van zomereik (Quercus robur) in de boswachterij Wieringermeer (voorjaar-najaar 1981) = Investigation of relationships between soil salinity, soil fertility, natural vegetation, foliar composition and site index of stands of pedunculate oak (Q.robur)

NARCIS (Netherlands)

Burg, van den J.; Leys, H.N.; Lynden, van K.R.

1984-01-01

Het verband tussen de natuurlijke vegetatie, het bodemprofiel, de bodemchemische eigenschappen, de grondwaterstand, het zoutgehalte van de bodem en de boniteit van zomereik (Quercus robur) werd in 1981 onderzocht in 26 proefplekken in de boswachterij Wieringermeer. Het doel van het onderzoek in deze

CHANGES IN VOLATILE COMPOSITION AND SENSORY PROPERTIES OF VUGAVA WINES AGED IN CROATIA OAK BARRELS

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Stanka HERJAVEC

2001-09-01

Full Text Available Vugava musts were fermented in medium-toasted Croatian barrique barrels (225 L made from Quercus petrea and Q. robur oak wood. The oak species used in this research infl uenced the specifi c change of the aroma structure of Vugava wines. During the age period the increase in the concentration of cis and trans oaklactons, guaiacol, eugenol, furfural and 5-methylfurfural was noted. Wines fermented and aged in Q. petrea barrels have higher concentrations of most volatile phenols compared to wines from Q. robur oak wood. From the organoleptic point of view this study suggested that fermentation and on the lees ageing production method in Croatian oak barrels positively infl uenced the quality of Vugava wines where best results were achieved by use of Q. petrea oak wood.

Development of gypsy moth (Lymantria dispar L on the foliage of Quercus cerris L., Q. Petraea (matt Liebl. and Q. Robur L. in the controlled conditions

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Milanović Slobodan

2007-01-01

Full Text Available The development of Gypsy moth (Lymantria dispar L was monitored in laboratory conditions, on the foliage of the species Quercus cerris L. Quercus petraea (Matt Liebl. and Quercus robur L. The experiment was established in the controlled environmental conditions, at the temperature of 25°C, photoperiod 14:10 (day: night and relative humidity 70%. The objective of the research was to determine the suitability of the study host plant species for gypsy moth development. The study results show that Gypsy moth caterpillars cultivated on Q. petraea foliage had a lower survival, higher number of moultings, longer preadult development and lower fecundity, which makes this species less suitable compared to the other two. Gypsy moth caterpillars cultivated on Q. cerris foliage had the highest survival degree the lowest number of moultings, the shortest preadult development and the highest fecundity, which makes this species the most favourable for gypsy moth development. Q. robur was between the former two species in this respect.

Population genetics of indigenous quercus robur L. populations and of derived half-sib families has implications for the reproductive management of the species

NARCIS (Netherlands)

Bakker, E.G.; Dam, van B.C.; Eeuwijk, van F.A.; Jacobsen, E.

2003-01-01

In the Netherlands indigenous Quercus robur L. populations are rare and have been maintained as patches in ancient woodland. For adequate conservation of these populations, information about genetic variation and population structure is necessary. in order to assess the genetic variation and

The taxonomic status of the Mexican oak Quercus undata (Fagaceae, Quercus, Section Quercus El estatus taxonómico del encino mexicano Quercus undata (Fagaceae, Quercus, Sección Quercus

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Jeffrey R. Bacon

2011-12-01

Full Text Available Quercus undata Trel. (Fagaceae, Quercus, Section Quercus has a complex taxonomic and nomenclatural history. Intensive sampling of oaks at the type locality of Q. undata Trel. in Durango, Mexico and evaluation of herbarium specimens and plants in the field indicate that Q. undata represents variation in Quercus chihuahuensis Trel. in white oak communities where introgressive hybridization among Q. chihuahuensis, Q. grisea Liebm., and a third white oak, Q. arizonica Sarg. made species identification difficult. Endlich's type specimen of Q. undata, as designated by Trelease, was apparently destroyed in bombing raids on Berlin during World War II, and we propose herein as lectotype the Trelease illustration of the type. An epitype is also designated in support of the lectotype, given that some features cannot be critically observed on the illustration. The long peduncles of the specimen illustrated by Trelease indicate a close relation to Q. chihuahuensis.Quercus undata Trel. (Fagaceae, Quercus, Section Quercus tiene una compleja historia taxonómica y de nomenclatura. Un muestreo intensivo de los encinos en la localidad tipo de Q. undata en Durango, México y análisis de ejemplares en herbario y en el campo indican que Q. undata representa variación en Q. chihuahuensis Trel. en los sitios donde la hibridación introgresiva entre Q. chihuahuensis, Q. grisea Liebm., y un tercer encino blanco, Q. arizonica Sarg., dificultan la identificación de especies. El ejemplar tipo designado por Trelease aparentemente fue destruido en el bombardeo de Berlín durante la Segunda Guerra Mundial, por lo que se propone como lectotipo a la ilustración del tipo en la obra de Trelease. Se designa también un epitipo dado que algunos rasgos no pueden ser críticamente observados en la ilustración. Los largos pedúnculos del espécimen ilustrado por Trelease indican la relación cercana a Q. chihuahuensis.

High rates of gene flow by pollen and seed in oak populations across Europe

NARCIS (Netherlands)

Gerber, S.; Chadoeuf, J.; Gugerli, F.; Lascoux, M.; Buiteveld, J.; Cottrell, J.; Dounavi, A.; Fineschi, S.; Forrest, L.; Fogelqvist, J.; Goicoechea, P.G.; Jensen, J.S.; Salvini, D.; Vendramin, G.G.; Kremer, A.

2014-01-01

Gene flow is a key factor in the evolution of species, influencing effective population size, hybridisation and local adaptation. We analysed local gene flow in eight stands of white oak (mostly Quercus petraea and Q. robur, but also Q. pubescens and Q. faginea) distributed across Europe. Adult

Responses of evergreen and deciduous Quercus species to enhanced ozone levels

International Nuclear Information System (INIS)

Calatayud, Vicent; Cervero, Julia; Calvo, Esperanza; Garcia-Breijo, Francisco-Jose; Reig-Arminana, Jose; Sanz, Maria Jose

2011-01-01

Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD 1.6 ) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. - Ozone tolerance overlapped with leaf traits in four Quercus species.

Responses of evergreen and deciduous Quercus species to enhanced ozone levels

Energy Technology Data Exchange (ETDEWEB)

Calatayud, Vicent, E-mail: calatayud_viclor@gva.e [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Cervero, Julia; Calvo, Esperanza [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Garcia-Breijo, Francisco-Jose [Laboratorio de Anatomia e Histologia Vegetal ' Julio Iranzo' , Jardin Botanico, Universitat de Valencia, c/Quart 80, 46008 Valencia (Spain); Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Reig-Arminana, Jose [Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Sanz, Maria Jose [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain)

2011-01-15

Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD{sub 1.6}) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. - Ozone tolerance overlapped with leaf traits in four Quercus species.

Effects of sodium chloride salinity on ecophysiological and biochemical parameters of oak seedlings (Quercus robur L.) from use of de-icing salts for winter road maintenance.

Science.gov (United States)

Laffray, Xavier; Alaoui-Sehmer, Laurence; Bourioug, Mohamed; Bourgeade, Pascale; Alaoui-Sossé, Badr; Aleya, Lotfi

2018-04-04

Salt is widely used to melt snow on roads especially in mountain regions. Whether as rock salt or aerosols, spread or sprayed over road surfaces, salt may result in increased salt concentrations in soils, which, in turn, affect natural vegetation, especially tree seedlings already subjected to various other types of abiotic stress. The authors investigated the effects of salt treatment-related stress on seedling growth and certain biochemical parameters in Quercus robur to determine ion concentrations in root tips. Seedlings growing in a quartz sand/vermiculite mixture were subjected to NaCl concentrations of 0, 50, or 100 mM for 5 weeks. The results showed that high NaCl concentrations caused a marked reduction in total leaf biomass 55 and 75% for 50 and 100 mM treatments, respectively, in dry weight of stems (84%) and roots (175%) for 100 mM treatment and modified root architecture, whereas no changes appeared in leaf number. A non-significant decrease in relative water content, with changes in ion balance was recorded. Comparison of stressed to control plants show an increase in sodium (3.5-8-fold), potassium (0.6-fold), and chloride (9.5-14-fold) concentrations in the root tips while the K + /Na + ratio decreased. In taproots, no significant biochemical differences were observed between the salt-treated and the control plants for acid invertase activity, reducing sugars, sucrose, or soluble protein contents. The significance of ion and sugar accumulations in relation to osmotic adjustment and the ability of oak seedlings to cope with salt stress are discussed.

The most significant fungi: Agents of wood decay in oak forests of Serbia

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Milijašević Tanja

2007-01-01

Full Text Available The most widely distributed oak species in Serbia are Q. petrea (sessile oak, Q. cerris (Turkey oak and Q. frainetto (Hungarian oak and Quercus robur (common oak, and lignicolous fungi are the major agents of wood decay in natural and coppice oak forests. In this research, 33 species of fungi were identified. Eleven species were described, among which the most significant are: Armillaria mellea, Fomes fomentarius, Hypoxylon deustum Laetiporus sulphureus, Lenzites quercina and Phellinus robustus. This paper presents the morphological characteristics of the most significant identified fungi, their distribution, host plants and significance.

Chloroplast DNA variation of oaks in western Central Europe and genetic consequences of human influences

NARCIS (Netherlands)

König, A.O.; Ziegenhagen, B.; Dam, van B.C.; Csaikl, U.M.; Coart, E.; Degen, B.; Burg, K.; Vries, de S.M.G.; Petit, R.J.

2002-01-01

Oak chloroplast DNA (cpDNA) variation was studied in a grid-based inventory in western Central Europe, including Belgium, The Netherlands, Luxembourg, Germany, the Czech Republic, and the northern parts of Upper and Lower Austria. A total of 2155 trees representing 426 populations of Quercus robur

Occurrence of Phytophthora plurivora and other Phytophthora species in oak forests of southern Poland and their association with site conditions and the health status of trees

Czech Academy of Sciences Publication Activity Database

Jankowiak, R.; Stepniewska, H.; Bilanski,, P.; Kolařík, Miroslav

2014-01-01

Roč. 59, č. 6 (2014), s. 531-542 ISSN 0015-5632 Institutional support: RVO:61388971 Keywords : DECLINING OAK * QUERCUS-ROBUR * ROOT-ROT Subject RIV: EE - Microbiology, Virology Impact factor: 1.000, year: 2014

Growth of Oregon white oak (Quercus garryana)

Science.gov (United States)

Peter J. Gould; Constance A. Harrington; Warren D. Devine

2011-01-01

Many land managers are interested in maintaining or restoring plant communities that contain Oregon white oak (OWO, Quercus garryana), yet there is relatively little information available about the species' growth rates and survival to guide management decisions. We used two studies to characterize growth (over multi-year periods and within...

Antioxidant Characterization of Oak Extracts Combining Spectrophotometric Assays and Chemometrics

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Boris M. Popović

2013-01-01

Full Text Available Antioxidant characteristics of leaves, twigs, and acorns from two Serbian oak species Quercus robur L. and Quercus petraea L. from Vojvodina province (northern Serbia were investigated. 80% ethanol (in water extracts were used for antiradical power (ARP determinations against DPPH•, NO•, and O2∙- radicals, ferric reducing antioxidant power (FRAP, total phenol, tannin, flavonoid, and proanthocyanidin contents. Permanganate reducing antioxidant capacity (PRAC was determined using water extracts. Beside, mentioned parameters, soluble proteins, lipid peroxidation (LP, pigments and proline contents were also determined. The data of different procedures were compared and analyzed by multivariate techniques (correlation matrix calculation and principal component analysis (PCA. PCA found that investigated organs of two different oak tree species possess similar antioxidant characteristics. The superior antioxidant characteristics showed oak leaves over twigs and acorns and seem to be promising source of antioxidants with possible use in industry and pharmacy.

Changes in carbon uptake and allocation patterns in Quercus robur seedlings in response to elevated CO2 and water stress: an evaluation with 13C labelling

International Nuclear Information System (INIS)

Vivin, P.; Guehl, J.M.

1997-01-01

A semi-closed (CO2)-C-13 labelling system (1.5% C-13) was used to assess both carbon uptake and allocation within pedunculate oak seedlings (Quercus robur L) grown under ambient (350 vpm) and elevated (700 vpm) atmospheric CO2 concentration ([CO2]) and in either well-watered or droughted conditions. Pulse-chase C-13 labelling data highlighted the direct positive effect of elevated CO2 on photosynthetic carbon acquisition. Consequently, in well-watered conditions, CO2-enriched plants produced 1.52 times more biomass (dry mass at harvest) and 1.33 times more dry root matter (coarse plus fine roots) over the 22-week growing period than plants grown under ambient [CO2]. The root/shoot biomass ratio was decreased both by drought and [CO2], despite lower N concentrations in CO2-enriched plants. However, both long-term and short-term C allocation to fine roots were not altered by CO2, and relative specific allocation (RSA), a parameter expressing sink strength, was hip her in all plant organs under 700 vpm compared to 350 vpm. Results showed that C availability for growth and metabolic processes was greater in fine roots of oaks grown under an elevated CO2 atmosphere irrespective of soil water availability [fr

Development of Molecular Markers for Determining Continental Origin of Wood from White Oaks (Quercus L. sect. Quercus.

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Hilke Schroeder

Full Text Available To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica as a reference, we identified 861 variant sites (672 single nucleotide polymorphisms (SNPs; 189 insertion/deletion (indel polymorphism from representative species of three continents (Q. mongolica from Asia; Q. petraea and Q. robur from Europe; Q. alba from North America, and we identified additional chloroplast polymorphisms in pools of 20 individuals each from Q. mongolica (789 variant sites and Q. robur (346 variant sites. Genome sequences were screened for indels to develop markers that identify continental origin of oak species, and that can be easily evaluated using a variety of detection methods. We identified five indels and one SNP that reliably identify continent-of-origin, based on evaluations of up to 1078 individuals representing 13 white oak species and three continents. Due to the size of length polymorphisms revealed, this marker set can be visualized using capillary electrophoresis or high resolution gel (acrylamide or agarose electrophoresis. With these markers, we provide the wood trading market with an instrument to comply with the U.S. and European laws that require timber companies to avoid the trade of illegally harvested timber.

Coast live oak, Quercus agrifolia, susceptibility and response to goldspotted oak borer, Agrilus auroguttatus, injury in southern California

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Tom W. Coleman; Nancy E. Grulke; Miles Daly; Cesar Godinez; Susan L. Schilling; Philip J. Riggan; Steven J. Seybold

2011-01-01

Oak mortality is often associated with a complex of decline factors. We describe the morphological and physiological responses of coast live oak, Quercus agrifolia Née, in California to an invasive insect, the goldspotted oak borer (GSOB), Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and evaluate drought as a...

( Quercus spp. ) using random amplified polymorphic DNA (RAPD)

African Journals Online (AJOL)

Quercus is one of the most important woody genera of the Northern hemisphere and considered as one of the main forest tree species in Iran. In this study, genetic relationships in the genus Quercus, using random amplified polymorphic DNA (RAPD) was examined. Five species, including: Quercus robur, Quercus ...

Sessile oak (Quercus petraea agg. Ehrendorfer 1967) rare ...

African Journals Online (AJOL)

Sessile oak ( Quercus petraea agg. Ehrendorfer 1967) genetic variability in Serbia was estimated applying cpDNA universal primer pairs. Five different haplotypes were detected in the analyzed sample material from populations in Serbia. The areas in West and Southwest Serbia, with all their specificities, represent an ...

Evaluation of extractive content in Albanian white oak ( Quercus ...

African Journals Online (AJOL)

, have an important impact on wood properties and its utilization. The study was carried on extractives content of white oak (Quercus petraea Liebl). Eighteen sawdust samples were taken from cuts in six different heights of three trees.

El estatus taxonómico del encino mexicano Quercus undata (Fagaceae, Quercus, Sección Quercus)

OpenAIRE

Bacon, Jeffrey R.; Dávila-Aranda, Patricia Dolores; Spellenberg, Richard; González-Elizondo, M. Socorro

2011-01-01

Quercus undata Trel. (Fagaceae, Quercus, Section Quercus) has a complex taxonomic and nomenclatural history. Intensive sampling of oaks at the type locality of Q. undata Trel. in Durango, Mexico and evaluation of herbarium specimens and plants in the field indicate that Q. undata represents variation in Quercus chihuahuensis Trel. in white oak communities where introgressive hybridization among Q. chihuahuensis, Q. grisea Liebm., and a third white oak, Q. arizonica Sarg. made species identifi...

Genetic diversity and population structure of Raffaelea quercus-mongolicae, a fungus associated with oak mortality in South Korea

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M. -S. Kim; P. A. Hohenlohe; K. -H. Kim; S. -T. Seo; Ned Klopfenstein

2016-01-01

Raffaelea quercus-mongolicae is a fungus associated with oak wilt and deemed to cause extensive oak mortality in South Korea. Since the discovery of this fungus on a dead Mongolian oak (Quercus mongolica) in 2004, the mortality continued to spread southwards in South Korea. Despite continued expansion of the disease and associated significant impacts on forest...

Draft genome sequence of the fungus associated with oak-wilt mortality in South Korea, Raffaelea quercus-mongolicae KACC44405

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Jongbum Jeon; Ki-Tae Kim; Hyeunjeong Song; Gir-Won Lee; Kyeongchae Cheong; Hyunbin Kim; Gobong Choi; Yong-Hwan Lee; Jane E. Stewart; Ned B. Klopfenstein; Mee-Sook Kim

2017-01-01

The fungus Raffaelea quercus-mongolicae is the causal agent of Korean oak wilt, a disease associated with mass mortality of oak trees (e.g., Quercus spp.). The fungus is vectored and dispersed by the ambrosia beetle, Platypus koryoensis. Here, we present the 27.0-Mb draft genome sequence of R. quercus-mongolicae strain KACC44405.

Growth overcompensation against O3 exposure in two Japanese oak species, Quercus mongolica var. crispula and Quercus serrata, grown under elevated CO2

International Nuclear Information System (INIS)

Kitao, Mitsutoshi; Komatsu, Masabumi; Yazaki, Kenichi; Kitaoka, Satoshi; Tobita, Hiroyuki

2015-01-01

To assess the effects of elevated concentrations of carbon dioxide (CO 2 ) and ozone (O 3 ) on the growth of two mid-successional oak species native to East Asia, Quercus mongolica var. crispula and Quercus serrata, we measured gas exchange and biomass allocation in seedlings (initially 1-year-old) grown under combinations of elevated CO 2 (550 μmol mol −1 ) and O 3 (twice-ambient) for two growing seasons in an open-field experiment in which root growth was not limited. Both the oak species showed a significant growth enhancement under the combination of elevated CO 2 and O 3 (indicated by total dry mass; over twice of ambient-grown plants, p < .05), which probably resulted from a preferable biomass partitioning into leaves induced by O 3 and a predominant enhancement of photosynthesis under elevated CO 2 . Such an over-compensative response in the two Japanese oak species resulted in greater plant growth under the combination of elevated CO 2 and O 3 than elevated CO 2 alone. - Highlights: • Quercus mongolica var. crispula and Quercus serrata were grown under elevated CO 2 and O 3 . • O 3 induced a preferable biomass allocation into leaves. • Photosynthesis was predominantly enhanced under elevated CO 2 exceeding O 3 impacts. • Combination of elevated CO 2 and O 3 enhanced the growth of two oak species. - O 3 -induced carbon allocation into leaves and CO 2 -enhanced photosynthesis result in a significant growth enhancement in Japanese oak species under the combination of gases.

Microevolution of European temperate oaks in response to environmental changes.

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Kremer, Antoine

2016-01-01

This review reconstructs microevolutionary processes that allowed long-lived species as temperate oaks (Quercus petraea and Q. robur) to cope with climate change since the last glacial maximum, by assembling insights from complementary synchronic and allochronic approaches. Paleobotanical and genetic investigations show that oaks migrated at larger velocities than expected, thanks to long-distance rare events and most likely human interferences. Hybridization was a key mechanism accelerating migration and enhancing species succession. Common garden experiments and genome wide association studies demonstrated that diversifying selection across large environmental gradients contributed to rapid local adaptation. Finally the review explores how lessons taken from past evolutionary scenarios may help to predict future responses of oaks to ongoing climate change. Copyright © 2016. Published by Elsevier SAS.

Adaptive genetic variability and differentiation of Croatian and Austrian Quercus robur L. populations at a drought prone field trial

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Saša Bogdan

2017-07-01

Full Text Available Provenance trials, where populations of different geographical origin are tested in a common environment (common garden test, are a tool suited to allow the study of intraspecific adaptive genetic variation. Research of pedunculate oak (Quercus robur L. adaptive genetic variability through analyses of populations in common garden tests has a long tradition. However, pedunculated oak populations originating south-eastern from the Alps have been scarcely studied in this way. This study addresses the adaptive genetic variability and differentiation of pedunculate oak populations originating from Austria and Croatia in a provenance/progeny field trial. Studied plants were six years old and were growing at the trial for three years. After two years of unusually low precipitations height and survival were analysed. The total mean height of all plants in the trial was 137.8 cm and ranged from 123.0 cm to 151.8 cm. The overall mean survival rate was rather high (0.85. Mean population survival ranged from 0.64 to 0.94. Individual narrow-sense heritabilities (hi2, family mean heritabilities (hf2, the coefficients of additive genetic variation (CVA and quantitative genetic differentiation coefficients (QST were calculated. A multivariate regression tree (MRT analysis was used to determine the pattern of genetic differentiation of the populations. Individual heritabilities for height ranged between 0.00 and 0.39. Family mean heritabilities for height were rather low in most populations as well (<0.5. Family mean heritabilities for survival were higher than for height (ranging between 0.00 and 0.77. Calculated QST coefficients (0.25 for height and 0.14 for survival indicated between-population genetic differentiation. The populations were separated into two clusters by MRT analysis regarding a climatic variable, namely Hargreaves’ reference evapotranspiration. Populations originating from comparatively more humid habitats were grouped in the first

Impact of stereoide fungi on decomposition of oak wood and possibility of its protection

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Mirić Milenko

2005-01-01

Full Text Available Four stereoide fungi, causers of decay of oak wood, have been investigated as follows: Stereum hirsutum, Chondrostereum purpureum, Stereum rugosum and Xylobolus frustulatus. The field tests have been undertaken in order to determine the influence of the stereoide fungi on the wood of Sessile oak (Quercus petraea and Austrian oak (Quercus robur. Artificial inoculations with mycelia have been provoked in vital standing trees, as well as in laying trunks. The appearance of dying back symptoms, the rate of mycelia spread through the stem, speed of wound callusing and appearance of fruit bodies or decay symptoms, have been observed. The protection possibility of trunks has been tested as well by using preservatives based on chromo-cupric boron salts, dichlorfluanide and chlorinepyriphos, cupric naphtenates, as well as with antiseptic paste. Microscopically analysis of attacked oak wood has been performed by utilizing of scanning electron (SEM and standard optical microscope providing normal, fluorescence, polarized and UV light, so that anatomical changes of the wood structure elements influenced by fungal activity have been noted.

The influence of tree age and microhabitat quality on the occurrence of crustose lichens associated with old oaks

OpenAIRE

Ranius, Thomas; Johansson, Per; Berg, Niclas; Niklasson, Mats

2008-01-01

Questions: How do tree age, microhabitat characteristics and epiphytic competitors affect the occurrence of crustose lichens associated with old oaks? How do microhabitat characteristics and microclimate affect the cover of competitors (bryophytes and macrolichens)? How do microhabitat characteristics cor¬relate with microclimatic variables? Location: Southeast Sweden. Methods: Eight crustose lichen species were surveyed on 165 Quercus robur trees, 17-478 years old, at three study sit...

Changes in the IgE-reacting protein profiles of Acer negundo, Platanus x acerifolia and Quercus robur pollen in response to ozone treatment.

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Ribeiro, Helena; Duque, Laura; Sousa, Raquel; Cruz, Ana; Gomes, Carlos; da Silva, Joaquim Esteves; Abreu, Ilda

2014-01-01

This study aims to investigate the effects of O3 in protein content and immunoglobulin E (IgE)-binding profiles of Acer negundo, Platanus x acerifolia and Quercus robur pollen. Pollen was exposed to O3 in an environmental chamber, at half, equal and four times the limit value for the human health protection in Europe. Pollen total soluble protein was determined with Coomassie Protein Assay Reagent, and the antigenic and allergenic properties were investigated by SDS-PAGE and immunological techniques using patients' sera. O3 exposure affected total soluble protein content and some protein species within the SDS-PAGE protein profiles. Most of the sera revealed increased IgE reactivity to proteins of A. negundo and Q. robur pollen exposed to the pollutant compared with the non-exposed one, while the opposite was observed in P. x acerifolia pollen. So, the modifications seem to be species dependent, but do not necessarily imply that increase allergenicity would occur in atopic individuals.

In vitro propagation of northern red oak (Quercus rubra L.)

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G. Vengadesan; Paula M. Pijut

2009-01-01

In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 µM 6-benzylaminopurine (BA), 0.45 ...

Regeneration of red oak (Quercus rubra L.) using shelterwood systems: Ecophysiology, silviculture and management recommendations

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Daniel C. Dey; William C. parker

1996-01-01

There is considerable interest in developing relaible methods for regenerating red oak (Quercus rubra) in Ontario. Traditional silviculture methods have not been successful in maintaining the curent levels of oak growing stock. In this paper, we review the ecology, physiology and reproductive biology of red oak. This discussion stresses the...

Ozone risk assessment in three oak species as affected by soil water availability.

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Hoshika, Yasutomo; Moura, Barbara; Paoletti, Elena

2018-03-01

To derive ozone (O 3 ) dose-response relationships for three European oak species (Quercus ilex, Quercus pubescens, and Quercus robur) under a range of soil water availability, an experiment was carried out with 2-year-old potted seedlings exposed to three levels of water availability in the soil and three levels of O 3 pollution for one growing season in an ozone free-air controlled exposure (FACE) facility. Total biomass losses were estimated relative to a hypothetical clean air at the pre-industrial age, i.e., at 10 ppb as daily average (M24). A stomatal conductance model was parameterized with inputs from the three species for calculating the stomatal O 3 flux. Exposure-based (M24, W126, and AOT40) and flux-based (phytotoxic O 3 dose (POD) 0-3 ) dose-response relationships were estimated and critical levels (CL) were calculated for a 5% decline of total biomass. Results show that water availability can significantly affect O 3 risk assessment. In fact, dose-response relationships calculated per individual species at each water availability level resulted in very different CLs and best metrics. In a simplified approach where species were aggregated on the basis of their O 3 sensitivity, the best metric was POD 0.5 , with a CL of 6.8 mmol m -2 for the less O 3 -sensitive species Q. ilex and Q. pubescens and of 3.5 mmol m -2 for the more O 3 -sensitive species Q. robur. The performance of POD 0 , however, was very similar to that of POD 0.5 , and thus a CL of 6.9 mmol m -2 POD 0 and 3.6 mmol m -2 POD 0 for the less and more O 3 -sensitive oak species may be also recommended. These CLs can be applied to oak ecosystems at variable water availability in the soil. We conclude that POD y is able to reconcile the effects of O 3 and soil water availability on species-specific oak productivity.

Interspecific variation in functional traits of oak seedlings (Quercus ilex, Quercus trojana, Quercus virgiliana) grown under artificial drought and fire conditions.

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Chiatante, D; Tognetti, R; Scippa, G S; Congiu, T; Baesso, B; Terzaghi, M; Montagnoli, A

2015-07-01

To face summer drought and wildfire in Mediterranean-type ecosystems, plants adopt different strategies that involve considerable rearrangements of biomass allocation and physiological activity. This paper analyses morphological and physiological traits in seedlings of three oak species (Quercus ilex, Quercus trojana and Quercus virgiliana) co-occurring under natural conditions. The aim of this study was to evaluate species-specific characteristics and the response of these oak seedlings to drought stress and fire treatment. Seedlings were kept in a growth chamber that mimicked natural environmental conditions. All three species showed a good degree of tolerance to drought and fire treatments. Differences in specific biomass allocation patterns and physiological traits resulted in phenotypic differences between species. In Q. ilex, drought tolerance depended upon adjustment of the allocation pattern. Q. trojana seedlings undergoing mild to severe drought presented a higher photosystem II (PSII) efficiency than control seedlings. Moreover, Q. trojana showed a very large root system, which corresponded to higher soil area exploitation, and bigger leaf midrib vascular bundles than the other two species. Morphological and physiological performances indicated Q. trojana as the most tolerant to drought and fire. These characteristics contribute to a high recruitment potential of Q. trojana seedlings, which might be the reason for the dominance of this species under natural conditions. Drought increase as a result of climate change is expected to favour Q. trojana, leading to an increase in its spatial distribution.

Microsatellite Primer Development for Post Oak, Quercus stellata (Fagaceae

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Warren B. Chatwin

2014-10-01

Full Text Available Premise of the study: The American Cross Timbers forest ecosystem runs from southeastern Kansas to Central Texas and is primarily composed of post oak (Quercus stellata. This old-growth forest currently occupies only about 2% of its ancestral range. To facilitate genetic research on this species, we developed microsatellite primers specific to post oak from reduced genomic libraries. Methods and Results: Two Q. stellata individuals, sampled from the northern and southern range of the post oak forest, were subject to genomic reduction and 454 pyrosequencing. Bioinformatic analysis identified putative microsatellites from which 12 polymorphic primer sets were screened on three populations. The number of alleles observed ranged from five to 20 across all populations, while observed and expected heterozygosity values ranged from 0.05 to 0.833 and 0.236 to 0.893, respectively, within individual populations. Conclusions: We report the development of microsatellite markers, specific to post oak, to aid the study of genetic diversity and population structure of extant forest remnants.

Structure of herbivore communities in two oak (Quercus spp.) hybrid zones.

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Boecklen, William J; Spellenberg, Richard

1990-11-01

We examined patterns of density and species diversity for leaf-mining Lepidopterans and gall-forming Hymenopterans in two oak (Quercus spp.) hybrid zones: Quercus depressipes x Q. rugosa and Q. emoryi x Q. coccolobifolia. In both species complexes, hybrid hosts typically supported significantly lower densities and species diversity of parasites than did parental types. This contradicts the findings of Whitham (1989) that suggested that hybrid hosts may act as parasite sinks both in ecological and evolutionary time. We discuss features of hybrid zones that are likely to influence patterns of herbivory.

Uptake of Nitrogen Dioxide by Quercus robur - is There a Compensation Point?

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Thielmann, A.; Chaparro, G.; Kuhn, U.; Dindorf, T.; Lehmann, L.; Kortner, M.; Tritsch, C.; Kesselmeier, J.; Meixner, F. X.

2003-12-01

Within the German Atmospheric-Research-Program 2000, the project ECHO (Emission and CHemical Transformation of Biogenic Volatile Organic Compounds) has been carried out in a mixed forest stand during the summer of 2002. The contribution of the Max Planck Institute for Chemistry was the complete characterization of the NOx-flux within the forest, including (a) the quantification of the biogenic NO-release from forest soils, (b) the measurement of the vertical distribution of NOx within and above the canopy and (c) the turbulent transport within and above the forest. The profile measurements allow to identify the participating processes: soil NO emission and subsequent titration of emitted NO by ozone, advection of highly polluted air masses to the site and the uptake of nitrogen dioxide within the crown area. The latter, i.e. the role of vegetation in the NOx-budget within a particular ecosystem is still a matter in controversy, which translates into considerable uncertainties in the global NOx-budget. To assess this issue, dynamic cuvette measurements were performed on a Quercus robur branch. The concurrent measurement of plant physiological (leaf temperature, stomatal conductance, transpiration and photosynthesis/respiration) and ambient parameters (radiation, ambient NOx mixing ratios) allows to put the exchange rate into context. The question whether a compensation point may be identified will especially be addressed.

INFLUENCE OF TORREFACTION ON SOME CHEMICAL AND ENERGY PROPERTIES OF MARITIME PINE AND PEDUNCULATE OAK

OpenAIRE

Floran Pierre; Giana Almeida; José Otavio Brito; Patrick Perré

2011-01-01

This study investigated the influence of heat treatment on the chemical composition and energy properties of maritime pine (Pinus pinaster) and pedunculate oak (Quercus robur). Samples were treated in a new experimental device at 220, 250, or 280 degrees C for 1 or 5 hours. Chemical and energy analyses were performed using standard methods. Our results clearly demonstrated an increased degradation of the material due to the combined effects of temperature and treatment duration. This mass los...

Water metabolism of leaves of Quercus robur in antierosion stands in the south of its range

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V. P. Bessonova

2016-10-01

Full Text Available We have investigated the main parameters of water exchange in leaves of Quercus robur L. which grow on the south-facing slope of the Viyskoviy ravine in a variety of water supply conditions. We established that the greatest intensity of transpiration of leaves of Q. robur occurred in the forest vegetation conditions of SG2, the smallest in SG1–0. In all study periods the largest amplitude of daily fluctuations in intensity of transpiration occurred in leaves of plants along the talweg, at other test sites the limits were much lower. The highest rates of transpiration were in September, which is connected with the high temperatures and lower relative air humidity compared with the days of measurement in July and May. We established that at the beginning of the growing season there was no difference in the total amount of water in the leaves of the trees that grow on the middle and upper parts of the slope, but that it was greater in plants along the talweg. In the following months the difference between the water content in the leaves of trees along the talweg and upper third of the slope increased. The leaves of trees that grow in the poorest conditions of water supply were characterized by the highest water-holding capacity, which is coordinated with their containing the highest content of hydrophilic colloids. The values for water deficit in May and in July fell within the maximum fluctuations for the species studied, but in early September they exceeded the maximum value in the leaves of trees on the upper third of the slope.

Effects of the goldspotted oak borer, Agrilus auroguttatus, on the health of coast live oak, Quercus agrifolia, in southern California before and after treatment with two systemic insecticides

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Yigen Chen; Mary L. Flint; Tom W. Coleman; Joseph J. Doccola; Donald M. Grosman; David L. Wood; Steven J. Seybold

2015-01-01

The invasive goldspotted oak borer, Agrilus auroguttatus (Coleoptera: Buprestidae), is threatening the health and survival of oak trees in San Diego County, California (Flint and others 2013). The primary oak species colonized and killed in this area include coast live oak (Quercus agrifolia), California black oak (...

Growth overcompensation against O3 exposure in two Japanese oak species, Quercus mongolica var. crispula and Quercus serrata, grown under elevated CO2.

Science.gov (United States)

Kitao, Mitsutoshi; Komatsu, Masabumi; Yazaki, Kenichi; Kitaoka, Satoshi; Tobita, Hiroyuki

2015-11-01

To assess the effects of elevated concentrations of carbon dioxide (CO2) and ozone (O3) on the growth of two mid-successional oak species native to East Asia, Quercus mongolica var. crispula and Quercus serrata, we measured gas exchange and biomass allocation in seedlings (initially 1-year-old) grown under combinations of elevated CO2 (550 μmol mol(-1)) and O3 (twice-ambient) for two growing seasons in an open-field experiment in which root growth was not limited. Both the oak species showed a significant growth enhancement under the combination of elevated CO2 and O3 (indicated by total dry mass; over twice of ambient-grown plants, p CO2. Such an over-compensative response in the two Japanese oak species resulted in greater plant growth under the combination of elevated CO2 and O3 than elevated CO2 alone. Copyright © 2015 Elsevier Ltd. All rights reserved.

The phenolic extractives in southern red oak (Quercus falcata Michx. var. falcata)

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Seiji Ohara; Richard W. Hemingway

1989-01-01

The bark of southern red oak (Quercus falcala Michx. var. falcala) is a rich source of quercitrin (quercetin-3-rhamnoside). It contains only low concentrations of (+)-catechin and no significant amounts of epicatechin or gallocatechin. The three major dimeric proanthocyanidins present are epicatechin-(4β→8)-...

Pathogenicity of Phytophthora isolates originating from several woody hosts in Bulgaria and Poland

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Lyubenova Aneta B.

2016-09-01

Full Text Available Our aim was to examine the virulence of eight Phytophthora isolates belonging to three species (Phytophthora cryptogea, Phytophthora plurivora and Phytophthora quercina obtained from diverse European ecosystems (in Bulgaria, Poland and Germany towards three forest tree hosts – English oak (Quercus robur L., Turkey oak (Quercus cerris L. and European beech (Fagus sylvatica L..

Changes in the Chemical Composition of Plum Distillate During Maturation with Oak Chips under Different Conditions.

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Balcerek, Maria; Pielech-Przybylska, Katarzyna; Dziekońska-Kubczak, Urszula; Patelski, Piotr; Strąk, Ewelina

2017-09-01

This study investigates the effect of ageing on the qualitative and quantitative composition of plum distillate in contact with oak wood chips. Maturation was performed with lightly toasted French oak ( Quercus sessiflora and Quercus robur ) chips or oak chips made from fragments of empty barrels that had been used for ageing cognac. The effects of oak chip dose, process temperature, ageing system (static or circulatory) and ultrasound treatment were assessed. Maturation of plum distillate samples with oak chips resulted in higher levels of extractable organics (including tannins) and colour changes, which were correlated with the type and dose of oak chips, and the conditions of maturation. The content of sugars such as glucose, xylose and arabinose also increased, depending on the conditions and type of oak chips. Degradation of lignin resulted in liberation of sinapaldehyde, syringaldehyde, coniferaldehyde and vanillin, with intensities depending on the applied parameters. In terms of volatiles, decreases in the concentration of higher alcohols and aliphatic aldehydes were observed in the majority of maturation experiments, while concentrations of furanic aldehydes increased depending on the type and dose of oak chips, as well as on the conditions of maturation. The quantities of esters such as ethyl acetate decreased in the majority of experimental variants, whereas concentrations of ethyl caproate, ethyl caprylate and ethyl caprate increased gradually. Some phenols and lactones were detected in all matured samples, with the lowest levels found in the samples aged with oak chips made from cognac barrels.

Artificial regeneration of major oak (Quercus) species in the eastern United States - a review of the literature

Science.gov (United States)

Daniel C. Dey; Douglass Jacobs; Ken McNabb; Gary W. Miller; V. Baldwin; G. Foster

2008-01-01

Although natural regeneration is often the best method for establishing new oak (Quercus spp.) stands, there are increasingly more situations in which high potential for oak regeneration failure dictates the use of artificial regeneration including direct seeding and planting seedlings. Additionally, afforestation planting programs frequently...

Macromycetes of oak-lime-hornbeam woods in the Niepołomice Forest near Kraków (S Poland - monitoring studies

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Władysława Wojewoda

2014-08-01

Full Text Available In the years 1994-1996 studies on macromycetes of the Niepołomice Forest near Kraków were made in four plots designated in deciduous forests (Tilio-Carpinetum stachyetosum with a population of Carpinus betulus, Quercus robur and Tilia cordata (the size of each plot was 1000 m2. The observations were made through an international project "Mycological monitoring in European oak forests". As many as 274 species were recorded, including 234 saprobic, 33 mycorrhizal, and 7 parasitic fungi. Moreover, 15 species of fungi are connected with oak, 24 species of fungi are threatened, and 16 species are new to Poland.

Phenolic compounds and sensorial characterization of wines aged with alternative to barrel products made of Spanish oak wood (Quercus pyrenaica Willd.).

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Gallego, L; Del Alamo, M; Nevares, I; Fernández, J A; Fernández de Simón, B; Cadahía, E

2012-04-01

Wood of Quercus pyrenaica has suitable properties for the wine ageing process. However, the forest available for the barrel making from this particular type of tree is very limited. Nevertheless, it is highly advisable to use this kind of wood in order to manufacture alternative oak products. This study presents the results of ageing the same red wine using different pieces of wood (chips and staves) of Spanish oak (Q. pyrenaica), American oak (Quercus alba) and French oak (Quercus petraea) in conjunction with small, controlled amounts of oxygen. In addition, the phenolic parameters, colour and sensory analysis point out that wines aged with Q. pyrenaica pieces have similar enological characteristics to those aged with American or French oak pieces of wood (chips and staves). Furthermore, the total oxygen consumed and its relation with sensory properties also has been studied in this article in order to know how the oxygen behaves in these processes. Besides, it is going to put forward the fact that chips and staves from Q. pyrenaica oak are suitable for the ageing of red wines and better considered than American or French ones, showing higher aromatic intensity, complexity, woody, balsamic and cocoa. Finally, the tasters valued highly the wines with staves, pointing out its flavour and roundness in mouth.

Influence of Soil Type and Drainage on Growth of Swamp Chestnut Oak (Quercus Michauxii Nutt.) Seedlings

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Donald D. Hook

1969-01-01

Swamp chestnut oak (Quercus michauxii Nutt.) seedlings were grown for 2 years in five soil types in drained and undrained pots. First-year height growth was related to soil type and pot drainage, but second-year height growth was related only to soil type. Results suggest that swamp chestnut oak is site-sensitive. But slow growth, a maximum of 2...

Changes in the Chemical Composition of Plum Distillate During Maturation with Oak Chips under Different Conditions

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Maria Balcerek

2017-01-01

Full Text Available This study investigates the eff ect of ageing on the qualitative and quantitative composition of plum distillate in contact with oak wood chips. Maturation was performed with lightly toasted French oak (Quercus sessifl ora and Quercus robur chips or oak chips made from fragments of empty barrels that had been used for ageing cognac. The eff ects of oak chip dose, process temperature, ageing system (static or circulatory and ultrasound treatment were assessed. Maturation of plum distillate samples with oak chips resulted in higher levels of extractable organics (including tannins and colour changes, which were correlated with the type and dose of oak chips, and the conditions of maturation. The content of sugars such as glucose, xylose and arabinose also increased, depending on the conditions and type of oak chips. Degradation of lignin resulted in liberation of sinapaldehyde, syringaldehyde, coniferaldehyde and vanillin, with intensities depending on the applied parameters. In terms of volatiles, decreases in the concentration of higher alcohols and aliphatic aldehydes were observed in the majority of maturation experiments, while concentrations of furanic aldehydes increased depending on the type and dose of oak chips, as well as on the conditions of maturation. The quantities of esters such as ethyl acetate decreased in the majority of experimental variants, whereas concentrations of ethyl caproate, ethyl caprylate and ethyl caprate increased gradually. Some phenols and lactones were detected in all matured samples, with the lowest levels found in the samples aged with oak chips made from cognac barrels.

Foliar nutrients explain goldspotted oak borer, Agrilus auroguttatus, adult feeding preference among four California oak species

Science.gov (United States)

Yigen Chen; Tom. W. Coleman; Michael. I. Jones; Mary. L. Flint; Steven. J. Seybold

2013-01-01

Adults of the invasive goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), consumed foliar weight in no-choice feeding tests of, in descending order, California black oak Quercus kelloggii Newb., Engelmann oak, Quercus engelmannii Greene, coast live oak, Quercus...

Wood anatomical parameters of lowland European oak and Scots pine as proxies for climate reconstructions

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Balanzategui, Daniel; Heußner, Karl-Uwe; Wazny, Tomasz; Helle, Gerd; Heinrich, Ingo

2017-04-01

Tree-ring based temperature reconstructions from the temperate lowlands worldwide are largely missing due to diffuse climate signals so far found in tree-ring widths. This motivated us to concentrate our efforts on the wood anatomies of two common European tree species, the European oak (Quercus robur) and Scots pine (Pinus sylvestris). We combined core samples of living trees with archaeological wood from northern Germany and Poland. We measured approx. 46,000 earlywood oak vessels of 34 trees covering the period AD 1500 to 2016 and approx. 7.5 million pine tracheid cells of 41 trees covering the period AD 1300 to 2010. First climate growth analyses indicate that both oak earlywood vessel and pine tracheid parameters contain climate signals which are different and more significant than those found in tree-ring widths. Preliminary results will be presented and discussed at EGU for the first time.

In vitro and in vivo assessment of anti-hyperglycemic and antioxidant effects of Oak leaves (Quercus convallata and Quercus arizonica) infusions and fermented beverages.

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Gamboa-Gómez, Claudia I; Simental-Mendía, Luis E; González-Laredo, Rubén F; Alcantar-Orozco, Esteban J; Monserrat-Juarez, Victor H; Ramírez-España, Julio C; Gallegos-Infante, Jose Alberto; Moreno-Jiménez, Martha R; Rocha-Guzmán, Nuria E

2017-12-01

The aim of this study was to evaluate the anti-hyperglycemic and antioxidant effects of oak leaves infusions and fermented beverages from Quercus convallata and Q. arizonica in vitro and in vivo. Female C57BL/6 mice fed with high saturated fat and fructose diet-induced obesity were treated with oak leaves beverages (200 μL/per day equivalent to 15mg of lyophilized sample/Kg of body weight for infusions and 31mg of lyophilized sample/Kg of body weight for fermented beverages) for 3months and an oral glucose tolerance test (OGTT) was performed. Blood plasma was obtained for determination of glucose, lipid profile, and oxidative stress markers (ABTS, nitric oxide, and ORAC assays). Insulin resistance was estimated using the product of triglycerides and glucose (TyG). Oak leaves infusions and fermented beverages exhibited exerted inhibition of α-amylase (8-15% and 5-9%, respectively) and α-glucosidase (98% and 99%, respectively) enzymes. After OGTT, the groups treated with either oak leaves infusions or fermented beverages showed lower glucose levels compared with the obesity control group (18%) and a similar glucose tolerance to healthy control group. On long-term evaluation, intervention groups showed a significant reduction in fasting glucose concentrations (41-50% for oak leaves infusions and 52-66% for fermented beverages) and TyG index (4.2-4.6% for oak leaves infusions and 5.9-7.5% for fermented beverages) compared with the obese control group. Oak leaves infusions and fermented beverages had antioxidant potential in vitro and scavenging activity for radicals such as peroxyl and peroxynitrite anions. Our results suggest anti-hyperglycemic and antioxidant effects of beverages prepared with leaves of Quercus species in vitro and in vivo. Copyright © 2017 Elsevier Ltd. All rights reserved.

Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

DEFF Research Database (Denmark)

Van Meeningen, Ylva; Schurgers, Guy; Rinnan, Riikka

2017-01-01

and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light......, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances...... be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or temperature dependencies for individual compounds across species. Light is an important environmental factor controlling biogenic...

Influence of overstory density on ecophysiology of red oak (Quercus rubra) and sugar maple (Acer saccharum) seedlings in central Ontario shelterwoods

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William C. Parker; Daniel C. Dey

2008-01-01

A field experiment was established in a secondgrowth hardwood forest dominated by red oak (Quercus rubra L.) to examine the effects of shelterwood overstory density on leaf gas exchange and seedling water status of planted red oak, naturally regenerated red oak and sugar maple (Acer saccharum Marsh.) seedlings during the first...

Climate change impact on a mixed lowland oak stand in Serbia

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Dejan Stojanović

2015-12-01

Full Text Available Climatic changes and bad environmental conditions may lead to forests vitality loss and even mortality. This is the reason why increased sanitary felling operations were performed in mixed oak forests in northern Serbia in 2013 in order to solve the severe dieback which affected some Pedunculate oak (Quercus robur L. and Turkey oak (Quercus cerris L. stands, after the very dry years 2011 and 2012.Dendrochronological techniques were applied to both these oak species collected in a stand, to examine the impact of temperature, precipitation and ground water level on forest growth and investigate the potential causes of the dieback.Differences in tree-ring patterns between surviving and dead trees were not significant according to t-value (from 5.68 to 14.20 and Gleichläufigkeit coefficient (from 76% to 82%, this meaning no distinctive responses of the two ecologically different oak species. As for radial increment, pedunculate and Turkey oak trees showed a similar response to environmental variables in this mixed stand. The Simple Pearson’s correlation analysis, which was conducted, showed that among three basic environmental variables (the mean monthly air temperature, the monthly sum of precipitation and the mean monthly water level, proxy of ground water level, the water level of Danube river in May and the temperature in April were statistically related to the growth of the four tree groups: (i pedunculate oak vital, (ii pedunculate oak dead, (iii Turkey oak vital and (iv Turkey oak dead trees, for the period 1961-2010 (p<0.05, n=60. Similar phenomena had already been observed in the Sava River basin for the growth of pure pedunculate oak forests. The long-term decline of the Danube River water level may be related to climate variations and to the changes of water management, river bed, as well as land-use. Together with the increase of temperature, this decline of the water level, and its potential unavailability in the soil, represents a

Changes in the dynamics of foliar N metabolites in oak saplings by drought and air warming depend on species and soil type.

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Bin Hu

Full Text Available Climate change poses direct or indirect influences on physiological mechanisms in plants. In particular, long living plants like trees have to cope with the predicted climate changes (i.e. drought and air warming during their life span. The present study aimed to quantify the consequences of simulated climate change for foliar N metabolites over a drought-rewetting-drought course. Saplings of three Central European oak species (i.e. Quercus robur, Q. petraea, Q. pubescens were tested on two different soil types (i.e. acidic and calcareous. Consecutive drought periods increased foliar amino acid-N and soluble protein-N concentrations at the expense of structural N in all three oak species. In addition, transient effects on foliar metabolite dynamics were observed over the drought-rewetting-drought course. The lowest levels of foliar soluble protein-N, amino acid-N and potassium cation with a minor response to drought and air warming were found in the oak species originating from the driest/warmest habitat (Q. pubescens compared to Q. robur and Q. petraea. Higher foliar osmolyte-N and potassium under drought and air warming were observed in all oak species when grown on calcareous versus acidic soil. These results indicate that species-specific differences in physiological mechanisms to compensate drought and elevated temperature are modified by soil acidity.

Dendrogeomorphology - a new tool to study drift-sand dynamics Netherlands Journal of Geosciences

NARCIS (Netherlands)

Ouden, den J.; Sass-Klaassen, U.; Copini, P.

2007-01-01

dendrogeomorphological approach is presented, using wood characteristics of native oak (Quercus robur L.) to infer dynamics of aeolian sediment transport in drift-sand areas. Wood samples, taken from oaks in two drift-sand areas, were analysed to study changes in tree-ring pattern and wood anatomy

Phenology, dichogamy, and floral synchronization in a northern red oak (Quercus rubra) seed orchard

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Lisa W. Alexander; Keith E. Woeste

2016-01-01

We developed a novel scoring system to assess spring phenology in a northern red oak (Quercus rubra L.) clonal seed orchard. The system was used to score from 304 to 364 ramets for three reproductive seasons and to place clones into early, intermediate, and late phenology classes. Although the absolute number of clones in each phenological class...

Analysis of Valonia Oak (Quercus aegylops Acorn Tannin and Wood Adhesives Application

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Soliman Abdalla

2015-09-01

Full Text Available The coupling of matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF mass spectrometry with 13C nuclear magnetic resonance (NMR is a suitable method for examining the composition of hydrolysable tannins and has been applied to the investigation of valonia oak (Quercus aegylops acorn tannin extract. Such methods can determine the extract’s structural aspects and other characteristics. It was determined that valonia oak acorn tannin extract is composed of mainly pentagalloylglucose structures; their rearrangement structures, vescalagin/castalagin (with linkages to flavogallonic acid and vescalin/castalin; ellagic acid and vescavaloneic/castavaloneic acid; and free gallic acid and glucose. Traces of catechin gallate were also observed in this tannin extract. The tannin from acorns of valonia oak was used to substitute up to 50% of the phenol used in the preparation of phenolic resins as adhesives for wood particleboard. These phenol-tannin-formaldehyde resins showed comparable performance to phenol-formaldehyde resins.

Accumulation of 137Cs and 90Sr in wood and bark of various types of oak and black alder plantings

International Nuclear Information System (INIS)

Perevolotskij, A.N.; Bulavik, I.M.; Perevolotskaya, T.V.; Paskrobko, L.A.; Andrush, S.N.

2008-01-01

Results of the evaluation of the influence of types of habitat edaphic conditions on 137Cs and 90Sr transition coefficients and their accumulation by wood and bark of English oak (Quercus robur L.) and black alder (Alnus glutinosa (L.) Gaertn) were presented. There was observed the particular influence of edaphic conditions on 137Cs and 90Sr accumulation by wood and bark of English oak. Lowering of 137Cs transition coefficients for the studied elements of phytomass was noted in the conditions of soil fertility increasing. Influence of soil moistening on 137Cs transition into wood and bark of oak trees was stated only in wood-sorrel and glague types of forests. Differences in accumulation of 90Sr by wood and bark of English oak in the studied range of edaphotopes were not proved. There was not found any differences in accumulation of both radionuclides by black alder trees in the typical for them edaphic conditions

Lake Washington Ship Canal, Seattle, Washington. Master Plan (DM 9)

Science.gov (United States)

1994-02-01

arizonica -- 306 ARCTOSTAPHYLLOS Ericaceae A16.1 Arctostaphyllos sp. Manzanita 120 A16.2 A. X Media "" 119... QUERCUS Fagacese Q1.1 Q. agrifolia Calif. Live Oak 24, 17 Ql.2 Q. canariensil "" 19 Q1.3 Q. ceris -- 18 Q1.4 Q. chrysolepLs Canyon Live Oak 210, 323, 1, 5...tremula ’Erecta’ Swedish Poplar Quercus robur ’Fastigiata’ Upright English Oak Stewartia pseudocamellia Japanese Stewartia Taxodium distichuni Bald Cypress £1 0 7- I- z -z 4~ 7< I -jII /2

Assemblages of saproxylic beetles on large downed trunks of oak.

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Milberg, Per; Bergman, Karl-Olof; Sancak, Kerem; Jansson, Nicklas

2016-03-01

Old living oaks (Quercus robur) are known as a very species-rich habitat for saproxylic beetles, but it is less clear to what extent such veteran trees differ from an even rarer feature: downed trunks of large oaks. In this study, we set out to sample this habitat, using window traps, with two aims: (1) to describe the variation of assemblages among downed trunks of different type and (2) to compare beetles on downed oaks with data from veteran standing trees. The results showed that trunk volume and sun exposure better explained assemblages as well as species numbers on downed trunks than did decay stage. Furthermore, species classified as facultative saproxylic species showed weak or no differentiation among downed trunks. Species with different feeding habits showed no apparent differentiation among downed trunks. Furthermore, species composition on dead, downed oak trunks differed sharply from that of living, veteran oaks. Wood or bark feeders were more common on veterans than downed trunks, but there was no difference for those species feeding on fungi or those feeding on insects and their remains. In conclusion, for a successful conservation of the saproxylic beetle fauna it is important to keep downed oak trunks, and particularly large ones, in forest and pastures as they constitute a saproxylic habitat that differs from that of living trees.

A fast and cost-effective approach to develop and map EST-SSR markers: oak as a case study

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Cherubini Marcello

2010-10-01

Full Text Available Abstract Background Expressed Sequence Tags (ESTs are a source of simple sequence repeats (SSRs that can be used to develop molecular markers for genetic studies. The availability of ESTs for Quercus robur and Quercus petraea provided a unique opportunity to develop microsatellite markers to accelerate research aimed at studying adaptation of these long-lived species to their environment. As a first step toward the construction of a SSR-based linkage map of oak for quantitative trait locus (QTL mapping, we describe the mining and survey of EST-SSRs as well as a fast and cost-effective approach (bin mapping to assign these markers to an approximate map position. We also compared the level of polymorphism between genomic and EST-derived SSRs and address the transferability of EST-SSRs in Castanea sativa (chestnut. Results A catalogue of 103,000 Sanger ESTs was assembled into 28,024 unigenes from which 18.6% presented one or more SSR motifs. More than 42% of these SSRs corresponded to trinucleotides. Primer pairs were designed for 748 putative unigenes. Overall 37.7% (283 were found to amplify a single polymorphic locus in a reference full-sib pedigree of Quercus robur. The usefulness of these loci for establishing a genetic map was assessed using a bin mapping approach. Bin maps were constructed for the male and female parental tree for which framework linkage maps based on AFLP markers were available. The bin set consisting of 14 highly informative offspring selected based on the number and position of crossover sites. The female and male maps comprised 44 and 37 bins, with an average bin length of 16.5 cM and 20.99 cM, respectively. A total of 256 EST-SSRs were assigned to bins and their map position was further validated by linkage mapping. EST-SSRs were found to be less polymorphic than genomic SSRs, but their transferability rate to chestnut, a phylogenetically related species to oak, was higher. Conclusion We have generated a bin map for oak

Patterns of contemporary hybridization inferred from paternity analysis in a four-oak-species forest

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Gailing Oliver

2009-12-01

Full Text Available Abstract Background Few studies address the issue of hybridization in a more than two-species context. The species-rich Quercus complex is one of the systems which can offer such an opportunity. To investigate the contemporary pattern of hybridization we sampled and genotyped 320 offspring from a natural mixed forest comprising four species of the European white oak complex: Quercus robur, Q. petraea, Q. pubescens, and Q. frainetto. Results A total of 165 offspring were assigned unambiguously to one of the pollen donors within the study plot. The minimum amount of effective pollen originating from outside the plot varied markedly among the seed parents, ranging from 0.18 to 0.87. The majority of the successful matings (64.1% occurred between conspecific individuals indicating the existence of reproductive barriers between oak species. However, the isolation was not complete since we found strong evidence for both first-generation (8.4% and later-generation hybrids (27.5%. Only two out of eight seed parents, belonging to Q. petraea and Q. robur, showed a high propensity to hybridize with Q. pubescens and Q. petraea, respectively. Significant structure of the effective pollen pools (Φpt = 0.069, P = 0.01 was detected in our sample. However, no support was found for the isolation by distance hypothesis. The proportion of hybrids was much higher (79% in the seed generation when compared to the adult tree generation. Conclusion First-generation hybrids were observed only between three out of six possible species combinations. Hybrids between one pair of species preferred to mate with one of their parental species. The observation of first and later-generation hybrids in higher frequency in acorns than in adults might be explained by selection against hybrid genotypes, the history of this uneven-aged forest or past introgression between species.

Species Diversity of Oak Stands and Its Significance for Drought Resistance

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Jan Kotlarz

2018-03-01

Full Text Available Drought periods have an adverse impact on the condition of oak stands. Research on different types of ecosystems has confirmed a correlation between plant species diversity and the adverse effects of droughts. The purpose of this study was to investigate the changes that occurred in an oak stand (Krotoszyn Plateau, Poland under the impact of the summer drought in 2015. We used a method based on remote sensing indices from satellite images in order to detect changes in the vegetation in 2014 and 2015. A positive difference was interpreted as an improvement, whereas a negative one was treated as a deterioration of the stand condition. The Shannon-Wiener species diversity was estimated using an iterative principal component analysis (PCA algorithm based on aerial images. We observed a relationship between the species indices of the individual forest divisions and their response to drought. The highest correlation between the index differences and the Shannon-Wiener indices was found for the Green Normalized Difference Vegetation Index (GNDVI index (+0.74. In addition, correlations were observed between the mean index difference and the percentage shares in the forest divisions of species such as Pinus sylvestris L. (P. sylvestris (+0.67 ± 0.08 and Quercus robur L. (Q. robur (−0.65 ± 0.10. Our results lead us to infer that forest management based on highly diverse habitats is more suitable to meet the challenges in the context of global climatic changes, characterized by increasingly frequent droughts.

The reconstruction of Lymantria dispar outbreaks by dendrochronological methods in the South Urals

Science.gov (United States)

Sergei Kucherov

1991-01-01

Interest in investigating the influence of extreme ecological factors on the radial growth of oak (Quercus robur L.) is bound up with oak dieback in the South Urals during the last decade. Factors contributing to this problem in the study area are hard winter frosts, late spring frosts, and Lymantria dispar L. outbreaks. To...

Drought-induced photosynthetic inhibition and autumn recovery in two Mediterranean oak species (Quercus ilex and Quercus suber).

Science.gov (United States)

Vaz, M; Pereira, J S; Gazarini, L C; David, T S; David, J S; Rodrigues, A; Maroco, J; Chaves, M M

2010-08-01

Responses of leaf water relations and photosynthesis to summer drought and autumn rewetting were studied in two evergreen Mediterranean oak species, Quercus ilex spp. rotundifolia and Quercus suber. The predawn leaf water potential (Ψ(lPD)), stomatal conductance (gs) and photosynthetic rate (A) at ambient conditions were measured seasonally over a 3-year period. We also measured the photosynthetic response to light and to intercellular CO₂ (A/PPFD and A/C(i) response curves) under water stress (summer) and after recovery due to autumn rainfall. Photosynthetic parameters, Vc(max), J(max) and triose phosphate utilization (TPU) rate, were estimated using the Farquhar model. RuBisCo activity, leaf chlorophyll, leaf nitrogen concentration and leaf carbohydrate concentration were also measured. All measurements were performed in the spring leaves of the current year. In both species, the predawn leaf water potential, stomatal conductance and photosynthetic rate peaked in spring, progressively declined throughout the summer and recovered upon autumn rainfall. During the drought period, Q. ilex maintained a higher predawn leaf water potential and stomatal conductance than Q. suber. During this period, we found that photosynthesis was not only limited by stomatal closure, but was also downregulated as a consequence of a decrease in the maximum carboxylation rate (Vc(max)) and the light-saturated rate of photosynthetic electron transport (J(max)) in both species. The Vc(max) and J(max) increased after the first autumnal rains and this increase was related to RuBisCo activity, leaf nitrogen concentration and chlorophyll concentration. In addition, an increase in the TPU rate and in soluble leaf sugar concentration was observed in this period. The results obtained indicate a high resilience of the photosynthetic apparatus to summer drought as well as good recovery in the following autumn rains of these evergreen oak species.

Bud burst and flowering phenology in a mixed oak forest from Eastern Romania

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Ecaterina Nicoleta Chesnoiu

2009-12-01

Full Text Available Bud burst and flowering phenology have been observed in year 2008 in a natural white oak species complex situated in eastern Romania. A total of 300 mature individuals was mapped and identified based on leaf morphology. The community consists of four oak species: Quercus pedunculiflora, Q. robur, Q. pubescens and Q. petraea. A set of 28 individuals could not be unambiguously classified to one or another species. Data on bud burst showed a normal distribution and the differences among species were small. The "very late" flushing was recorded on 15th of April, three weeks later when compared to early flushing individuals. The time period between the bud burst and the complete development of leaves was nearly the same in all oak species, varying on average, between 18.4 and 20.6 days. The spatial distribution of phenological groups within the complex appears to be non-randomly, because in many parts of the study plot exist groups in which most of the trees belong to the same phenological category. Our results indicate an overlap in flowering time for all oak species which occur in the area. The data support the hypothesis that interspecific gene flow is possible between closely related oak species.

Bud burst and flowering phenology in a mixed oak forest from Eastern Romania

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Ecaterina Nicoleta Chesnoiu

2009-11-01

Full Text Available Bud burst and flowering phenology have been observed in year 2008 ina natural white oak species complex situated in eastern Romania. A total of 300 mature individuals was mapped and identified based on leaf morphology. The community consists of four oak species: Quercus pedunculiflora, Q. robur, Q. pubescens and Q. petraea. A set of 28 individuals could not be unambiguously classified to one or another species. Data on bud burst showed a normal distribution and the differences among species were small. The "very late" flushing was recorded on 15th of April, three weeks later when compared to early flushing individuals. The time period between the bud burst and the complete development of leaves was nearly the same in all oak species, varying on average, between 18.4 and 20.6 days. The spatialdistribution of phenological groups within the complex appears to be non-randomly, because in many parts of the study plot exist groups in which most of the trees belong to the same phenological category. Our results indicate an overlap in flowering time for all oak species which occur in the area. The data support the hypothesis that interspecific gene flow is possible between closely related oak species.

First Approach to the Analytical Characterization of
Barrel-Aged Grape Marc Distillates Using Phenolic Compounds and Colour Parameters.

Science.gov (United States)

Rodríguez-Solana, Raquel; Salgado, José Manuel; Domínguez, José Manuel; Cortés-Diéguez, Sandra

2014-12-01

Phenolic compounds (benzoic and cinnamic acid derivatives) were determined by high-performance liquid chromatography with multiple wavelength detector (HPLC- -MWD) in grape marc distillates aged in Quercus petraea , Quercus robur and Quercus alba wooden barrels. In addition to colour indices and evaluable polyphenols, all samples were described by sensorial analysis. There were significant differences in the mean concentrations of the majority of phenolic compounds among the samples. Gallic and benzoic acids were the most abundant and samples aged in Q. robur from Galicia (NW of Spain) had the highest concentration of most of the determined phenols. Grape marc distillates aged in Q. robur obtained the highest values of all sensorial attributes, whereas samples aged in Q. petraea and Q. alba obtained similar scores. Principal component analysis accounted for 88.32% of total variance, showing a good separation of aged distillates in terms of phenolic compounds and colour characteristics, according to the species and origin of the oak wood used in the ageing process.

Effects of tornado damage, prescribed fire, and salvage logging on natural oak (Quercus spp.) regeneration in a xeric southern USA Coastal Plain oak/pine forest

Science.gov (United States)

Jeffery B. Cannon; J. Stephen Brewer

2013-01-01

Due in large part to fire exclusion, many oak-dominated (Quercus spp.) forests, woodlands, and savannas throughout eastern North America are being replaced by less diverse forest ecosystems. In the interior coastal plain of the southern United States, these forests are dominated in the mid- and understory by mesophytic species such as Acer...

Effect of Drying Method on the Permeability Coefficient of Oak Wood (Quercus infactoria

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Shuboo Salehpour

2014-05-01

Full Text Available In this study, the effect of drying method on the permeability coefficient of the oak wood (Quercus infectoria Oliv was studied. Freshly-cut logs of oak were prepared from Oureman, the east area of Kourdistan in Iran. Then, boards with nominal thickness of 6 cm were cut. The boards were dried using two methods. In the first method, the boards were air dried to the moisture content close to FSP for 45 days and then they were kiln dried using T5-D1 schedule. In the second method, the boards were dried from green condition to the final moisture content of 10% using T5-D1 schedule. Then, the permeability coefficient in the transverse and longitudinal directions in both heartwood and sapwood regions was measured, separately. Results showed that the permeability of oak boards dried by kiln drying method both in the transverse and longitudinal directions and also in the heartwood and sapwood regions was greater than that of those dried by the combined method (air drying + kiln drying.

Comparative gas-exchange in leaves of intact and clipped, natural and planted cherrybark oak (Quercus pagoda Raf.) seedlings

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Brian R. Lockhart; John D. Hodges

2005-01-01

Gas-exchange measurements, including C022-exchange rate (net photosynthesis), stomatal conductance, and transpiration, were conducted on intact and clipped cherrybark oak (Quercus pagoda Raf.) seedlings growing in the field and in a nursery bed. Seedlings in the field, released from midstory and understory woody competition,...

Conservation biogeography of red oaks (Quercus, section Lobatae) in Mexico and Central America.

Science.gov (United States)

Torres-Miranda, Andrés; Luna-Vega, Isolda; Oyama, Ken

2011-02-01

Oaks are dominant trees and key species in many temperate and subtropical forests in the world. In this study, we analyzed patterns of distribution of red oaks (Quercus, section Lobatae) occurring in Mexico and Central America to determine areas of species richness and endemism to propose areas of conservation. Patterns of richness and endemism of 75 red oak species were analyzed using three different units. Two complementarity algorithms based on species richness and three algorithms based on species rarity were used to identify important areas for conservation. A simulated annealing analysis was performed to evaluate and formulate effective new reserves for red oaks that are useful for conserving the ecosystems associated with them after the systematic conservation planning approach. Two main centers of species richness were detected. The northern Sierra Madre Oriental and Serranías Meridionales of Jalisco had the highest values of endemism. Fourteen areas were considered as priorities for conservation of red oak species based on the 26 priority political entities, 11 floristic units and the priority grid-cells obtained in the complementarity analysis. In the present network of Natural Protected Areas in Mexico and Central America, only 41.3% (31 species) of the red oak species are protected. The simulated annealing analysis indicated that to protect all 75 species of red oaks, 12 current natural protected areas need to be expanded by 120000 ha of additional land, and 26 new natural protected areas with 512500 ha need to be created. Red oaks are a useful model to identify areas for conservation based on species richness and endemism as a result of their wide geographic distribution and a high number of species. We evaluated and reformulated new reserves for red oaks that are also useful for the conservation of ecosystems associated with them.

Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula.

Science.gov (United States)

Pereira, Paulo; Ubeda, Xavier; Martin, Deborah; Mataix-Solera, Jorge; Guerrero, César

2011-02-01

Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO(2)) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40×70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (pfire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed fire will improve soil nutrient status without causing soil degradation and thus is considered to be a good management strategy. Copyright © 2010 Elsevier Inc. All rights reserved.

Характеристика водного обмена листьев Quercus robur L. и Quercus rubra L. в чистых и смешанных группах

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Анастасия КРИВОРУЧКО

2017-06-01

Full Text Available The peculiarities of water metabolism of the leaves of English oak (Quercus robur L. and red oak (Quercus rubra L. in pure and mixed groups were examined. Twelve-year-old forest plantations of both species on an area of 1.6 ha were the object of study. It was found that in both pure and mixed groups the leaves of Q. robur are characterized by more intense transpiration than Q. rubra. The joint growth of these species, on the whole, leads to a more active evaporation of water by Q. robur leaves than in the single-species groups. The leaves of Q. rubra in two-species groups lose less or the same amount of water in the transpiration process as in the single-species groups. The leaves of Q. rubra having a higher water storage capacity in both variants are characterized by a more uniform and stable daily course of transpiration. As a result of the joint growth, the water deficit in the leaves of Q. rubra increased in July and September compared to the pure groups. The differences in the leaves of Q. robur between the two studied sites are unreliable. The obtained data indicate the absence of an explicit negative mutual influence between the species on the water metabolism indices of their leaves. Реферат. Изучены особенности водного обмена листьев дуба обыкновенного (Quercus robur L. и дуба красного (Quercus rubra L. в чистых и смешанных группах. Объектами исследования были 12-летние лесные культуры обоих видов, площадью 1,6 га. Установлено, что как в чистых, так и в смешанных группах листья Q. robur характеризуются более интенсивной транспирацией в сравнении с Q. rubra. Совместный рост этих видов приводит, в целом, к более �

Recalcitrant Behavior of Cherrybark Oak Seed: An FT-IR Study of Desiccation Sensitivity in Quercus pagoda Raf. Acorns

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Sharon Sowa; Kristina F. Connor

2003-01-01

The recalcitrant behavior of cherrybark oak (Quercus pagoda Raf.) acorns was examined in terms of effects of moisture content on seed storage longevity and (short term) seed germination. Seed samples collected over two consecutive years were fully hydrated, then subjected to drying under ambient conditions of temperature and relative humidity on the...

First Approach to the Analytical Characterization of Barrel-Aged Grape Marc Distillates Using Phenolic Compounds and Colour Parameters

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Raquel Rodríguez-Solana

2014-01-01

Full Text Available Phenolic compounds (benzoic and cinnamic acid derivatives were determined by high-performance liquid chromatography with multiple wavelength detector (HPLC-MWD in grape marc distillates aged in Quercus petraea, Quercus robur and Quercus alba wooden barrels. In addition to colour indices and evaluable polyphenols, all samples were described by sensorial analysis. There were signifi cant diff erences in the mean concentrations of the majority of phenolic compounds among the samples. Gallic and benzoic acids were the most abundant and samples aged in Q. robur from Galicia (NW of Spain had the highest concentration of most of the determined phenols. Grape marc distillates aged in Q. robur obtained the highest values of all sensorial attributes, whereas samples aged in Q. petraea and Q. alba obtained similar scores. Principal component analysis accounted for 88.32 % of total variance, showing a good separation of aged distillates in terms of phenolic compounds and colour characteristics, according to the species and origin of the oak wood used in the ageing process.

Tree species richness, diversity, and regeneration status in different oak (Quercus spp. dominated forests of Garhwal Himalaya, India

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Sushma Singh

2016-09-01

Full Text Available Himalayan forests are dominated by different species of oaks (Quercus spp. at different altitudes. These oaks are intimately linked with hill agriculture as they protect soil fertility, watershed, and local biodiversity. They also play an important role in maintaining ecosystem stability. This work was carried out to study the diversity and regeneration status of some oak forests in Garhwal Himalaya, India. A total of 18 tree species belonging to 16 genera and 12 families were reported from the study area. Species richness varied for trees (4–7, saplings (3–10, and seedlings (2–6. Seedling and sapling densities (Ind/ha varied between 1,376 Ind/ha and 9,600 Ind/ha and 167 Ind/ha and 1,296 Ind/ha, respectively. Species diversity varied from 1.27 to 1.86 (trees, from 0.93 to 3.18 (saplings, and from 0.68 to 2.26 (seedlings. Total basal area (m2/ha of trees and saplings was 2.2–87.07 m2/ha and 0.20–2.24 m2/ha, respectively, whereas that of seedlings varied from 299 cm2/ha to 8,177 cm2/ha. Maximum tree species (20–80% had “good” regeneration. Quercus floribunda, the dominant tree species in the study area, showed “poor” regeneration, which is a matter of concern, and therefore, proper management and conservation strategies need to be developed for maintenance and sustainability of this oak species along with other tree species that show poor or no regeneration.

Sudden Oak Death - Eastern (Pest Alert)

Science.gov (United States)

Joseph O' Brien; Manfred Mielke; Steve Oak; Bruce Moltzan

2002-01-01

A phenomenon known as Sudden Oak Death was first reported in 1995 in central coastal California. Since then, tens of thousands of tanoaks (Lithocarpus densiflorus), coast live oaks (Quercus agrifolia), and California black oaks (Quercus kelloggii) have been killed by a newly identified fungus, Phytophthora ramorum. On these hosts, the fungus causes a bleeding canker on...

A role for atmospheric CO2 in preindustrial climate forcing

NARCIS (Netherlands)

Hoof, T.B. van; Wagner-Cremer, F.; Kürschner, W.M.; Visscher, H.

2008-01-01

Complementary to measurements in Antarctic ice cores, stomatal frequency analysis of leaves of land plants preserved in peat and lake deposits can provide a proxy record of preindustrial atmospheric CO2 concentration. CO2 trends based on leaf remains of Quercus robur (English oak) from the

Food, reproductive success and multiple breeding in the Great Tit Parus major

NARCIS (Netherlands)

Verboven, Nanette; Tinbergen, Joost M.; Verhulst, Simon

2001-01-01

We studied the reproductive success of facultatively double brooded Great Tits Parus major in relation to (seasonal) variation in abundance of their main food supply: caterpillars in Oak Quercus robur. Data were collected in two mixed woods (Vlieland and Hoge Veluwe, from 1985-1996). The caterpillar

Sudden oak death disease progression in oaks and tanoaks

Science.gov (United States)

Brice A. McPherson; Sylvia R. Mori; David L. Wood; Andrew J. Storer; Pavel Svihra; N. Maggi Kelly; Richard B. Standiford

2006-01-01

In March 2000, we established twenty disease progression plots in Marin County to monitor the progress of sudden oak death symptoms in coast live oak (Quercus agrifolia), California black oak (Q. kelloggii), and tanoak (Lithocarpus densiflorus) (McPherson and others 2005). Plots were located to encompass a...

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

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Scott R. Abella; Peter Z. Fulé

2008-01-01

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

Rooting stem cuttings of northern red oak (Quercus rubra L.) utilizing hedged stump sprouts formed on recently felled trees

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Matthew H. Gocke; Daniel J. Robinson

2010-01-01

The ability to root stem cuttings collected from hedged stump sprouts formed on recently felled trees was evaluated for 26 codominant northern red oak (Quercus rubra L.) trees growing in Durham County, NC. Sprouting occurred, the same year as felling, on 23 of the 26 tree stumps and sprout number was significantly and positively correlated with stump diameter. The...

Feedbacks between earlywood anatomy and non-structural carbohydrates affect spring phenology and wood production in ring-porous oaks

Science.gov (United States)

Pérez-de-Lis, Gonzalo; García-González, Ignacio; Rozas, Vicente; Olano, José Miguel

2016-10-01

Non-structural carbohydrates (NSC) play a central role in the construction and maintenance of a tree's vascular system, but feedbacks between the NSC status of trees and wood formation are not fully understood. We aimed to evaluate multiple dependencies among wood anatomy, winter NSC, and phenology for coexisting temperate (Quercus robur) and sub-Mediterranean (Q. pyrenaica) oaks along a water-availability gradient in the NW Iberian Peninsula. Sapwood NSC concentrations were quantified at three sites in December 2012 (N = 240). Leaf phenology and wood anatomy were surveyed in 2013. Structural equation modelling was used to analyse the interplay among hydraulic diameter (Dh), winter NSC, budburst date, and earlywood vessel production (EVP), while the effect of Dh and EVP on latewood width was assessed by using a mixed-effects model. NSC and wood production increased under drier conditions for both species. Q. robur showed a narrower Dh and lower soluble sugar (SS) concentration (3.88-5.08 % dry matter) than Q. pyrenaica (4.06-5.57 % dry matter), but Q. robur exhibited larger EVP and wider latewood (1403 µm) than Q. pyrenaica (667 µm). Stem diameter and Dh had a positive effect on SS concentrations, which were related to an earlier leaf flushing in both species. Sapwood sugar content appeared to limit EVP exclusively in Q. pyrenaica. In turn, Dh and EVP were found to be key predictors of latewood growth. Our results confirm that sapwood SS concentrations are involved in modulating growth resumption and xylem production in spring. Q. pyrenaica exhibited a tighter control of carbohydrate allocation to wood formation than Q. robur, which would play a role in protecting against environmental stress in the sub-Mediterranean area.

Fragmentation patterns of evergreen oak woodlands in Southwestern Iberia

DEFF Research Database (Denmark)

Costa, A.; Madeira, M.; Lima Santos, J.

2014-01-01

Mediterranean evergreen oak woodlands (composed of Quercus suber L. and Quercus rotundifolia Lam.) are becoming increasingly fragmented in the human-modified landscapes of Southwestern Portugal and Spain. Previous studies have largely neglected to assess the spatial changes of oak woodlands...... patterns of oak recruitment and therefore, its study may be helpful in highlighting future baselines for the sustainable management of oak woodlands....

Variation in flood tolerance of container-grown seedlings of swamp white oak, bur oak, and white oak

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Michael P. Walsh; J.W. Van Sambeek; Mark V. Coggeshall

2008-01-01

How much variation in flood tolerance exists among seedlings within oak species, given the flood frequency of sites from which acorns are collected, has been largely unexplored. Our studies examined initial growth and flood tolerance for seedlings of swamp white oak (Quercus bicolor Willd.), bur oak (Q. macrocarpa L.), and white...

Evaluation of spectral light management on growth of container-grown willow oak, nuttall oak and summer red maple

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Plant response to blue, red, gray or black shade cloth was evaluated with willow oak (Quercus phellos L.), Nuttall oak (Quercus nuttallii Palmer, Nuttall) and Summer Red maple (Acer rubrum L. ‘Summer Red’) liners. Light transmitted through the colored shade cloth had no influence on germination of ...

Properties of Hungarian oak(quercus conferta Kit. wood from the Hilandar Monastery forest

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Popović Zdravko

2007-01-01

Full Text Available This paper presents the study results of the basic physical and strength properties of Hungarian oak (Quercus conferta Kit. wood from the Kakovo Monastery forests of Hilandar Monastery in Greece. Wood properties were analyzed in detail, as an indispensable proof of wood quality and its use for joinery, interiors and wooden floors. The basic physical properties of wood (moisture content at the time of tree felling, density and volume porosity and the basic strength properties (compressive strength, bending strength and module of elasticity were researched. The results are presented in Tables and in Diagrams with statistical parameters and compared to the literature data. The correlation of the study properties of wood was also analyzed.

Seasonal abundance and biology of sporophagous thrips and notes on other thrips (Insecta, Thysanoptera) on the Mediterranean oak, Quercus rotundifolia L. in Navarra (N Spain)

OpenAIRE

Goldarazena, A.; Mound, L. A.

1999-01-01

This paperrecords the seasonal abundance of four species of sporophagous thrips collected on the Mediterranean oak, Quercus rotundifolia L., in the Mediterranean area of Navarra (N Spain). The life cycles of Cornpsothrips albosignatus (Reuter), Priesneriella clavicornis (Knechtel); Megalothrips bonannii Uzel and Cryptohrips nigripes (Reuter) are reported, and notes given about habitat specificity and wing development. Notes about host specific Terebrantia thrips of the Mediterranean oak are a...

Assessing Methods to Protect Susceptible Oak and Tanoak Stands from Sudden Oak Death

Science.gov (United States)

Tedmund Swiecki; Elizabeth Bernhardt

2010-01-01

Landowners and managers have been seeking ways to protect susceptible oak (Quercus) species and tanoak (Lithocarpus densiflorus) from sudden oak death (SOD) caused by Phytophthora ramorum. Because disease epidemiology differs between tanoaks and susceptible oaks, we are testing different control strategies...

Foliage response of young central European oaks to air warming, drought and soil type.

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Günthardt-Goerg, M S; Kuster, T M; Arend, M; Vollenweider, P

2013-01-01

Three Central European oak species, with four provenances each, were experimentally tested in 16 large model ecosystem chambers for their response to passive air warming (AW, ambient +1-2 °C), drought (D, -43 to -60% irrigation) and their combination (AWD) for 3 years on two forest soil types of pH 4 or 7. Throughout the entire experiment, the influence of the different ambient and experimental climates on the oak trees was strong. The morphological traits of the Quercus species were affected in opposing ways in AW and D treatments, with a neutral effect in the AWD treatment. Biochemical parameters and LMA showed low relative plasticity compared to the morphological and growth parameters. The high plasticity in physiologically important parameters of the three species, such as number of intercalary veins or leaf size, indicated good drought acclimation properties. The soil type influenced leaf chlorophyll concentration, C/N and area more than drought, whereas foliage mass was more dependent on drought than on soil type. Through comparison of visible symptom development with the water deficits, a drought tolerance threshold of -1.3 MPa was determined. Although Q. pubescens had xeromorphic leaf characteristics (small leaf size, lower leaf water content, high LMA, pilosity, more chlorophyll, higher C/N) and less response to the treatments than Q. petraea and Q. robur, it suffered more leaf drought injury and shedding of leaves than Q. petraea. However, if foliage mass were used as the criterion for sustainable performance under a future climate, Q. robur would be the most appropriate species. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

GLELE KAKAI R.G. et al;.mdi

African Journals Online (AJOL)

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Pterocarpus erinaceus is an arborescent deciduous legume tree of African savannas and dry forests growing in natural stands in the sudanian zone in Benin. ... soudano-guinéenne définie par White (1983) comme celle des forêts claires à ..... Compatible stem taper and stem volume functions for oak (Quercus robur L and.

Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula

Science.gov (United States)

Pereira, P.; beda, X.; Martin, D.; Mataix-Solera, J.; Guerrero, C.

2011-01-01

Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO2) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40??70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (p<0.001), water-soluble Ca, Mg, Na, SiO2 and TS and a decrease in water-soluble Mn, Fe and Zn. Differences were identified between oak species for water-soluble K, Al and Fe. In Q.S samples we registered a significant increase in the first two elements p<0.001 and p<0.01, respectively, and a non-significant impact in the third, at p<0.05. In Q.R data we identified a non-significant impact on water-soluble K and Al and a significant decrease in water-soluble Fe (p<0.05). These differences are probably due to vegetation characteristics and burn severity. The fire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed

Sorption of lipophilic organic compunds to wood and implications for their environmental fate

DEFF Research Database (Denmark)

Trapp, Stefan; Miglioranza, S.B.; Mosbæk, Hans

2001-01-01

The sorption from water to wood (KWood) of 10 organic chemicals (logKOW, 1.48-6.20) was experimentally determined for oak (Quercus robur) and basket willow (Salix viminalis). Linear regression yielded log KWood ) -0.27 (( 0.25) + 0.632 (( 0.063)log KOW for oak (r ) 0.90, n ) 27) and log KWood ) -...... time. If metabolism inside the stem occurs, wood can serve as a “safe sink” for environmental chemicals. This might be of use in phytoremediation....

Genetic structure of a natural oak community in central Italy: Evidence of gene flow between three sympatric white oak species (Quercus, Fagaceae

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Gaby Antonecchia

2015-12-01

Full Text Available Incomplete reproductive barriers between species, especially in sympatric areas where several species coexist, may result in hybridization and an increase in genetic diversity. Here we assessed the amount of genetic diversity in a community of three interfertile and sympatric European oaks (Quercus frainetto Ten., Q. petraea Liebl. Matt. and Q. pubescens Willd. situated in central Italy. We used 11 microsatellite markers derived from Expressed Sequence Tag (EST-SSRs and we implemented a Bayesian clustering analysis to assign individuals to species or hybrids. All genotyped loci were polymorphic for all the species and three genetic clusters corresponding to each species were detected. Significant differences and a higher level of gene flow were observed between the three oak species. Occurrence of hybrids varied markedly within the studied area: hybrids between Q. petraea and Q, pubescens were the most frequent, while hybrids between Q. petraea and Q. frainetto were particularly rare. Q. pubescens and Q. petraea showed the highest number of alleles compared to Q. frainetto,which was characterized by a low number of private, but highly frequent, alleles. However, Q. frainetto showed a lower genetic diversity and a stronger reproductive isolation from the other two oak species.

Imeretian oak and a great capricorn beetle – the problem of relations on the territory of Ajameti Managed Reserve (Republic of Georgia

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Matsiakh Iryna

2017-09-01

Full Text Available The old-growth endemic Imeretian oak [Quercus robur subsp. imeretina (Steven ex Woronow Menitsky, 1968] is a protected relict Tertiary period tree still preserved in Ajameti Managed Reserve (Republic of Georgia. For a long time, these forests were experienced to the strong anthropogenic influence. The old-age oak trees and the development of root and stem rot have promoted the settlement of great capricorn beetle [Cerambyx cerdo Linnaeus, 1758 (Coleoptera: Cerambycidae]. Both of species are protected under the EU Habitats Directive and listed in the IUCN Red List of Threatened Species. The investigation of settling degree of C. cerdo was conducted at two areas, Ajameti and Vartsikhe, on the edge and in the middle of oak forests in June and October 2014. On both the areas, the number of trees with fly exit holes of great capricorn beetle was higher on the margin of forests where plantations suffer greater of human impact. The number of fly exit holes of imago is significantly increased due to deterioration of sanitary condition of forests. The measures of management conservation at Ajameti Managed Reserve were proposed.

Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States

Science.gov (United States)

Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G.

2014-07-01

Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6 %-248 %. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

The diversity of (13)C isotope discrimination in a Quercus robur full-sib family is associated with differences in intrinsic water use efficiency, transpiration efficiency, and stomatal conductance.

Science.gov (United States)

Roussel, Magali; Dreyer, Erwin; Montpied, Pierre; Le-Provost, Grégoire; Guehl, Jean-Marc; Brendel, Oliver

2009-01-01

(13)C discrimination in organic matter with respect to atmospheric CO(2) (Delta(13)C) is under tight genetic control in many plant species, including the pedunculate oak (Quercus robur L.) full-sib progeny used in this study. Delta(13)C is expected to reflect intrinsic water use efficiency, but this assumption requires confirmation due to potential interferences with mesophyll conductance to CO(2), or post-photosynthetic discrimination. In order to dissect the observed Delta(13)C variability in this progeny, six genotypes that have previously been found to display extreme phenotypic values of Delta(13)C [either very high ('high Delta') or low ('low Delta') phenotype] were selected, and transpiration efficiency (TE; accumulated biomass/transpired water), net CO(2) assimilation rate (A), stomatal conductance for water vapour (g(s)), and intrinsic water use efficiency (W(i)=A/g(s)) were compared with Delta(13)C in bulk leaf matter, wood, and cellulose in wood. As expected, 'high Delta' displayed higher values of Delta(13)C not only in bulk leaf matter, but also in wood and cellulose. This confirmed the stability of the genotypic differences in Delta(13)C recorded earlier. 'High Delta' also displayed lower TE, lower W(i), and higher g(s). A small difference was detected in photosynthetic capacity but none in mesophyll conductance to CO(2). 'High Delta' and 'low Delta' displayed very similar leaf anatomy, except for higher stomatal density in 'high Delta'. Finally, diurnal courses of leaf gas exchange revealed a higher g(s) in 'high Delta' in the morning than in the afternoon when the difference decreased. The gene ERECTA, involved in the control of water use efficiency, leaf differentiation, and stomatal density, displayed higher expression levels in 'low Delta'. In this progeny, the variability of Delta(13)C correlated closely with that of W(i) and TE. Genetic differences of Delta(13)C and W(i) can be ascribed to differences in stomatal conductance and stomatal

Physiological Responses to Prolonged Drought Differ Among Three Oak (Quercus) Species

Science.gov (United States)

Cooper, C. E.; Moore, G. W.; Vogel, J. G.; Muir, J. P.

2015-12-01

The physiological response of plants to water stress provides insights into which species may survive in exceptional drought conditions. This study conducted on a remnant post oak savanna site in College Station, Texas, examined how drought affected the physiology of three native oak species. In June 2014, after a period of equal watering, we subjected three year old Quercus shumardii (Shumard oak; SO), Q. virginiana (live oak; LO), and Q. macrocarpa (bur oak; BO) saplings to one of two watering treatments: 1) watered, receiving the equivalent of theaverage precipitation rate and 2) droughted, receiving a 100% reduction in precipitation. We measured predawn (ΨPD) and midday (ΨMD) leaf water potential; midday gas exchange (MGE) parameters including photosynthesis (Al), transpiration (T), stomatal conductance (gsw); and leaf soluble (SS) and non-soluble sugar (NSS) concentrations monthly between June and October 2014. Drought stress responses were evident after only one month of induced drought. Droughted saplings showed reduced ΨPD, ΨMD, and MGE (P ≤ 0.05) in comparison to watered saplings of the same species. LO saplings exhibited greater MGE (P ≤ 0.05) while maintaining similar LWP to their respective watered and droughted BO and SO counterparts. Droughted LO exhibited MGE rates similar to those of watered BO and SO (P ≤ 0.05), while watered LO adjusted its MGE rates to changes in water availability better than BO and LO during short-term drought. Compared to water saplings, droughted saplings had greater leaf SS (P = 0.08) and lower NSS concentrations (P = 0.10), possibly due to the conversion of NSS to SS and other simple compounds and reduced consumption of SS for growth by the droughted saplings. Although SO and BO exhibited similar photosynthesis rates, leaf total sugar (SS+NSS) concentration was greater in SO (P ≤ 0.05). By displaying the greatest average photosynthesis rate (P ≤ 0.05), LO should have accumulated the greatest amount of carbon

A phenological timetable of oak growth under experimental drought and air warming.

Directory of Open Access Journals (Sweden)

Thomas M Kuster

Full Text Available Climate change is expected to increase temperature and decrease summer precipitation in Central Europe. Little is known about how warming and drought will affect phenological patterns of oaks, which are considered to possess excellent adaptability to these climatic changes. Here, we investigated bud burst and intra-annual shoot growth of Quercus robur, Q. petraea and Q. pubescens grown on two different forest soils and exposed to air warming and drought. Phenological development was assessed over the course of three growing seasons. Warming advanced bud burst by 1-3 days °C⁻¹ and led to an earlier start of intra-annual shoot growth. Despite this phenological shift, total time span of annual growth and shoot biomass were not affected. Drought changed the frequency and intensity of intra-annual shoot growth and advanced bud burst in the subsequent spring of a severe summer drought by 1-2 days. After re-wetting, shoot growth recovered within a few days, demonstrating the superior drought tolerance of this tree genus. Our findings show that phenological patterns of oaks are modified by warming and drought but also suggest that ontogenetic factors and/or limitations of water and nutrients counteract warming effects on the biomass and the entire span of annual shoot growth.

Holm Oak (Quercus ilex L.) canopy as interceptor of airborne trace elements and their accumulation in the litter and topsoil

International Nuclear Information System (INIS)

Fantozzi, Federica; Monaci, Fabrizio; Blanusa, Tijana; Bargagli, Roberto

2013-01-01

We investigated the role of urban Holm Oak (Quercus ilex L.) trees as an airborne metal accumulators and metals' environmental fate. Analyses confirmed Pb, Cd, Cu and Zn as a main contaminants in Siena's urban environment; only Pb concentrations decreased significantly compared to earlier surveys. Additionally, we determined chemical composition of tree leaves, litter and topsoil (underneath/outside tree crown) in urban and extra-urban oak stands. Most notably, litter in urban samples collected outside the canopy had significantly lower concentrations of organic matter and higher concentrations of Pb, Cu, Cd and Zn than litter collected underneath the canopy. There was a greater metals' accumulation in topsoil, in samples collected under the tree canopy and especially near the trunk (‘stemflow area’). Thus, in urban ecosystems the Holm Oak stands likely increase the soil capability to bind metals. -- Highlights: ► Of the main metal contaminants only leaf Pb concentrations decreased in the period 1994–2011. ► Leaf Cd, Cr, Cu, Pb and Zn concentrations were higher in urban than in extra urban park. ► In urban park litter, Cu, Cd, Pb and Zn concentrations were higher outside than underneath the tree crown. ► Conversely, in urban park soil, Cu, Cd, Pb and Zn concentrations were lower outside the crown. ► Soil therefore behaves as a sink for metal contaminants such as Cu, Pb and Cd. -- Quercus ilex leaves are efficient interceptors of airborne trace elements in urban environments and we found an increased accumulation of metals in topsoil under the tree canopy

Risk analysis and guidelines for harvest activities in wisconsin oak timberlands to minimize oak wilt threat

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Jennifer Juzwik; Jane Cummings-Carlson; Kyoko Scanlon

2010-01-01

Oaks (Quercus spp.) are an important species group in the forests of Wisconsin. The State’s timberland typed as oak-hickory forest was estimated at 2.9 million acres in 1996. Growing stock volume for red oak was estimated at 2.4 billion cubic feet, whereas select white oak volume was estimated to be 927 million cubic feet. Oak wilt, the oak disease...

Drivers of radial growth and carbon isotope discrimination of bur oak (Quercus macrocarpa Michx.) across continental gradients in precipitation, vapour pressure deficit and irradiance

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Steven L. Voelker; Frederick C. Meinzer; Barbara Lachenbruch; J. Renee Brooks; Richard P. Guyette

2014-01-01

Tree-ring characteristics are commonly used to reconstruct climate variables, but divergence from the assumption of a single biophysical control may reduce the accuracy of these reconstructions. Here, we present data from bur oaks (Quercus macrocarpa Michx.) sampled within and beyond the current species bioclimatic envelope to identify the primary...

Soil properties and understory herbaceous biomass in forests of three species of Quercus in Northeast Portugal

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Marina Castro

2014-12-01

Full Text Available Aim of study: This paper aims to characterize some soil properties within the first 25 cm of the soil profile and the herbaceous biomass in Quercus forests, and the possible relationships between soil properties and understory standing biomass.Area of study: Three monoespecific Quercus forests (Q. suber L., Q. ilex subsp. rotundifolia Lam. and Q. pyrenaica Willd in NE Portugal.Material and methods: During 1999 and 2000 soil properties (pH-KCl, total soil nitrogen (N, soil organic carbon (SOC, C/N ratio, available phosphorus (P, and available potassium (K and herbaceous biomass production of three forest types: Quercus suber L., Quercus ilex subsp. rotundifolia Lam. and Quercus pyrenaica Willd were studied.Main results: The results showed a different pattern of soil fertility (N, SOC, P, K in Quercus forests in NE of Portugal. The C/N ratio and the herbaceous biomass confirmed this pattern. Research highlights: There is a pattern of Quercus sp. distribution that correlates with different soil characteristics by soil characteristics in NE Portugal. Q. pyrenaica ecosystems were found in more favoured areas (mesic conditions; Q. rotundifolia developed in nutrient-poor soils (oligotrophic conditions; and Q. suber were found in intermediate zones.Keywords: fertility; biomass; C/N ratio; cork oak; holm oak; pyrenean oak.

A comprehensive assessment of the transcriptome of cork oak (Quercus suber) through EST sequencing.

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Pereira-Leal, José B; Abreu, Isabel A; Alabaça, Cláudia S; Almeida, Maria Helena; Almeida, Paulo; Almeida, Tânia; Amorim, Maria Isabel; Araújo, Susana; Azevedo, Herlânder; Badia, Aleix; Batista, Dora; Bohn, Andreas; Capote, Tiago; Carrasquinho, Isabel; Chaves, Inês; Coelho, Ana Cristina; Costa, Maria Manuela Ribeiro; Costa, Rita; Cravador, Alfredo; Egas, Conceição; Faro, Carlos; Fortes, Ana M; Fortunato, Ana S; Gaspar, Maria João; Gonçalves, Sónia; Graça, José; Horta, Marília; Inácio, Vera; Leitão, José M; Lino-Neto, Teresa; Marum, Liliana; Matos, José; Mendonça, Diogo; Miguel, Andreia; Miguel, Célia M; Morais-Cecílio, Leonor; Neves, Isabel; Nóbrega, Filomena; Oliveira, Maria Margarida; Oliveira, Rute; Pais, Maria Salomé; Paiva, Jorge A; Paulo, Octávio S; Pinheiro, Miguel; Raimundo, João A P; Ramalho, José C; Ribeiro, Ana I; Ribeiro, Teresa; Rocheta, Margarida; Rodrigues, Ana Isabel; Rodrigues, José C; Saibo, Nelson J M; Santo, Tatiana E; Santos, Ana Margarida; Sá-Pereira, Paula; Sebastiana, Mónica; Simões, Fernanda; Sobral, Rómulo S; Tavares, Rui; Teixeira, Rita; Varela, Carolina; Veloso, Maria Manuela; Ricardo, Cândido P P

2014-05-15

Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management. We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of ~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at http://www.corkoakdb.org. This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.

Flood-Ring Formation and Root Development in Response to Experimental Flooding of Young Quercus robur Trees

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Copini, Paul; den Ouden, Jan; Robert, Elisabeth M. R.; Tardif, Jacques C.; Loesberg, Walter A.; Goudzwaard, Leo; Sass-Klaassen, Ute

2016-01-01

Spring flooding in riparian forests can cause significant reductions in earlywood-vessel size in submerged stem parts of ring-porous tree species, leading to the presence of ‘flood rings’ that can be used as a proxy to reconstruct past flooding events, potentially over millennia. The mechanism of flood-ring formation and the relation with timing and duration of flooding are still to be elucidated. In this study, we experimentally flooded 4-year-old Quercus robur trees at three spring phenophases (late bud dormancy, budswell, and internode expansion) and over different flooding durations (2, 4, and 6 weeks) to a stem height of 50 cm. The effect of flooding on root and vessel development was assessed immediately after the flooding treatment and at the end of the growing season. Ring width and earlywood-vessel size and density were measured at 25- and 75-cm stem height and collapsed vessels were recorded. Stem flooding inhibited earlywood-vessel development in flooded stem parts. In addition, flooding upon budswell and internode expansion led to collapsed earlywood vessels below the water level. At the end of the growing season, mean earlywood-vessel size in the flooded stem parts (upon budswell and internode expansion) was always reduced by approximately 50% compared to non-flooded stem parts and 55% compared to control trees. This reduction was already present 2 weeks after flooding and occurred independent of flooding duration. Stem and root flooding were associated with significant root dieback after 4 and 6 weeks and mean radial growth was always reduced with increasing flooding duration. By comparing stem and root flooding, we conclude that flood rings only occur after stem flooding. As earlywood-vessel development was hampered during flooding, a considerable number of narrow earlywood vessels present later in the season, must have been formed after the actual flooding events. Our study indicates that root dieback, together with strongly reduced hydraulic

Using common mycorrhizal networks for controlled inoculation of Quercus spp. with Tuber melanosporum: the nurse plant method.

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Pereira, Guillermo; Palfner, Götz; Chávez, Daniel; Suz, Laura M; Machuca, Angela; Honrubia, Mario

2013-07-01

The high cost and restricted availability of black truffle spore inoculum for controlled mycorrhiza formation of host trees produced for truffle orchards worldwide encourage the search for more efficient and sustainable inoculation methods that can be applied globally. In this study, we evaluated the potential of the nurse plant method for the controlled inoculation of Quercus cerris and Quercus robur with Tuber melanosporum by mycorrhizal networks in pot cultures. Pine bark compost, adjusted to pH 7.8 by liming, was used as substrate for all assays. Initially, Q. robur seedlings were inoculated with truffle spores and cultured for 12 months. After this period, the plants presenting 74 % mycorrhizal fine roots were transferred to larger containers. Nurse plants were used for two treatments of two different nursling species: five sterilized acorns or five 45-day-old, axenically grown Q. robur or Q. cerris seedlings, planted in containers around the nurse plant. After 6 months, colonized nursling plant root tips showed that mycorrhiza formation by T. melanosporum was higher than 45 % in the seedlings tested, with the most successful nursling combination being Q. cerris seedlings, reaching 81 % colonization. Bulk identification of T. melanosporum mycorrhizae was based on morphological and anatomical features and confirmed by sequencing of the internal transcribed spacer region of the ribosomal DNA of selected root tips. Our results show that the nurse plant method yields attractive rates of mycorrhiza formation by the Périgord black truffle and suggest that establishing and maintaining common mycorrhizal networks in pot cultures enables sustained use of the initial spore inoculum.

Ecological characteristics of a Hungarian summer truffle (Tuber aestivum Vittad. producing area

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Csorbai A. Gógán

2013-12-01

Full Text Available Hungary has outstanding environment for natural truffle production in some regions including plain and hilly areas. The most famous of all the natural summer truffle (Tuber aestivum Vittad. habitats is the commonly called Jászság region. This area is situated in the middle of Hungary, between river Danube and Tisza. The flatland area is basically covered by river alluviums with main soils of chernozems, fluvisols, solonchaks and arenosols. Climate of the region is typically continental: warm and dry summers and cold winters vary. The area is traditionally of agricultural use, although strong afforestation was made in the late 1950’s. The English oak (Quercus robur L. populations planted at that time gave a basis for current excellent truffle production. Nowadays the region has proved to be the best natural summer truffle (T. aestivum producing area of Hungary with early season opening (June and high quality truffles as early as August. In the research the best truffle producing forest blocks were selected for ecological investigation. Results of the detailed site description showed uniform climate characteristics and dominance of English oak (Q. robur or mixed English oak-Turkey oak (Quercus cerris L. forests. Soil types revealed differences from earlier findings: dominance of gleysols and water affected chernozems was declared. Soil chemical parameters are in accordance with literature data: pH, organic matter and active carbonate content of the examined soils fall within the range indicated as the requirement of T. aestivum.

Removal of acorns of the alien oak Quercus rubra on the ground by scatter-hoarding animals in Belgian forests

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Merceron, NR.

2017-01-01

Full Text Available Description of the subject. Quercus rubra L. is considered an invasive species in several European countries. However, little is known about its dispersal in the introduced range. Objectives. We investigated the significance of animal dispersal of Q. rubra acorns on the ground by vertebrates in its introduced range, and identified the animal species involved. Method. During two consecutive autumns, the removal of acorns from Q. rubra and from a native oak was assessed weekly in forest sites in Belgium. We used automated detection camera traps to identify the animals that removed acorns. Results. Quercus rubra acorns were removed by wood mice (Apodemus sylvaticus L., red squirrels (Sciurus vulgaris L., rats (Rattus sp., and wild boars (Sus scrofa L.. The two former are scatter-hoarding rodents and can be considered potential dispersers. Conclusions. Dispersal of Q. rubra acorns in Western Europe by scatter-hoarding animals may help the species increasingly colonize forest ecosystems.

Elevated UV-B radiation incident on Quercus robur leaf canopies enhances decomposition of resulting leaf litter in soil

International Nuclear Information System (INIS)

Newsham, K.K.; Greenslade, P.D.; Kennedy, V.H.; McLeod, A.R.

1999-01-01

We examined whether the exposure of Quercus robur L. to elevated UV-B radiation (280–315 nm) during growth would influence leaf decomposition rate through effects on litter quality. Saplings were exposed for eight months at an outdoor facility in the UK to a 30% elevation above the ambient level of erythemally weighted UV-B radiation under UV-B treatment arrays of fluorescent lamps filtered with cellulose diacetate, which transmitted both UV-B and UV-A (315–400 nm) radiation. Saplings were exposed to elevated UV-A alone under control arrays of lamps filtered with polyester and to ambient radiation under unenergised arrays of lamps. Abscised leaves from saplings were enclosed in 1 mm2 mesh nylon bags, placed in a Quercus–Fraxinus woodland and were sampled at 0.11, 0.53, 1.10 and 1.33 years for dry weight loss, chemical composition and saprotrophic fungal colonization. At abscission, litters from UV-A control arrays had ≈ 7.5% higher lignin/nitrogen ratios than those from UV-B treatment and ambient arrays (P < 0.06). Dry weight loss of leaves treated with elevated UV-B radiation during growth was 2.5% and 5% greater than that of leaves from UV-A control arrays at 0.53 and 1.33 years, respectively. Litter samples from UV-B treatment arrays lost more nitrogen and phosphorus than samples from ambient arrays and more carbon than samples from UV-A control arrays. The annual fractional weight loss of litter from UV-B treatment arrays was 8% and 6% greater than that of litter from UV-A control and ambient arrays, respectively. Regression analyses indicated that the increased decomposition rate of UV-B treated litters was associated with enhanced colonization of leaves by basidiomycete fungi, the most active members of the soil fungal community, and that the frequency of these fungi was negatively associated with the initial lignin/nitrogen ratio of leaves. (author)

Do chestnut, northern red, and white oak germinant seedlings respond similary to light treatments? II. Gas exchange and chlorophyll responses

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Joanne Rebbeck; Amy Scherzer; Kurt. Gottschalk

2012-01-01

Understanding differences in physiological and growth strategies in low-light environments among upland oak species may help managers address the challenges of oaks' poor regeneration. Gas exchange and chlorophyll content were measured for northern red oak (Quercus rubra L.), chestnut oak (Quercus prinus L.), and white oak (...

Climatic origins predict variation in photoprotective leaf pigments in response to drought and low temperatures in live oaks (Quercus series Virentes).

Science.gov (United States)

Ramírez-Valiente, Jose A; Koehler, Kari; Cavender-Bares, Jeannine

2015-05-01

Climate is a major selective force in nature. Exploring patterns of inter- and intraspecific genetic variation in functional traits may explain how species have evolved and may continue evolving under future climate change. Photoprotective pigments play an important role in short-term responses to climate stress in plants but knowledge of their long-term role in adaptive processes is lacking. In this study, our goal was to determine how photoprotective mechanisms, morphological traits and their plasticity have evolved in live oaks (Quercus series Virentes) in response to different climatic conditions. For this purpose, seedlings originating from 11 populations from four live oak species (Quercus virginiana, Q. geminata, Q. fusiformis and Q. oleoides) were grown under contrasting common environmental conditions of temperature (tropical vs temperate) and water availability (droughted vs well-watered). Xanthophyll cycle pigments, anthocyanin accumulation, chlorophyll fluorescence parameters and leaf anatomical traits were measured. Seedlings originating from more mesic source populations of Q. oleoides and Q. fusiformis increased the xanthophyll de-epoxidation state under water-limiting conditions and showed higher phenotypic plasticity for this trait, suggesting adaptation to local climate. Likewise, seedlings originating from warmer climates had higher anthocyanin concentration in leaves under cold winter conditions but not higher de-epoxidation state. Overall, our findings suggest that (i) climate has been a key factor in shaping species and population differences in stress tolerance for live oaks, (ii) anthocyanins are used under cold stress in species with limited freezing tolerance and (iii) xanthophyll cycle pigments are used when photoprotection under drought conditions is needed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Photosynthetic efficiency of Pedunculate oak seedlings under simulated water stress

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Popović Zorica

2010-01-01

Full Text Available Photosynthetic performance of seedlings of Quercus robur exposed to short-term water stress in the laboratory conditions was assessed through the method of induced fluorometry. The substrate for seedlings was clayey loam, with the dominant texture fraction made of silt, followed by clay and fine sand, with total porosity 68.2%. Seedlings were separated in two groups: control (C (soil water regime in pots was maintained at the level of field water capacity and treated (water-stressed, WS (soil water regime was maintained in the range of wilting point and lentocapillary capacity. The photosynthetic efficiency was 0.642±0.25 and 0.522±0.024 (WS and C, respectively, which was mostly due to transplantation disturbances and sporadic leaf chlorosis. During the experiment Fv/Fm decreased in both groups (0.551±0.0100 and 0.427±0.018 in C and WS, respectively. Our results showed significant differences between stressed and control group, in regard to both observed parameters (Fv/Fm and T½. Photosynthetic efficiency of pedunculate oak seedlings was significantly affected by short-term water stress, but to a lesser extent than by sufficient watering.

Phylogeographical variation of chloroplast DNA in holm oak (Quercus ilex L.).

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Lumaret, R; Mir, C; Michaud, H; Raynal, V

2002-11-01

Variation in the lengths of restriction fragments (RFLPs) of the whole chloroplast DNA molecule was studied in 174 populations of Quercus ilex L. sampled over the entire distribution of this evergreen and mainly Mediterranean oak species. By using five endonucleases, 323 distinct fragments were obtained. From the 29 and 17 cpDNA changes identified as site and length mutations, respectively, 25 distinct chlorotypes were distinguished, mapped and treated cladistically with a parsimony analysis, using as an outgroup Q. alnifolia Poech, a closely related evergreen oak species endemic to Cyprus where Q. ilex does not grow. The predominant role of Q. ilex as maternal parent in hybridization with other species was reflected by the occurrence of a single very specific lineage of related chlorotypes, the most ancestral and recent ones being located in the southeastern and in the northwestern parts of the species' geographical distribution, respectively. The lineage was constituted of two clusters of chlorotypes observed in the 'ilex' morphotyped populations of the Balkan and Italian Peninsulas (including the contiguous French Riviera), respectively. A third cluster was divided into two subclusters identified in the 'rotundifolia' morphotyped populations of North Africa, and of Iberia and the adjacent French regions, respectively. Postglacial colonization probably started from three distinct southerly refugia located in each of the three European peninsulas, and a contact area between the Italian and the Iberian migration routes was identified in the Rhône valley (France). Chlorotypes identical or related to those of the Iberian cluster were identified in the populations from Catalonia and the French Languedoc region, which showed intermediate morphotypes, and in the French Atlantic populations which possessed the 'ilex' morphotype, suggesting the occurrence of adaptive morphological changes in the northern part of the species' distribution.

Use of forest species associated to oak forests (Quercus humboldtii Bonpl.) for energetic purposes, in three villages of the Encino municipality in Santander

International Nuclear Information System (INIS)

Diaz Silva, Monica Rocio de las Mercedes

2010-01-01

We surveyed the firewood consumption for energetic purposes from the oak forest of the Patios Altos and Canada villages in Encino-Santander. Tools used to collect data were: structured surveys, open interviews and participant observation to those families dependent upon forest resources. Twenty-one species for domestic use were recorded, from which seven were related to the oak for est. The most preferred and used tree species was the Oak (Quercus humboldtii Bonpl) followed by the Laurel (Morella pubescens (Humb. and Bonpl. ex Willd.) Wilbur). Results show that 98% of the population uses only firewood and firewood alternated with gas, which suggests the importance of firewood to the community. Firewood consumption per person is 3.6 + - 1.35 kg per day, while annual consumption of the whole group (54 families) is the 354.78 kg per year. This usage corresponds to native tree species (78.2%), native shrubs 12.4%) and exotics (9.3%). Firewood usage represents savings to local inhabitants, corresponding to 33% of their monthly earnings, approximate Oak forest, Colombia, wood demand, native forest species, firewood, domestic use of wood.

Development, succession, and stand dynamics of upland oak forests in the Wisconsin Driftless Area: Implications for oak regeneration and management

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Megan L. Buchanan; Kurt F. Kipfmueller; Anthony W. D' Amato

2017-01-01

Throughout the deciduous forests of the eastern United States, oak (Quercus) regeneration has declined in stands historically dominated by oak species. In the Wisconsin Driftless Area, the level of decline in oak regeneration is variable and influenced by stand structural development, historical disturbance regime, abiotic site characteristics, and...

An ecologically based approach to oak silviculture: a synthesis of 50 years of oak ecosystem research in North America

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Daniel C. Dey; Alejandro A. Royo; Patrick H. Brose; Todd F. Hutchinson; Martin A. Spetich; Scott H. Stoleson

2010-01-01

Oak (Quercus L.) is an abundant and widely distributed genus in eastern North America. A history of periodic fire, grazing, canopy disturbance and timber harvesting has favored oak's dominance. But, changes in this regime toward much less fire or complete fire suppression, and selective cutting are causing the successional replacement of oak....

Forecasting the future of coast live oak forests in the face of sudden oak death

Science.gov (United States)

Letty B. Brown; Barbara Allen-Diaz

2006-01-01

Little is known about the potential short- and long-term impacts of sudden oak death (SOD) on forest structure and composition. This study began in 2002 to evaluate the effects of SOD on coast live oak (Quercus agrifolia) - California bay laurel (Umbellularia californica) forests over a gradient of Phytophthora ramorum...

Responses of leaf nitrogen and mobile carbohydrates in different Quercus species/provenances to moderate climate changes.

Science.gov (United States)

Li, M-H; Cherubini, P; Dobbertin, M; Arend, M; Xiao, W-F; Rigling, A

2013-01-01

Global warming and shortage of water have been evidenced in the recent past and are predicted for the future. Climate change will inevitably have considerable impact on plant physiology, growth, productivity and forest ecosystem functions. The present study determined the effects of simulated daytime air warming (+1 to 1.5 °C during the growing season), drought (-40% and -57% of mean precipitation of 728 mm during the 2007 and 2008 growing season, respectively) and their combination, on leaf nitrogen (N) and non-structural carbohydrates (NSC) of two Quercus species (Q. robur and Q. petraea) and provenances (two provenances for each species) grown in two soil types in Switzerland across two treatment years, to test the hypothesis that leaf N and NSC in the more water-sensitive species (Q. robur) and provenances (originating from water-rich locations) will more strongly respond to global warming and water deficit, compared to those in the more drought-tolerant species (Q. petraea) or provenances. No species- and provenance-specific responses in leaf N and NSC to the climate treatment were found, indicating that the results failed to support our hypothesis. The between-species variation of leaf N and NSC concentrations mainly reflected differences in biology of the two species, and the between-provenance variation of N and NSC concentrations apparently mirrored the climate of their origins. Hence, we conclude that (i) the two Quercus species studied are somewhat insensitive, due to their distribution covering a wide geographical and climate range, to moderate climate change within Switzerland, and (ii) a moderate global warming of B1 scenario (IPCC 2007) will not, or at least less, negatively affect the N and carbon physiology in Q. robur and Q. petraea. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

A meta-analysis of the fire-oak hypothesis: Does prescribed burning promote oak reproduction in eastern North America

Science.gov (United States)

Patrick H. Brose; Daniel C. Dey; Ross J. Phillips; Thomas A. Waldrop

2013-01-01

The fire-oak hypothesis asserts that the current lack of fire is a reason behind the widespread oak (Quercus spp.) regeneration difficulties of eastern North America, and use of prescribed burning can help solve this problem. We performed a meta-analysis on the data from 32 prescribed fire studies conducted in mixed-oak forests to test whether they...

The epidemiology of sudden oak death in Oregon forests

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Ebba K. Peterson

2011-01-01

The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in't Veld), causal agent of Sudden Oak Death (SOD) of oaks (Quercus spp.) and tanoaks (Notholithocarpus densiflorus syn. Lithocarpus densiflorus...

[Impact of cork oak management on the ectomycorrhizal fungal diversity associated with Quercus suber in the Mâamora forest (Morocco)].

Science.gov (United States)

Maghnia, Fatima Z; Sanguin, Hervé; Abbas, Younes; Verdinelli, Marcello; Kerdouh, Benaissa; El Ghachtouli, Naima; Lancellotti, Enrico; Bakkali Yakhlef, Salah Eddine; Duponnois, Robin

2017-05-01

The cork oak forest is an ecosystem playing a major role in Moroccan socio-economy and biodiversity conservation. However, this ecosystem is negatively impacted by extensive human- and climate-driven pressures, causing a strong decrease in its distribution and a worsening of the desertification processes. This study aims at characterising the impact of cork oak forest management on a major actor of its functioning, the ectomycorrhizal (EcM) fungal community associated with Quercus suber, and the determination of EcM bio-indicators. The EcM fungal community has been monitored during spring and winter seasons in two sites of the Moroccan Mâamora forest, corresponding to a forest site either impacted by human activities or protected. A significant impact of cork oak forest management on the EcM fungal community has been revealed, with major differences during the summer season. The results confirmed the potential ecological significance of several EcM fungi (e.g., Cenococcum) in the sustainability of the cork oak forest functioning, but also the significant association of certain EcM fungi (Pachyphloeus, Russula, Tomentella) with a perturbation or a season, and consequently to the cork oak forest status or to climatic conditions, respectively. The development of study at the Mediterranean scale may improve the robustness of ecological models to predict the impact of global changes on this emblematic ecosystem of Mediterranean basin. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Responses of northern red oak seedlings to lime and deer exclosure fencing in Pennsylvania

Science.gov (United States)

Robert P. Long; Patrick H. Brose; Stephen B. Horsley

2012-01-01

In Pennsylvania, two hypotheses compete to explain the chronic oak (Quercus spp.) regeneration problem: excessive deer browsing and soil cation depletion. We tested these hypotheses by evaluating the effect of forest liming and deer exclosure fencing on northern red oak (Quercus rubra L.) seedling growth and nutrition in five...

Amplification of North American Red Oak Microsatellite Markers in European White Oaks and Chinese Chestnut

Science.gov (United States)

P. R. Aldrich; M. Jagtap; C. H. Michler; J. Romero-Severson

2003-01-01

We examined the cross-species amplification success of thirty microsatellite markers developed from North American northern red oak (Quercus rubra) in other members of the family Fagaceae. Sixteen of these markers are newly developed and we report primer sequences and amplification conditions here. Twelve of the thirty (40.0%) red oak markers...

Occurrence of Phytophthora plurivora and other Phytophthora species in oak forests of southern Poland and their association with site conditions and the health status of trees.

Science.gov (United States)

Jankowiak, R; Stępniewska, H; Bilański, P; Kolařík, M

2014-11-01

Phytophthora plurivora and other Phytophthora species are known to be serious pathogens of forest trees. Little is known, however, about the presence of P. plurivora in Polish oak forests and their role in oak decline. The aims of this study were to identify P. plurivora in healthy and declining Quercus robur stands in southern Poland and to demonstrate the relationship between different site factors and the occurrence of P. plurivora. In addition, the virulence of P. plurivora and other Phytophthora species was evaluated through inoculations using 2-year-old oak seedlings. Rhizosphere soil was investigated from 39 oak stands representing different healthy tree statuses. The morphology and DNA sequences of the internal transcribed spacer regions (ITS) of the ribosomal DNA and the mitochondrial cox1 gene were used for identifications. P. plurivora, an oak fine root pathogen, was isolated from rhizosphere soil samples in 6 out of 39 stands. Additionally, Phytophthora cambivora, Phytophthora polonica and Phytophthora rosacearum-like were also obtained from several stands. The results showed a significant association between the presence of P. plurivora and the health status of oak trees. Similar relationships were also observed for all identified Phytophthora species. In addition, there was evidence for a connection between the presence of all identified Phytophthora species and some site conditions. Phytophthora spp. occurred more frequently in declining stands and in silt loam and sandy loam soils with pH ≥ 3.66. P. plurivora and P. cambivora were the only species capable of killing whole plants, producing extensive necrosis on seedling stems.

Sessile oak (Quercus petraea agg. Ehrendorfer 1967) rare ...

African Journals Online (AJOL)

STORAGESEVER

2009-09-01

Sep 1, 2009 ... African Journal of Biotechnology Vol. 8 (17), pp. ... Liebl.), Balkan (Quercus dalechampii Ten.) and .... west Serbia; that is on the mountains Goč and Zlatibor. (Map 1 ... supported by the Ministry of Agriculture, Forestry and.

Bird communities of gambel oak: a descriptive analysis

Science.gov (United States)

Andreas Leidolf; Michael L. Wolfe; Rosemary L. Pendleton

2000-01-01

Gambel oak (Quercus gambelii Nutt.) covers 3.75 million hectares (9.3 million acres) of the western United States. This report synthesizes current knowledge on the composition, structure, and habitat relationships of gambel oak avian communities. It lists life history attributes of 183 bird species documented from gambel oak habitats of the western...

In Situ Dark Adaptation Enhances the Efficiency of DNA Extraction from Mature Pin Oak (Quercus palustris Leaves, Facilitating the Identification of Partial Sequences of the 18S rRNA and Isoprene Synthase (IspS Genes

Directory of Open Access Journals (Sweden)

Csengele E. Barta

2017-10-01

Full Text Available Mature oak (Quercus spp. leaves, although abundantly available during the plants’ developmental cycle, are rarely exploited as viable sources of genomic DNA. These leaves are rich in metabolites difficult to remove during standard DNA purification, interfering with downstream molecular genetics applications. The current work assessed whether in situ dark adaptation, to deplete sugar reserves and inhibit secondary metabolite synthesis could compensate for the difficulties encountered when isolating DNA from mature leaves rich in secondary metabolites. We optimized a rapid, commercial kit based method to extract genomic DNA from dark- and light-adapted leaves. We demonstrated that in situ dark adaptation increases the yield and quality of genomic DNA obtained from mature oak leaves, yielding templates of sufficiently high quality for direct downstream applications, such as PCR amplification and gene identification. The quality of templates isolated from dark-adapted pin oak leaves particularly improved the amplification of larger fragments in our experiments. From DNA extracts prepared with our optimized method, we identified for the first time partial segments of the genes encoding 18S rRNA and isoprene synthase (IspS from pin oak (Quercus palustris, whose full genome has not yet been sequenced.

Phytophthora ramorum infection in coast live oaks and Shreve's oaks treated with insecticide to prevent beetle colonization

Science.gov (United States)

Brice A. McPherson; David L. Wood; David M. Rizzo; Pavel Svihra; Steve Tjosvold; Andrew J. Storer; Richard B. Standiford

2006-01-01

As the name implies, sudden oak death, caused by Phytophthora ramorum, kills many, if not most of the coast live oaks, Quercus agrifolia, that become infected (McPherson and others, 2005). Several genera of ambrosia and bark beetles (Coleoptera: Scolytidae) colonize bleeding (infected) trees and are suspected to hasten tree death....

Responses of oaks and tanoaks to the sudden oak death pathogen after 8 y of monitoring in two coastal California forests

Science.gov (United States)

Brice A. McPherson; Sylvia R. Mori; David L. Wood; Maggi Kelly; Andrew J. Storer; Pavel Svihra; Richard B. Standiford

2010-01-01

Sudden oak death, caused by Phytophthora ramorum, is widely established in mesic forests of coastal central and northern California. In 2000, we placed 18 plots in two Marin County sites to monitor disease progression in coast live oaks (Quercus agrifolia), California black oaks (Q. kelloggii), and tanoaks (Lithocarpus densiflorus), the species that are most...

Long-term trends in coast live oak and tanoak stands affected by Phytophthora ramorum canker (Sudden Oak Death)

Science.gov (United States)

Tedmund J. Swiecki; Elizabeth Bernhardt

2010-01-01

Permanent plots were established in 2000 to examine how tree and site factors affect risk of Phytophthora ramorum stem canker (sudden oak death [SOD]) and determine how affected stands change over time due to disease. P. ramorum canker was prevalent in the sampled coast live oak (Quercus agrifolia) or...

Anti nutritional evaluation of the flour of the nipples of holm oak (quercus ilex) and oak cork (quercus suber) Raw and pressure-sealed

International Nuclear Information System (INIS)

El Mahi, F. Z.

2009-01-01

The present study contributes to the development of the food potential of the nipples of oak like new resources likely to be exploited on an industrial scale for their use in animal feeds. Our work relates to two species S of nipples of oak, edible, the holm oak and the other fodder one, the oak cork known for their spontaneousness and their vey significant geographical distribution. (Author)

Genetic hitch-hiking extends the range of coast live oak

Science.gov (United States)

Richard S. Dodd; Zara Afzal-Rafii; Wasima Mayer

2006-01-01

The northernmost range of coast live oak (Quercus agrifolia) is reported from the Ukiah Valley (Mendocino County, California). Here, field observations suggest that hybridization with interior live oak (Q. wislizeni) is important. Elsewhere in northern California, morphology of coast live oak can be highly variable (particularly...

Determining seed moisture in Quercus

Science.gov (United States)

F. T. Bonner

1974-01-01

The air-oven method with drying times 7 to 8 hours shorter than those now prescribed in the ISTA rules proved adequate for determining moisture contents in acorns of several North American oaks. Schedules of 8 hours at 105°C for Quercus muehlenbergii and 9 hours at 105°C for Q.shumardii and Q.nigra gave moisture contents within three percentage points of those obtained...

A field guide to insects and diseases of California oaks

Science.gov (United States)

Tedmund J. Swiecki; Elizabeth A. Bernhardt

2006-01-01

California has more than twenty-five native species, natural hybrids, and varieties of oaks (Quercus species). The form of these oaks ranges from large trees, up to about 25 m tall, to shrubs no taller than about 1.5 m. California's native oaks include representatives of three oak subgroups or subgenera (Table 1). Hybridization only occurs...

Quantitative trait loci for resistance to two fungal pathogens in Quercus robur

Science.gov (United States)

Cécile Robin; Amira Mougou-Hamdane; Jean-Marc Gion; Antoine Kremer; Marie-Laure. Desprez-Loustau

2012-01-01

Powdery mildew, caused by Erysiphe alphitoides (Ascomycete), is the most frequent disease of oaks, which are also known to be host plants for Phytophthora cinnamomi (Oomycete), the causal agent of ink disease. Components of genetic resistance to these two pathogens, infecting either leaves or root and collar, were...

Ectomycorrhizal fungal communities of native and non-native Pinus and Quercus species in a common garden of 35-year-old trees.

Science.gov (United States)

Trocha, Lidia K; Kałucka, Izabela; Stasińska, Małgorzata; Nowak, Witold; Dabert, Mirosława; Leski, Tomasz; Rudawska, Maria; Oleksyn, Jacek

2012-02-01

Non-native tree species have been widely planted or have become naturalized in most forested landscapes. It is not clear if native trees species collectively differ in ectomycorrhizal fungal (EMF) diversity and communities from that of non-native tree species. Alternatively, EMF species community similarity may be more determined by host plant phylogeny than by whether the plant is native or non-native. We examined these unknowns by comparing two genera, native and non-native Quercus robur and Quercus rubra and native and non-native Pinus sylvestris and Pinus nigra in a 35-year-old common garden in Poland. Using molecular and morphological approaches, we identified EMF species from ectomycorrhizal root tips and sporocarps collected in the monoculture tree plots. A total of 69 EMF species were found, with 38 species collected only as sporocarps, 18 only as ectomycorrhizas, and 13 both as ectomycorrhizas and sporocarps. The EMF species observed were all native and commonly associated with a Holarctic range in distribution. We found that native Q. robur had ca. 120% higher total EMF species richness than the non-native Q. rubra, while native P. sylvestris had ca. 25% lower total EMF species richness than non-native P. nigra. Thus, across genera, there was no evidence that native species have higher EMF species diversity than exotic species. In addition, we found a higher similarity in EMF communities between the two Pinus species than between the two Quercus species. These results support the naturalization of non-native trees by means of mutualistic associations with cosmopolitan and novel fungi.

Mexican oaks as a potential non-timber resource for Kombucha beverages

OpenAIRE

Vázquez-Cabral, Blanca D.; Moreno-Jiménez, Martha R.; Rocha-Guzmán, Nuria E.; Gallegos-Infante, José A.; González-Herrera, Silvia M.; Gamboa-Gómez, Claudia I.; González-Laredo, Rubén F.

2016-01-01

Abstract: Oaks (Quercus spp.) are some of the world's most important and abundant trees in nearly all temperate forests of the northern hemisphere. There are two diversity centers for this genus: one is in Southeast Asia, and the other is in Mexico. Studies on the use of oak have mainly highlighted its timber applications. However, its non-timber value is still unappreciated. Ethnobotanical tradition shows infusions from Quercus leaves, alone or in combination with other plants, which have an...

Seed production differences of the Andean oak Quercus Humboldtii Bonpl. in two Andean forests of the Colombian Eastern Cordillera

International Nuclear Information System (INIS)

Gonzalez Melo, Andres; Parrado Rosselli Angela

2010-01-01

Knowledge of mechanisms of tree species reproduction under natural situations including fruit and seed production patterns is very important for forest management strategies. Considering the influence of abiotic factors such as soil characteristics, humidity and rainfall on fruiting phenology, we studied fruit production patterns of the Andean oak (Quercus humboldtii: Fagaceae) in two forest sites of the Colombian Eastern Cordillera (Cachalu and Patios Altos), under contrasting environmental conditions. At both sites, we monitored monthly fruit production of 15 trees in Cachalu and 11 in Patios Altos using fruit/seed traps placed under the tree crowns. In each site soil cores were extracted below the litter layer 20 cm depth, and soil characteristics and nutrients were analyzed. In general, trees in Cachalu produced more fruits than in Patios Altos, as well as mean fruit mass (wet and dry weight) was significantly higher in Cachalu. At both sites, oak fruiting peaked from April to May, when the highest rainfall occurs. We found positive correlations between fruit production and rainfall one month prior. High phosphorus (P) and potassium (K) were the main variables for explaining the high production. In contrast, high aluminum (Al) contents explained the low production found in Patios Altos. We discuss the importance of including fruit production for oak management strategies, such as restoration and reforestation programs.

High rates of gene flow by pollen and seed in oak populations across Europe.

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Sophie Gerber

Full Text Available Gene flow is a key factor in the evolution of species, influencing effective population size, hybridisation and local adaptation. We analysed local gene flow in eight stands of white oak (mostly Quercus petraea and Q. robur, but also Q. pubescens and Q. faginea distributed across Europe. Adult trees within a given area in each stand were exhaustively sampled (range [239, 754], mean 423, mapped, and acorns were collected ([17,147], 51 from several mother trees ([3], [47], 23. Seedlings ([65,387], 178 were harvested and geo-referenced in six of the eight stands. Genetic information was obtained from screening distinct molecular markers spread across the genome, genotyping each tree, acorn or seedling. All samples were thus genotyped at 5-8 nuclear microsatellite loci. Fathers/parents were assigned to acorns and seedlings using likelihood methods. Mating success of male and female parents, pollen and seed dispersal curves, and also hybridisation rates were estimated in each stand and compared on a continental scale. On average, the percentage of the wind-borne pollen from outside the stand was 60%, with large variation among stands (21-88%. Mean seed immigration into the stand was 40%, a high value for oaks that are generally considered to have limited seed dispersal. However, this estimate varied greatly among stands (20-66%. Gene flow was mostly intraspecific, with large variation, as some trees and stands showed particularly high rates of hybridisation. Our results show that mating success was unevenly distributed among trees. The high levels of gene flow suggest that geographically remote oak stands are unlikely to be genetically isolated, questioning the static definition of gene reserves and seed stands.

Floristic diversity of posavina's floodplain forests in serbia and their wider geographical context

International Nuclear Information System (INIS)

Jurisic, B.; Puvaca, N.

2014-01-01

In order to detect floristic divergence of analysed stands we applied TWINSPAN classification and ordinary Correspondence Analysis. Both analyses have shown an almost identical result of floristic composition, where 114 studied samples were grouped into seven association groups at the third twinspan classification level. These seven groups, successively from the most humid to most dry, comprising two large groups of plant associations, completely corresponding to two alliances: Forest of Pedunculate Oak and Alder and Forest of Pedunculate Oak and Hornbeam. SIMPER procedure have shown tahat within the first 20.51% of cumulative contribution, the floristic divegence among the studied forest stands includes 13 taxa: Carpinus betulus., Fraxinus angustifolia, Quercus cerris, Amorpha fruticosa, Convallaria majalis, Crataegus oxyacantha, Quercus robur, Lysimachia nummularia, Tamus communis, Galium aparine, Rubus caesius, Ulmus carpinifolia and Ajuga reptans. ANOSIM analysis were used to determine the degree of floristic discontinuity. It was largest between forest of Pedunculate Oak, Hornbeam and Turkey Oak and forest of Pedunculate Oak and Ash (statistics R = 0.8824 (p<0.001)). The lowest floristic dissimilarity was between the forest of Pedunculate Oak, Hornbeam and Turkey Oak and forest of Pedunculate Oak, Hornbeam and Turkey Oak with Lindens, where R = 0.2009 (p<0.01). Posavina floodplain forests in Serbia generally show good agreement with analogous communities in neighbouring countries in the Balkan peninsula and Central Europe. (author)

Variation of Oriental Oak (Quercus variabilis Leaf δ13C across Temperate and Subtropical China: Spatial Patterns and Sensitivity to Precipitation

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Baoming Du

2015-06-01

Full Text Available The concentration of the carbon-13 isotope (leaf δ13C in leaves is negatively correlated with the mean annual precipitation (MAP atlarge geographical scales. In this paper, we explain the spatial pattern of leaf δ13C variation for deciduous oriental oak (Quercus variabilis Bl. across temperate and subtropical biomes and its sensitivity to climate factors such as MAP. There was a 6‰ variation in the leaf δ13C values of oak with a significant positive correlation with latitude and negative correlations with the mean annual temperature (MAT and MAP. There was no correlation between leaf δ13C and altitude or longitude. Stepwise multiple regression analyses showed that leaf δ13C decreased 0.3‰ per 100 mm increase in MAP. MAP alone could account for 68% of the observed variation in leaf δ13C. These results can be used to improve predictions for plant responses to climate change and particularly lower rainfall.

Managing an oak decline crisis in Oakville, Ontario: lessons learned

Science.gov (United States)

Peter A. Williams; John W. McNeil; Kurt W. Gottschalk; Robert A. Haack

2013-01-01

The town of Oakville, Ontario, is located along the north shore of Lake Ontario between Toronto and Hamilton. In the fall of 2002, significant oak (Quercus spp.) mortality was observed at Oakville's Iroquois Shoreline Woods Park, an environmentally significant forest remnant noted for its oak-dominated forests. Investigations suggested that oak...

An investigation on forage yield capacity of kermes oak (Quercus coccifera L.) and grazing planning of Mediterranean maquis scrublands for traditional goat farming.

Science.gov (United States)

Tolunay, Ahmet; Adıyaman, Elif; Akyol, Ayhan; İnce, Duygu; Türkoğlu, Türkay; Ayhan, Veysel

2014-01-01

This study investigated grazing capacities of maquis scrubland and preparation principles of grazing management in forest resources. Kermes oak (Quercus coccifera L.), which is widespread as a main shrub species in maquis vegetation in Turkey, and pure hair goats (Capra hircus L.) feeding on shoots and leaves of this shrub were selected for study. The study was conducted in two stages. Green leaf and shoot samples were taken from kermes oaks in the first stage and the amount of green herbage yield (g ∗ m(-1)) and dry matter yield (kg ∗ ha(-1)) that may be obtained per unit area from these samples was identified. The considered amount of dry matter consumed by pure hair goats daily and the number of goats being fed within 1 year on land of 1 ha according to different land coverage rates of kermes oaks (goat head ∗ ha ∗ yr) were calculated. In the second stage, grazing capacities of sample areas where kermes oak spread were identified and compared with the grazing plan prepared by the forestry administration for this area. Forage yield variance according to land coverage rates of maquis scrublands should be considered when determining optimum animal numbers for grazing per area for sustainable goat farming.

An Investigation on Forage Yield Capacity of Kermes Oak (Quercus coccifera L. and Grazing Planning of Mediterranean Maquis Scrublands for Traditional Goat Farming

Directory of Open Access Journals (Sweden)

Ahmet Tolunay

2014-01-01

Full Text Available This study investigated grazing capacities of maquis scrubland and preparation principles of grazing management in forest resources. Kermes oak (Quercus coccifera L., which is widespread as a main shrub species in maquis vegetation in Turkey, and pure hair goats (Capra hircus L. feeding on shoots and leaves of this shrub were selected for study. The study was conducted in two stages. Green leaf and shoot samples were taken from kermes oaks in the first stage and the amount of green herbage yield (g*m−1 and dry matter yield (kg*ha−1 that may be obtained per unit area from these samples was identified. The considered amount of dry matter consumed by pure hair goats daily and the number of goats being fed within 1 year on land of 1 ha according to different land coverage rates of kermes oaks (goat head*ha*yr were calculated. In the second stage, grazing capacities of sample areas where kermes oak spread were identified and compared with the grazing plan prepared by the forestry administration for this area. Forage yield variance according to land coverage rates of maquis scrublands should be considered when determining optimum animal numbers for grazing per area for sustainable goat farming.

Impact of the goldspotted oak borer, Agrilus auroguttatus, on the health of coast live oak before and after treatment with two systemic insecticides

Science.gov (United States)

Yigen Chen; Mary L. Flint; Tom W. Coleman; Joseph J. Doccola; Donald M. Grosman; David L. Wood; Steven J. Seybold

2015-01-01

BACKGROUND: The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego County, California. From two sites in the core area of the infestation, we report a 2.5 year investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic...

Elemental concentrations in foliage of red maple, red oak, and white oak in relation to atmospheric deposition in Pennsylvania

Science.gov (United States)

D. D. Davis; J. M. Skelly; B. L. Nash

1995-01-01

Foliage was sampled in June and late August-early September in 1988 and 1989 from the outer crowns of codominant red maple (Acer rubrum L.), northern red oak (Quercus rubra L.), and white oak (Q. alba L.) trees in forest stands along an atmospheric deposition gradient in north-central Pennsylvania. Leaf samples...

Consequences of Phytophthora ramorum infection in coast live oaks

Science.gov (United States)

Brice McPherson; David L. Wood; Sylvia R. Mori; Pavel Svihra; Richard B. Standiford; N. Maggi. Kelly

2008-01-01

Sudden oak death, caused by Phytophthora ramorum, has infected and killed large numbers of oaks (Quercus spp.) and tanoaks (Lithocarpus densiflorus) in California since the mid 1990s. Since March 2000 we have been investigating the interactions between patterns of disease progression and...

Attack pattern of Platypus koryoensis (Coleoptera: Curculionidae: Platypodidae) in relation to crown dieback of Mongolian oak in Korea

Science.gov (United States)

Jung-Su Lee; Robert A. Haack; Won Il. Choi

2011-01-01

The ambrosia beetle, Platypus koryoensis (Murayama), vectors the Korean oak wilt (KOW) pathogen, Raffaelea quercus-mongolicae K.H. Kim, Y.J. Choi, & H.D. Shin, in Korea, which is highly lethal to Mongolian oak, Quercus mongolica Fisch., and is considered a major threat to forest ecosystem health. We...

Molecular diversity among Turkish oaks ( QUERCUS ) using random ...

African Journals Online (AJOL)

Turkey is one of the most important region of the world according to oak species number and variation. In this study, species belonging to evergreen oaks in Turkey were investigated to solve taxonomic problems and to design the limit of taxa by using random amplified polymorphic DNA (RAPD) data. Here, three species of ...

Effects of cadmium on cork oak (Quercus suber L.) plants grown in hydroponics.

Science.gov (United States)

Gogorcena, Yolanda; Larbi, Ajmi; Andaluz, Sofia; Carpena, Ramón O; Abadía, Anunciación; Abadía, Javier

2011-12-01

Cork oak (Quercus suber L.) is an autochthonous tree species that is being used for reforestation in heavy-metal-contaminated areas in Spain. A hydroponics experiment was carried out to characterize the effects of Cd on several morphological and physiological parameters in this species, including shoot length, nutrient concentrations and allocation in different organs, leaf pigment concentrations, photosynthetic efficiency, root ferric chelate reductase (FCR) activity and organic acid concentrations in xylem sap. Four different Cd treatments were applied, adding Cd chelated with EDTA or as chloride salt at two different concentrations (10 and 50 µM Cd). After 1 month of Cd treatment, plant growth was significantly inhibited in all treatments. Results indicate that Cd accumulates in all organs 7- to 500-fold when compared with control plants. The highest Cd concentration was found in the 50 µM CdCl(2) treatment, which led to concentrations of ~30, 123 and 1153 µg Cd g(-1) dry weight in leaves, stems and roots, respectively. In the strongest Cd treatments the concentrations of P and Ca decreased in some plant parts, whereas the Mn leaf concentrations decreased with three of the four Cd treatments applied. The concentrations of chlorophyll and carotenoids on an area basis decreased, whereas the (zeaxanthin plus antheraxanthin)/(total violaxanthin cycle carotenoids) ratio and the non-photochemical quenching increased significantly in all Cd treatments. Cadmium treatments caused significant increases in the activity of the enzyme FCR in roots and in the concentrations of organic acids in xylem sap. Some of the physiological changes found support the fact that Cd induces a deficiency of Fe in cork oak, although the plant Fe concentrations were not reduced significantly. At higher concentrations the effects of Cd were more pronounced, and were more marked when Cd was in the free ion form than when present in the form of Cd-EDTA.

Anti nutritional evaluation of the flour of the nipples of holm oak (quercus ilex) and oak cork (quercus suber) Raw and pressure-sealed

Energy Technology Data Exchange (ETDEWEB)

El Mahi, F. Z.

2009-07-01

The present study contributes to the development of the food potential of the nipples of oak like new resources likely to be exploited on an industrial scale for their use in animal feeds. Our work relates to two species S of nipples of oak, edible, the homl oak and the other fodder one, the oal cork known for their spontaneousness and their vey significant geographical distribution. (Author)

Population-Level Differentiation in Growth Rates and Leaf Traits in Seedlings of the Neotropical Live Oak Quercus oleoides Grown under Natural and Manipulated Precipitation Regimes

Directory of Open Access Journals (Sweden)

Jose A. Ramírez-Valiente

2017-05-01

Full Text Available Widely distributed species are normally subjected to spatial heterogeneity in environmental conditions. In sessile organisms like plants, adaptive evolution and phenotypic plasticity of key functional traits are the main mechanisms through which species can respond to environmental heterogeneity and climate change. While extended research has been carried out in temperate species in this regard, there is still limited knowledge as to how species from seasonally-dry tropical climates respond to spatial and temporal variation in environmental conditions. In fact, studies of intraspecific genetically-based differences in functional traits are still largely unknown and studies in these ecosystems have largely focused on in situ comparisons where environmental and genetic effects cannot be differentiated. In this study, we tested for ecotypic differentiation and phenotypic plasticity in leaf economics spectrum (LES traits, water use efficiency and growth rates under natural and manipulated precipitation regimes in a common garden experiment where seedlings of eight populations of the neotropical live oak Quercus oleoides were established. We also examined the extent to which intraspecific trait variation was associated with plant performance under different water availability. Similar to interspecific patterns among seasonally-dry tropical tree species, live oak populations with long and severe dry seasons had higher leaf nitrogen content and growth rates than mesic populations, which is consistent with a “fast” resource-acquisition strategy aimed to maximize carbon uptake during the wet season. Specific leaf area (SLA was the best predictor of plant performance, but contrary to expectations, it was negatively associated with relative and absolute growth rates. This observation was partially explained by the negative association between SLA and area-based photosynthetic rates, which is contrary to LES expectations but similar to other recent

Coarse woody debris metrics in a California oak woodland

Science.gov (United States)

William D. Tietje; Michael A. Hardy; Christopher C. Yim

2015-01-01

Little information is available on the metrics of coarse woody debris (CWD) in California oak woodland, most notably at the scale of the stand and woodland type. In a remote part of the National Guard Post, Camp Roberts, that has not burned in over a half century, we tallied 314 pieces of CWD in a blue oak (Quercus douglasii)-coast live oak (

Specific polyphenols and tannins are associated with defense against insect herbivores in the tropical oak Quercus oleoides.

Science.gov (United States)

Moctezuma, Coral; Hammerbacher, Almuth; Heil, Martin; Gershenzon, Jonathan; Méndez-Alonzo, Rodrigo; Oyama, Ken

2014-05-01

The role of plant polyphenols as defenses against insect herbivores is controversial. We combined correlative field studies across three geographic regions (Northern Mexico, Southern Mexico, and Costa Rica) with induction experiments under controlled conditions to search for candidate compounds that might play a defensive role in the foliage of the tropical oak, Quercus oleoides. We quantified leaf damage caused by four herbivore guilds (chewers, skeletonizers, leaf miners, and gall forming insects) and analyzed the content of 18 polyphenols (including hydrolyzable tannins, flavan-3-ols, and flavonol glycosides) in the same set of leaves using high performance liquid chromatography and mass spectrometry. Foliar damage ranged from two to eight percent per region, and nearly 90% of all the damage was caused by chewing herbivores. Damage due to chewing herbivores was positively correlated with acutissimin B, catechin, and catechin dimer, and damage by mining herbivores was positively correlated with mongolinin A. By contrast, gall presence was negatively correlated with vescalagin and acutissimin B. By using redundancy analysis, we searched for the combinations of polyphenols that were associated to natural herbivory: the combination of mongolinin A and acutissimin B had the highest association to herbivory. In a common garden experiment with oak saplings, artificial damage increased the content of acutissimin B, mongolinin A, and vescalagin, whereas the content of catechin decreased. Specific polyphenols, either individually or in combination, rather than total polyphenols, were associated with standing leaf damage in this tropical oak. Future studies aimed at understanding the ecological role of polyphenols can use similar correlative studies to identify candidate compounds that could be used individually and in biologically meaningful combinations in tests with herbivores and pathogens.

Conservation and fruit biology of Sichou oak (Quercus sichourensis, Fagaceae – A critically endangered species in China

Directory of Open Access Journals (Sweden)

Ke Xia

2016-10-01

Full Text Available Several conservation programs have been started for the critically endangered Sichou oak (Quercus sichourensis since 2007. These programs include detailed field investigations, seedling cultivation and research on the fruit biology of the species. In this study, we first report on the five mature individual trees found in our 9-year field investigation. Thus far, a total of 10 mature individuals have been recorded. All Q. sichourensis trees are healthy and most produce healthy acorns. Acorns of Q. sichourensis are large with dry masses of 8.0–14.0 g. These acorns had high moisture contents at collection and died shortly after (7–28 d when dried with silica gel. Characteristics of Q. sichourensis acorns varied between populations. Compared with the acorns from Funing, the acorns collected from Ceheng were bigger, more viable (germination percentage was up to 96%, less sensitive to desiccation, and germinated faster. Q. sichourensis occurs in regions with a distinct 5–6 month dry season. Habitat degradation is largely responsible for the rareness of Quercus sichorensis, but desiccation sensitivity of the acorns may also limit the regeneration of the species and potentially lead to its continued rareness. As a species with extremely small populations (PSESP, Q. sichourensis is facing high risk of extinction and should be defined as a Critically Endangered species in the global IUCN Red List.

Cork oak woodlands patchiness

DEFF Research Database (Denmark)

Costa, Augusta; Madeira, Manuel; Plieninger, Tobias

2014-01-01

The cork oak (Quercus suber L.) woodlands of the agroforestry landscapes of Southwestern Iberia are undergoing drastic change due to severe natural and anthropogenic disturbances. These may eventually result in woodland loss or deforestation, the final step of an ongoing process of woodland degra...

Chemical ecology of sudden oak death/ambrosia beetle interactions

Science.gov (United States)

Frances S. Ockels; Pierluigi Bonello; Brice McPherson; David L. Wood

2006-01-01

Coast live oaks, Quercus agrifolia, infected with Phytophthora ramorum in California produce a characteristic sequence of symptoms and signs. Ambrosia beetles consistently tunnel into the bark of bleeding cankers in naturally infected trees. In field monitoring conducted since 2000, every bleeding coast live oak that subsequently...

The role of large container seedlings in afforesting oaks in bottomlands

Science.gov (United States)

Daniel C. Dey; John M. Kabrick; Michael Gold

2006-01-01

We planted large container (RPM®) and 1-0 bareroot seedlings of pin oak (Quercus palustris Muenchh.) and swamp white oak (Q. bicolor Willd.) in crop fields in the Missouri River floodplain. We also evaluated the benefits of soil mounding and a grass (Agrostis gigantea Roth) cover crop. RPM®) oak seedlings had significantly greater...

Diagnosis and Management of Phytophthora ramorum canker in canyon live oak, an atypical bole canker host

Science.gov (United States)

Tedmund J. Swiecki; Elizabeth Bernhardt; Kamyar Aram; David Rizzo

2013-01-01

Diagnosis of sudden oak death (SOD) in tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh) and susceptible red/black oak species (coast live oak, Quercus agrifolia Née; Shreve oak, Q. parvula Greene var. shrevei (C.H. Mull.) Nixon; California...

Heritability of first-order lateral root number in Quercus: implication for artificial regeneration of stands

Science.gov (United States)

Paul P. Kormanik; Shi-Jean S. Sung; Taryn L. Kormanik; Stanley L. Zarnoch; Scott Schlarbaum

2000-01-01

Natural regeneration of oak (Quercus) species in the USA has been easy to obtain on the lower quality xeric sites (site index less than or equal to 20 m at age 50) by developing advanced oak reproduction before stands are harvested. This approach has not been successful with Q. rubra, Q. pagoda, or Q. alba...

Transcriptome analysis in oak uncovers a strong impact of endogenous rhythmic growth on the interaction with plant-parasitic nematodes.

Science.gov (United States)

Maboreke, Hazel R; Feldhahn, Lasse; Bönn, Markus; Tarkka, Mika T; Buscot, Francois; Herrmann, Sylvie; Menzel, Ralph; Ruess, Liliane

2016-08-12

Pedunculate oak (Quercus robur L.), an important forest tree in temperate ecosystems, displays an endogenous rhythmic growth pattern, characterized by alternating shoot and root growth flushes paralleled by oscillations in carbon allocation to below- and aboveground tissues. However, these common plant traits so far have largely been neglected as a determining factor for the outcome of plant biotic interactions. This study investigates the response of oak to migratory root-parasitic nematodes in relation to rhythmic growth, and how this plant-nematode interaction is modulated by an ectomycorrhizal symbiont. Oaks roots were inoculated with the nematode Pratylenchus penetrans solely and in combination with the fungus Piloderma croceum, and the systemic impact on oak plants was assessed by RNA transcriptomic profiles in leaves. The response of oaks to the plant-parasitic nematode was strongest during shoot flush, with a 16-fold increase in the number of differentially expressed genes as compared to root flush. Multi-layered defence mechanisms were induced at shoot flush, comprising upregulation of reactive oxygen species formation, hormone signalling (e.g. jasmonic acid synthesis), and proteins involved in the shikimate pathway. In contrast during root flush production of glycerolipids involved in signalling cascades was repressed, suggesting that P. penetrans actively suppressed host defence. With the presence of the mycorrhizal symbiont, the gene expression pattern was vice versa with a distinctly stronger effect of P. penetrans at root flush, including attenuated defence, cell and carbon metabolism, likely a response to the enhanced carbon sink strength in roots induced by the presence of both, nematode and fungus. Meanwhile at shoot flush, when nutrients are retained in aboveground tissue, oak defence reactions, such as altered photosynthesis and sugar pathways, diminished. The results highlight that gene response patterns of plants to biotic interactions, both

Predicting oak density with ecological, physical, and soil indicators

Science.gov (United States)

Callie Jo Schweitzer; Adrian A. Lesak; Yong Wang

2006-01-01

We predicted density of oak species in the mid-Cumberland Plateau region of northeastern Alabama on the basis of basal area of tree associations based on light tolerances, physical site characteristics, and soil type. Tree basal area was determined for four species groups: oaks (Quercus spp.), hickories (Carya spp.), yellow-poplar...

Seasonal variability of interception and water wettability of common oak leaves

Directory of Open Access Journals (Sweden)

Anna Klamerus-Iwan

2017-07-01

Full Text Available Wettability of leaves and the resulting amount of interception loss of tree crowns is an important component of the atmosphere-tree stand-soil system balance. In the study, we hypothesized that changes occurring in leaves during the vegetation period can significantly affect the amount of rainwater retained by plants and wettability of leaves which is expressed by the contact angle between drops and leaves. We evaluated the hypothesis based on measurement series, which combined direct spraying of leaves with water at different stages of development at a constant temperature with observations made with an electron scanner which was used to determine changes occurring within a leaf, while the photographic method was used to analyze the contact angle of drops. The study involved common oak (Quercus robur. Samples of twigs derived from this species were collected in the area of Przedbórz (Poland forest district, in particular from the trees with well-developed crowns. Twigs were collected from 10 trees of similar age (35–40 years. The resulting database contained experimental data on changes of raindrop adhesion on oak leaves throughout the growing season. The internal contact angle of drops was within the range of 150° on the upper side of the leaf and 160° on the underside in May, up to 15° and 35° in November on the upper and underside of the leaves. Loss of interception was established at 6% at the beginning of the growing season up to 22% in autumn. It was concluded that the wettability and the level of interception increases in line with the age of a leaf.

Lighting intensity of the soilsurface and restocking of oak groves

Science.gov (United States)

Slepykh, Victor; Zubko, Anna; Povolotckaia, Nina

2016-04-01

Oak groves of Caucasian Mineral Vody region (CMVR) possess a high ecological and balneological potential which defines the significance of their preservation and reproduction [1]. The role assessment of lighting intensity on renewal of oak groves was carried out on four trial squares (ts) in natural sixty-seven years old forest stand with prevalence of English oak (Quercus robur L.) with unimodal sity (type of the habitat - C1). The illumination was measured at the grass level by the universal measuring instrument of meteoparameters ATT-9508 with an illumination sensor of ATA-1591. The assessment of reforestation was carried out according to the established standards [2]. In the winter of 2005 there was conducted a selecting cutting cabin of the forest stand according to a local method on ts2 with intensity 30%, on ts4 - 50% after which the illumination on the soil surface in relation to illumination of an open place in the summer of 2005 increased from 4.9% to 33.9% on ts2, and from 5.9% to 24.4% on ts4. But by 2014 the illumination decreased till 3.0% on ts2, till 5.4% on ts4 because of an intensive soil grassing down. The control was carried out by ts1 and ts3 on which from 2005 to 2014 the illumination of the soil surface decreased from 4 to 2% as a result of the development of all storeys. As a result due to an intensive soil grassing-down, the total quantity of young oak trees decreased from 2005 to 2014 from 25.6 thousand pcs/ha to 5.9 thousand pcs/ha on ts2; on from 17.3 thousand pcs/ha to 4.0 thousand pcs/ha on ts4. At the same time the total quantity of young oak trees on control squares increased respectively for 1.4% (from 18.8 thousand pcs/ha to 19.1 thousand pcs/ha) on ts1, for 38.7% (from 25.2 thousand pcs/ha to 41.1 thousand pcs/ha). The experiment showed that small young oak trees perishes in the first years of their life from a lack of light and competition from grasland vegetation without providing successful reforestation. Conclusion. So it is

Regeneration of native California oaks in the forest zone [Abstract

Science.gov (United States)

P.M. McDonald

1999-01-01

The two native California oaks in the forest zone of California are California black oak (Quercus kelloggii Newb.) and tanoak (Lithocarpus densiflorus [Hook. and Arn.] Rehd.). Both are ancient species with many adaptations to withstand California's Mediterranean climate, but some weaknesses as well. Both sprout vigorously...

Soil carbon accumulation and nitrogen retention traits of four tree species grown in common gardens

DEFF Research Database (Denmark)

Gurmesa, Geshere Abdisa; Schmidt, Inger Kappel; Gundersen, Per

2013-01-01

explored. Effects of four tree species on soil C and N stocks and soil water nitrate concentration below the root zone were evaluated in a common garden design replicated at eight sites in Denmark. The tree species were beech (Fagus sylvatica L.), oak (Quercus robur L.), larch (Larix leptolepis Kaempf......), and Norway spruce (Picea abies (L) Karst.). After four decades, there were significant differences in forest floor C stocks among all four species, and C stocks increased consistently in the order oak Forest floor N stocks only...... differed significantly between conifers and broadleaves. The observed differences in forest floor C and N stocks were attributed to differences in litter turnover rates among the tree species. Mineral soil C stocks were significantly higher in stands of Norway spruce than in stands of oak and beech while...

Effects of disking, bedding, and subsoiling on survival and growth of three oak species in central Mississippi

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J. Paul Jeffreys; Emily B. Schultz; Thomas G. Matney; W. Cade Booth; Jason M. Morris

2010-01-01

A replicated split-plot design experiment to evaluate the effects of three site preparation methods (disking, bedding, and subsoiling plus bedding) on survival and growth of three oak species (cherrybark, Quercus pagoda Raf.; Shumard, Quercus shumardii Buckl.; and Nuttall, Quercus texana Buckl.) was established...

Searching for early-warning signals of impending dieback and death in Mediterranean oaks

Science.gov (United States)

Colangelo, Michele; Ripullone, Francesco; Julio Camarero, Jesus; De Micco, Veronica; Gazol, Antonio; Gentilesca, Tiziana; Borghetti, Marco

2017-04-01

In recent decades, forest dieback episodes have been recorded worldwide affecting different tree species. In particular, several cases of widespread dieback and increased mortality rates have been described for Mediterranean oak (Quercus spp.) species. These dieback cases are revealing the high vulnerability of Mediterranean oaks, manifested as a loss in tree vigour (leaf shedding, canopy and shoot dieback), growth decline and sometimes tree death, as a consequence of temperatures rising at unprecedented rates and drying trends. However, in the wake of the so-called 'oak decline phenomenon', the attention on these species has generally been limited, perhaps because they are often regarded as well-adapted to the dry conditions typical of Mediterranean areas. Indeed, according to recent studies, the reduced size, the ability to sprout and the anisohydric behavior of Mediterranean oak species (reduced control of water loss and high stomatal conductance rates) would make them better adapted to withstand heat and drought stress then taller and non-sprouting isohydric species (e.g. conifer, with strict control of water loss by closing stomata). Here, we investigated the vulnerability of Mediterranean oaks by comparing neighboring living and recently dead trees in species with low (Q. pubescens), intermediate (Q. cerris, Q. frainetto) and high (Q. robur) sensitivity to water shortage. We analysed changes in tree vigour using tree-ring width and functional wood anatomical traits as proxies to search for early-warning signals of dieback, in connection with the main proposed dieback mechanisms (hydraulic failure and/or carbon starvation). We also modeled the probability of tree death as a function of tree size (diameter, height) by quantifying recent changes in growth and wood anatomy along tree-ring series. Contrary to the general concept that trees tend to experience increasing cavitation risk with increasing height, our studies show that smaller oaks are more prone to die

Ecology and management of oak woodlands and savannas in the southwestern Borderlands Region

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Gerald J. Gottfried; Peter F. Ffolliott

2013-01-01

Management of the Madrean oak woodlands and the less dense and ecologically different oak savannas must be based on sound ecological information. However, relatively little is known about the Madrean oak ecosystems in spite of the fact that they cover about 80,000 km2 in the southwestern United States and northern Mexico. Emory oak (Quercus emoryi), the dominant tree...

Evidence of the dynamic response of housing values to a sudden oak death infestation

Science.gov (United States)

Kent F. Kovacs; Thomas P. Holmes; Jeffrey E. Englin; Janice. Alexander

2010-01-01

Sudden oak death (SOD), caused by the non-indigenous forest pathogen Phytophthora ramorum, causes substantial mortality in coast live oak (Quercus agrifolia) and several other oak species on the Pacific Coast of the United States. Quasi-experimental hedonic models examine the effect of SOD on property...

Single-tree harvesting reduces survival and growth of oak stump sprouts in the Missouri Ozark Highlands

Science.gov (United States)

Daniel C. Dey; Randy G. Jensen; Michael J. Wallendorf

2008-01-01

Regeneration and recruitment into the overstory is critical to the success of using uneven-aged systems to sustain oak forests. We evaluated survival and growth of white oak (Quercus alba L.), black oak (Q. velutina Lam.), and scarlet oak (Q. coccinea Muenchh.) stump sprouts 10 years after harvesting Ozark...

Influence of Scarification on the Germination Capacity of Acorns Harvested from Uneven-Aged Stands of Pedunculate Oak (Quercus robur L.

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Zdzisław Kaliniewicz

2018-02-01

Full Text Available Scarification involves the partial removal of the seed coat on the side of the hilum, opposite the radicle, to speed up germination in acorns. The aim of this study was to determine the influence of scarification on the germination capacity of pedunculate oak acorns, selected and prepared for sowing. The diameter, length and mass of acorns were measured before and after scarification in four batches of acorns harvested from uneven-aged trees (76, 91, 131 and 161 years. The measured parameters were used to determine the correlations between acorn dimensions and mass, and to calculate the dimensional scarification index and the mass scarification index in acorns. Individual complete and scarified acorns from every batch were germinated on sand and peat substrate for 28 days. The analyzed acorns were characterized by average size and mass. Scarification decreased acorn mass by around 22% and acorn length by around 31% on average. Scarification and the elimination of infected acorns increased germination capacity from around 64% to around 81% on average. Acorns can be divided into size groups before scarification to obtain seed material with varied germination capacity. Larger acorns with higher germination capacity can be used for sowing in container nurseries, whereas smaller acorns with lower germination capacity can be sown in open-field nurseries.

Relationship between resistance to Phytophthora ramorum and constitutive phenolic chemistry in coast live oaks and northern red oaks

Science.gov (United States)

Annemarie M. Nagle; Matteo Garbelotto; Brice McPherson; David L. Wood; Pierluigi. Bonello

2010-01-01

Phytophthora ramorum causes lethal canker diseases and extensive mortality in coast live oak (CLO) (Quercus agrifolia) and tanoak (Lithocarpus densiflorus). No practical controls are available for this disease in non-urban environments. Therefore, characterization of natural resistance is highly...

Development of northern red oak rooted cutting and enrichment planting systems

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Matthew H. Gocke; Jamie Schuler; Daniel J. Robison; Barry Goldfarb

2005-01-01

Enrichment planting may provide an efficient means to establish elite northern red oak (Quercus rubra L.) genotypes in recently harvested natural forests. However, planting northern red oak (NRO) seedlings into natural stands has proven difficult in the past, especially when competition and other stress factors are not controlled.

A spatial statistical analysis of cork oak competition in two Portuguese silvopastoral systems

NARCIS (Netherlands)

Paulo, M.J.; Stein, A.; Tomé, M.

2002-01-01

This paper considers competition among cork oaks (Quercus suber L.) at three plots in two representative Portuguese stands. It uses spatial point pattern functions to describe densities and quantify differences among stands. Relations between cork oak characteristics and indices measuring intertree

Myxomycetes from the bark of the evergreen oak Quercus ilex

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Wrigley de Basanta, Diana

1998-06-01

Full Text Available The results of 81 moist chamber cultures of bark from living Quercus ilex trees are reponed. A total of 37 taxa are cited, extending the number of species found on this substrate to 55. The presence of Licea deplanata on the Iberian Península is confirmed. Seven new records are included for the province of Madrid. Some data are contributed on species frequency and incubation times.Se presentan los resultados de 81 cultivos en cámara húmeda de corteza de Quercus ilex vivo. Se citan 37 táxones, que amplían a 55 el número de especies de mixomicetes encontrados sobre este sustrato. Se confirma la presencia en la Península Ibérica de Licea deplanata, y se incluyen siete nuevas citas para la provincia de Madrid. Se aportan datos sobre frecuencia de aparición y tiempos de incubación de algunas especies.

Blue Oak Canopy Effect on Seasonal Forage Production and Quality

Science.gov (United States)

William E. Frost; Neil K. McDougald; Montague W. Demment

1991-01-01

Forage production and forage quality were measured seasonally beneath the canopy of blue oak (Quercus douglasii) and in open grassland at the San Joaquin Experimental Range. At the March and peak standing crop sampling dates forage production was significantly greater (p=.05) beneath blue oak compared to open grassland. At most sampling dates, the...

The status of oak and hickory regeneration in forests of Virginia

Science.gov (United States)

Anita K. Rose

2008-01-01

Evidence suggests that eastern U.S. forests dominated by oak (Quercus spp.) and hickory (Carya spp.) may be shifting to more maple- (Acer spp.) and mixed-species dominated forests. Data from the U.S. Forest Service Forest Inventory and Analysis program were used to describe the status of oak and hickory...

Analysis of cyclitols in different Quercus species by gas chromatography-mass spectrometry.

Science.gov (United States)

Rodríguez-Sánchez, Sonia; Ruiz-Matute, Ana I; Alañón, María Elena; Pérez-Coello, María Soledad; de Julio-Torres, Luis F; Morales, Ramón; Martínez-Castro, Isabel

2010-08-15

The carbohydrate profile of some woods used for aging wines and spirits has been recently studied using a pressurized liquid extraction method, the main differences found being related to cyclitol content. The aim of this study was to perform a detailed study of these compounds in woods of different Quercus species in order to identify two unknown compounds which appeared in the extracts and to verify whether the obtained profile was homogeneous for other Quercus species. Besides the known monosaccharides and five cyclitols previously described, three deoxy-inositols (epi-, vibo- and scyllo-quercitol) were identified. The presence of these eight cyclitols was confirmed in all subgenera and species of Quercus analyzed, allowing a characteristic cyclitol profile. Three deoxy-inositols (quercitols) have been identified in the carbohydrate profile of oak wood. All examined Quercus species displayed a common profile consisting of four inositols and four quercitols, which represent a good dataset for characterization of this genus. Copyright (c) 2010 Society of Chemical Industry.

The dynamic response of housing values to a forst invasive disease: evidence from a sudden oak death infestation

Science.gov (United States)

Kent Kovacs; Thomas P. Holmes; Jeffrey E. Englin; Janice Alexander

2011-01-01

"Sudden Oak Death" (Phytophthora ramorum) is a non-indigenous forest pathogen which causes substantialmortality of coast live oak (Quercus agrifolia) and several other oak tree species on the Pacific Coast of the United States. We estimated the time path of residential property values subject to oak mortality using a...

Effects of fire and browsing on regeneration of blue oak

Science.gov (United States)

James W. Bartolome; Mitchel P. McClaran; Barbara H. Allen-Diaz; Jim Dunne; Lawrence D. Ford; Richard B. Standiford; Neil K. McDougald; Larry C. Forero

2002-01-01

Blue oaks (Quercus douglasii) are not regenerating well over much of California. The roles of fire and browsing in regeneration are probably significant, but poorly understood. We burned two foothill blue oak woodland sites which contained significant numbers of small trees between 40 and 70 cm tall, then compared height growth over 14 years among 48...

Comparison of three sampling methods in the characterization of cork oak stands for management purpose

NARCIS (Netherlands)

Paulo, M.J.; Tomé, M.; Otten, A.; Stein, A.

2005-01-01

The cork oak (Quercus suber L.) is an evergreen oak that has the ability to produce a continuous layer of cork tissue which regenerates after being removed. Cork oak stands can be diverse in structure. Young stands are often regularly spaced, whereas older stands usually show clustering and can be

Photosynthesis and xanthophyll cycle-mediated photoprotection in leaves of Quercus rubra and Q. alba seedlings of different light environments

Science.gov (United States)

Shi-Jean S. Sung; Dianpeng Xu; Paul P. Kormanik; Clanton C. Black

1997-01-01

Two and three years after the outplanting of 1-0 northern red oak (Quercus rubra, NRO) and white oak (Q. alba, WO) nursery stocks, the highest net photosynthetic rates (Amax) were observed from seedlings growing on a clearcut site, followed by those under a pine stand. Both NRO and WO...

Phytophthora ramorum in coast live oak: search for resistance and mechanisms.

Science.gov (United States)

B.A. McPherson; D.L. Wood; S.R. Mori; A. Conrad; P. Bonello

2013-01-01

Despite the presence of Phytophthora ramorum in northern and central California forests since at least 1994, asymptomatic coast live oaks (Quercus agrifolia Née) still remain in heavily infested stands. Coast live oak infection and mortality rates of 5 percent y-1 and 3 percent y-1, respectively, observed in long-term...

Herbivory and the cycling of nitrogen and phosphorus in isolated California oak trees

Science.gov (United States)

David Y. Hollinger

1986-01-01

Nitrogen and phosphorus flow in litterfall and throughfall were studied in two California Quercus species (the evergreen Q.agrifolia and deciduous Q. lobata) before, during, and after an outbreak of the California oak moth, Phryganidia californica. All of the foliage of both oak species was...

The Influence of Epiphytic Lichens on the Nutrient Cycling of a Blue Oak Woodland

Science.gov (United States)

Johannes M. Knops; Thomas H. H. Nash III; William H. Schlesinger

1997-01-01

We evaluated the importance of epiphytic lichens in the nutrient cycling of a blue oak (Quercus douglasii) woodland in California. Each oak tree contained an average of 3.8 kg lichen biomass, totaling 590 kg per ha. For comparison, oak leaf biomass was 958 kg per ha. We compared tree growth, volume and composition of throughfall (rainfall falling...

Risk factors of oak decline and regional mortality patterns in the Ozark Highlands of Arkansas and Missouri

Science.gov (United States)

Martin A. Spetich; Zhaofei Fan; Xiuli Fan; Hong He; Stephen R. Shifley; W. Keith Moser

2011-01-01

Since the late 1970s, oak decline and mortality have plagued Midwestern-upland oak-hickory forests, particularly species in the red oak group (Quercus Section Lobatae) across the Ozark Highlands of Missouri, Arkansas, and Oklahoma (Dwyer and others 1995). Drought is a common inciting factor in oak decline, while advanced tree age is considered a...

Using a down-scaled bioclimate envelope model to determine long-term temporal connectivity of Garry oak (Quercus garryana) habitat in western North America: implications for protected area planning.

Science.gov (United States)

Pellatt, Marlow G; Goring, Simon J; Bodtker, Karin M; Cannon, Alex J

2012-04-01

Under the Canadian Species at Risk Act (SARA), Garry oak (Quercus garryana) ecosystems are listed as "at-risk" and act as an umbrella for over one hundred species that are endangered to some degree. Understanding Garry oak responses to future climate scenarios at scales relevant to protected area managers is essential to effectively manage existing protected area networks and to guide the selection of temporally connected migration corridors, additional protected areas, and to maintain Garry oak populations over the next century. We present Garry oak distribution scenarios using two random forest models calibrated with down-scaled bioclimatic data for British Columbia, Washington, and Oregon based on 1961-1990 climate normals. The suitability models are calibrated using either both precipitation and temperature variables or using only temperature variables. We compare suitability predictions from four General Circulation Models (GCMs) and present CGCM2 model results under two emissions scenarios. For each GCM and emissions scenario we apply the two Garry oak suitability models and use the suitability models to determine the extent and temporal connectivity of climatically suitable Garry oak habitat within protected areas from 2010 to 2099. The suitability models indicate that while 164 km(2) of the total protected area network in the region (47,990 km(2)) contains recorded Garry oak presence, 1635 and 1680 km(2) of climatically suitable Garry oak habitat is currently under some form of protection. Of this suitable protected area, only between 6.6 and 7.3% will be "temporally connected" between 2010 and 2099 based on the CGCM2 model. These results highlight the need for public and private protected area organizations to work cooperatively in the development of corridors to maintain temporal connectivity in climatically suitable areas for the future of Garry oak ecosystems.

Crown condition dynamics of oak in southern Sweden 1988-1999.

Science.gov (United States)

Drobyshev, Igor; Anderson, Stefan; Sonesson, Kerstin

2007-11-01

Crown defoliation of oak (Quercus robur and Q. petraea) was analysed in 808 trees during three forest condition surveys (1988, 1993, and 1999) in the southern Sweden. From 1988 to 1999 crown defoliation increased by more than 20%. Changes in crown defoliation were related to the pH in the upper 20-30 cm of the mineral soils, which was closely connected to other measures of soil fertility (cation exchange capacity, CEC and C/N ratio). Trees growing on soils with a high pH (> or =4.00, in BaCl2 filtrate), high CEC and low C/N ratio had significantly lower crown defoliation than trees growing on more acid soils (pH trees with respect to crown defoliation, indicating that decline in crown condition was not due to an age-related increase in crown transparency. Considering only trees younger than 100 years, a significant interaction was observed between changes in crown defoliation and soil pH. Trees younger than 100 years old growing on more acidic soils had a greater increase in crown transparency than trees on more basic soils between 1988 and 1999. Trees > or =100 years old had significantly higher defoliation on more acidic than on more basic soils, however defoliation dynamics of these trees over 1988-99 was not related to soil acidity. Two biotic agents (insect and fungal leaf infections) evaluated in this study did not prove to be important drivers of defoliation dynamics.

Response of Advance Cherrybark Oak Reproduction to Midstory Removal and Shoot Clipping

Science.gov (United States)

Brian R. Lockhart; John D. Hodges; Emile S. Gardiner

2000-01-01

A Midstory competition control and shoot clipping have been proposed to increase the vigor and height of advance bottomland oak reproduction. Results from a study in east-central Mississippi showed that advance cherrybark oak (Quercus pagoda Raf) released from midstory competition had greater survival than nonreleased seedlings, 64% and 48%,...

Did the late spring frost in 2007 and 2011 affect tree-ring width and earlywood vessel size in Pedunculate oak (Quercus robur) in northern Poland?

Science.gov (United States)

Puchałka, Radosław; Koprowski, Marcin; Przybylak, Julia; Przybylak, Rajmund; Dąbrowski, Henryk P

2016-08-01

Trees are sensitive to extreme weather and environmental conditions. This sensitivity is visible in tree-ring widths and cell structure. In our study, we hypothesized that the sudden frost noted at the beginning of May in both 2007 and 2011 affected cambial activity and, consequently, the number and size of vessels in the tree rings. It was decided to test this hypothesis after damage to leaves was observed. The applied response function model did not show any significant relationships between spring temperature and growth. However, this method uses average values for long periods and sometimes misses the short-term effects. This is why we decided to study each ring separately, comparing them with rings unaffected by the late frost. Our study showed that the short-term effect of sudden frost in late spring did not affect tree rings and selected cell parameters. The most likely reasons for this are (i) cambial activity producing the earlywood vessels before the occurrence of the observed leaf damage, (ii) the forest micro-climate protecting the trees from the harsh frost and (iii) the temperature decline being too short-lived an event to affect the oaks. On the other hand, the visible damage may be occasional and not affect cambium activity and tree vitality at all. We conclude that oak is well-adapted to this phenomenon.

Agrilus auroguttatus exit hole distributions on Quercus agrifolia boles and a sampling method to estimate their density on individual trees

Science.gov (United States)

Laurel J. Haavik; Tom W. Coleman; Mary Louise Flint; Robert C. Venette; Steven J. Seybold

2012-01-01

In recent decades, invasive phloem and wood borers have become important pests in North America. To aid tree sampling and survey efforts for the newly introduced goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), we examined spatial patterns of exit holes on the boles (trunks) of 58 coast live oak, Quercus...

Dendrochronological analysis of white oak growth patterns across a topographic moisture gradient in southern Ohio

Science.gov (United States)

Alexander K. Anning; Darrin L. Rubino; Elaine K. Sutherland; Brian C. McCarthy

2013-01-01

Moisture availability is a key factor that influences white oak (Quercus alba L.) growth and wood production. In unglaciated eastern North America, available soil moisture varies greatly along topographic and edaphic gradients. This study was aimed at determining the effects of soil moisture variability and macroclimate on white oak growth in mixed-oak forests of...

Chloroplast DNA analysis of Tunisian cork oak populations (Quercus suber L.): sequence variations and molecular evolution of the trnL (UAA)-trnF (GAA) region.

Science.gov (United States)

Abdessamad, A; Baraket, G; Sakka, H; Ammari, Y; Ksontini, M; Hannachi, A Salhi

2016-10-24

Sequences of the trnL-trnF spacer and combined trnL-trnF region in chloroplast DNA of cork oak (Quercus suber L.) were analyzed to detect polymorphisms and to elucidate molecular evolution and demographic history. The aligned sequences varied in length and nucleotide composition. The overall ratio of transition/transversion (ti/tv) of 0.724 for the intergenic spacer and 0.258 for the pooled sequences were estimated, and indicated that transversions are more frequent than transitions. The molecular evolution and demographic history of Q. suber were investigated. Neutrality tests (Tajima's D and Fu and Li) ruled out the null hypothesis of a strictly neutral model, and Fu's Fs and Ramos-Onsins and Rozas' R2 confirmed the recent expansion of cork oak trees, validating its persistency in North Africa since the last glaciation during the Quaternary. The observed uni-modal mismatch distribution and the Harpending's raggedness index confirmed the demographic history model for cork oak. A phylogenetic dendrogram showed that the distribution of Q. suber trees occurs independently of geographical origin, the relief of the population site, and the bioclimatic stages. The molecular history and cytoplasmic diversity suggest that in situ and ex situ conservation strategies can be recommended for preserving landscape value and facing predictable future climatic changes.

Bat activity at remnant oak trees in California Central Coast vineyards

Science.gov (United States)

William D. Tietje; Ted Weller; Christopher C. Yim

2015-01-01

During 1990 to 2013, the area planted with wine grapes increased nearly 4.5 times in San Luis Obispo County. Much of this development occurred on open oak savanna with scattered oak (Quercus spp.) trees. Remnant trees are retained in some vineyards, but their value to biodiversity retention has not been quantified. During April to September 2014,...

Suitability of native and ornamental oak species in California for Agrilus auroguttatus

Science.gov (United States)

L.J. Haavik; A.D. Graves; T.W. Coleman; F.L. Flint; R.C. Venette; S.J. Seybold

2014-01-01

Goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), is a new invasive species in southern California, USA. The extent of the host range of this insect is not known, but this knowledge will have a major impact on assessment of the risks that this pest poses to oaks [Quercus spp. (Fagaceae)]. We...

Recent advances in the control of oak wilt in the United States

Science.gov (United States)

Dan A. Wilson

2005-01-01

Oak wilt, caused by Ceratocystis fagacearum (T.W.Bretz) J. Hunt, is probably the most destructive disease of oak trees (Quercus species) in the United States, and is currently causing high morality at epiphytotic proportions in central Texas. The serious potential for damage pro,pted an increase in federal funding within the past...

Comparative Studies Of Oak (Quercus Petraea L. Reservations Within Cluj Forestry

Directory of Open Access Journals (Sweden)

Adrian FUSTOS

2017-05-01

Full Text Available In Romania it is necessary a sustained effort to extend the forest areas through artificial regeneration. The purpose of this study is to show the correlation between the heights and diameters of Quercus petraea trees from seed reserves and their seed production. They were chosen 80 trees situated in four Quercus petraea seed reserves of Cluj County. The trees selected were located at a distance of 30 meters from each other. It has been found that the two measured variables (core diameter and trees height are direct positive correlated, in the sense that increasing the value of a variable and thus leads to an increase in the other. Choosing trees with special qualities have great importance when it comes to transmitting genetic gain new generations. Comprehensive analysis of stationary and vegetation characteristics result in reproductive material with significant values as seeds quality and adaptability.

Isoprene emission potentials from European oak forests derived from canopy flux measurements: an assessment of uncertainties and inter-algorithm variability

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Langford, Ben; Cash, James; Acton, W. Joe F.; Valach, Amy C.; Hewitt, C. Nicholas; Fares, Silvano; Goded, Ignacio; Gruening, Carsten; House, Emily; Kalogridis, Athina-Cerise; Gros, Valérie; Schafers, Richard; Thomas, Rick; Broadmeadow, Mark; Nemitz, Eiko

2017-12-01

� 420 µg m-2 h-1); Castelporziano, Italy (121 ± 15 µg m-2 h-1); Ispra, Italy (7590 ± 1070 µg m-2 h-1); and the Observatoire de Haute Provence, France (7990 ± 1010 µg m-2 h-1). Ecosystem-scale isoprene emission potentials were then extrapolated to the leaf-level and compared to previous leaf-level measurements for Quercus robur and Quercus pubescens, two species thought to account for 50 % of the total European isoprene budget. The literature values agreed closely with emission potentials calculated using the G93 algorithm, which were 85 ± 75 and 78 ± 25 µg g-1 h-1 for Q. robur and Q. pubescens, respectively. By contrast, emission potentials calculated using the G06 algorithm, the same algorithm used in a previous study to derive the European budget, were significantly lower, which we attribute to the influence of past light and temperature conditions. Adopting these new G06 specific emission potentials for Q. robur (55 ± 24 µg g-1 h-1) and Q. pubescens (47 ± 16 µg g-1 h-1) reduced the projected European budget by ˜ 17 %. Our findings demonstrate that calculated isoprene emission potentials vary considerably depending upon the specific approach used in their calculation. Therefore, it is our recommendation that the community now adopt a standardised approach to the way in which micrometeorological flux measurements are corrected and used to derive isoprene, and other biogenic volatile organic compounds, emission potentials.

Metabolite profiling to predict resistance to Phytophthora ramorum in natural populations of coast live oak

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A. Conrad; B. Mcpherson; D. Wood; S. Opiyo; S. Mori; P. Bonello

2013-01-01

Sudden oak death, caused by the invasive oomycete pathogen Phytophthora ramorum, continues to shape the dynamics of coastal populations of oak (Quercus spp.) and tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh) in California and tanoak in southwestern Oregon. Over the...

Field test of foliar-spray herbicides to control mountain laurel in mature mixed-oak forests in western Maryland

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Gary W. Miller; Patrick H. Brose; Jeffrey D. Kochenderfer; James N. Kochenderfer; Kurt W. Gottschalk; John R. Denning

2016-01-01

Successful oak (Quercus spp.) regeneration requires the presence of competitive sources of oak reproduction before parent oaks are harvested. Mountain laurel (Kalmia latifolia) in the understory of many Appalachian forests prevents new oak seedlings from receiving adequate sunlight to survive and grow into competitive size classes. This study examined the efficacy of...

A neighborhood analysis of the consequences of Quercus suber decline for regeneration dynamics in Mediterranean forests.

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Beatriz Ibáñez

Full Text Available In forests, the vulnerable seedling stage is largely influenced by the canopy, which modifies the surrounding environment. Consequently, any alteration in the characteristics of the canopy, such as those promoted by forest dieback, might impact regeneration dynamics. Our work analyzes the interaction between canopy neighbors and seedlings in Mediterranean forests affected by the decline of their dominant species (Quercus suber. Our objective was to understand how the impacts of neighbor trees and shrubs on recruitment could affect future dynamics of these declining forests. Seeds of the three dominant tree species (Quercus suber, Olea europaea and Quercus canariensis were sown in six sites during two consecutive years. Using a spatially-explicit, neighborhood approach we developed models that explained the observed spatial variation in seedling emergence, survival, growth and photochemical efficiency as a function of the size, identity, health, abundance and distribution of adult trees and shrubs in the neighborhood. We found strong neighborhood effects for all the performance estimators, particularly seedling emergence and survival. Tree neighbors positively affected emergence, independently of species identity or health. Alternatively, seedling survival was much lower in neighborhoods dominated by defoliated and dead Q. suber trees than in neighborhoods dominated by healthy trees. For the two oak species, these negative effects were consistent over the three years of the experimental seedlings. These results indicate that ongoing changes in species' relative abundance and canopy trees' health might alter the successional trajectories of Mediterranean oak-forests through neighbor-specific impacts on seedlings. The recruitment failure of dominant late-successional oaks in the gaps opened after Q. suber death would indirectly favor the establishment of other coexisting woody species, such as drought-tolerant shrubs. This could lead current

Densities of Agrilus auroguttatus and Other Borers in California and Arizona Oaks

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Laurel J. Haavik

2014-03-01

Full Text Available We investigated within-tree population density of a new invasive species in southern California, the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae, with respect to host species and the community of other borers present. We measured emergence hole densities of A. auroguttatus and other borers on the lower stem (bole of naïve oaks at 18 sites in southern California and on co-evolved oaks at seven sites in southeastern Arizona. We sampled recently dead oaks in an effort to quantify the community of primary and secondary borers associated with mortality—species that were likely to interact with A. auroguttatus. Red oaks (Section Lobatae produced greater densities of A. auroguttatus than white oaks (Section Quercus. On red oaks, A. auroguttatus significantly outnumbered native borers in California (mean ± SE of 9.6 ± 0.7 versus 4.5 ± 0.6 emergence holes per 0.09 m2 of bark surface, yet this was not the case in Arizona (0.9 ± 0.2 versus 1.1 ± 0.2 emergence holes per 0.09 m2. In California, a species that is taxonomically intermediate between red and white oaks, Quercus chrysolepis (Section Protobalanus, exhibited similar A. auroguttatus emergence densities compared with a co-occurring red oak, Q. kelloggii. As an invasive species in California, A. auroguttatus may affect the community of native borers (mainly Buprestidae and Cerambycidae that feed on the lower boles of oaks, although it remains unclear whether its impact will be positive or negative.

Predicting the economic costs and property value losses attributed to sudden oak death damage in California (2010-2020)

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Kent Kovacs; Tomas Václavík; Robert G. Haight; Arwin Pang; Nik J. Cunniffe; Christopher A. Gilligan; Ross K. Meentemeyer

2011-01-01

Phytophthora ramorum, cause of sudden oak death, is a quarantined, non-native, invasive forest pathogen resulting in substantial mortality in coastal live oak (Quercus agrifolia) and several other related tree species on the Pacific Coast of the United States. We estimate the discounted cost of oak treatment, removal, and...

Nuttall Oak Volume and Weight Tables

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Bryce E. Schlaegel; Regan B. Willson

1983-01-01

Volume and weight tables were constructed from a 62-tree sample of Nuttall oak (Quercus nuttallii Palmer) taken in the Mississippi Delta. The tables present volume, green weight, and dry weight of bole wood, bole wood plus bark, and total tree above a one-foot stump as predicted from the nonlinear model Y = 0Db

Phytophthora quercina infections in elevated CO2 concentrations

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Oszako Tomasz

2016-09-01

Full Text Available In the last decades, a new wave of oak decline has been observed in Poland. The most important pathogenic organisms involved in this phenomenon are probably soil-borne pathogens Phytophthoragenus, especially P. quercina. In this work, we sought to test the influence of elevated CO2 concentration on the susceptibility of oaks (Quercus robur L. to infection by P. quercina. In order to test the susceptibility of oak fine roots to infection, we applied phosphite-based fertiliser Actifos in 0.6% concentration. One-year-old oak seedlings were grown for one year in greenhouse with either an ambient atmosphere (400 ppm CO2 or an elevated (800 ppm concentration of CO2. Oaks grown at the elevated CO2 concentration developed longer shoots as proved by statistically significant differences. However, there was no difference in the development of root systems. The application of Actifos had a positive significant effect on the development of shoots and the surface area of fine roots under the elevated CO2 concentration.

Hyperdiversity of ectomycorrhizal fungus assemblages on oak seedlings in mixed forests in the southern Appalachian Mountains

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John F. Walker; Orson K. Miller; Jonathan L. Horton

2005-01-01

Diversity of ectotrophic mycobionts on outplanted seedlings of two oak species (Quercus rubra and Quercus prinus) was estimated at two sites in mature mixed forests in the southern Appalachian Mountains by sequencing nuclear 5.8S rRNA genes and the flanking internal transcribed spacer regions I and II (ITS). The...

Leaf gas exchange of mature bottomland oak trees

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Rico M. Gazal; Mark E. Kubiske; Kristina F. Connor

2009-01-01

We determined how changes in environmental moisture affected leaf gas exchange in Nuttall (Quercus texana Buckley), overcup (Q. lyrata Walt.), and dominant and codominant swamp chestnut (Q. michauxii Nutt.) oak trees in Mississippi and Louisiana. We used canopy access towers to measure leaf level gas...

Twenty-nine years of development in planted cherrybark oak-sweetgum mixtures: implications for future mixed-species hardwood plantations

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Brian Roy Lockhart; Andrew W. Ezell; John D. Hodges; Wayne K. Clatterbuck

2012-01-01

Results from a long-term planted mixture of cherrybark oak (Quercus pagoda Raf.) and sweetgum (Liquidambar styraciflua L.) showed sweetgum taller in height and larger in diameter than cherrybark oak early in plantation development. By age 17, cherrybark oak was similar in height and diameter with sweetgum and by age 21 was taller...

The Insect Guild of White Oak Acorns: Its Effect on Mast Quality in the Ozark and Ouachita National Forests

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Alex C. Mangini; Roger W. Perry

2004-01-01

Abstract - Hardwood regeneration, especially of oaks, is an essential component of ecosystem management in the Ouachita and Ozark Mountains of Arkansas. In addition, oak mast is an important wildlife food. Several species of insects inhabit and consume acorns. Data on the insect guild inhabiting white oak (Quercus alba L.) acorns...

Modeling the effectiveness of tree planting to mitigate habitat loss in blue oak woodlands

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Richard B. Standiford; Douglas McCreary; William Frost

2002-01-01

Many local conservation policies have attempted to mitigate the loss of oak woodland habitat resulting from conversion to urban or intensive agricultural land uses through tree planting. This paper models the development of blue oak (Quercus douglasii) stand structure attributes over 50 years after planting. The model uses a single tree, distance...

Attraction of ambrosia and bark beetles to coast live oaks infected by Phytophthora ramorum

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Brice A. McPherson; Nadir Erbilgin; David L. Wood; Pavel Svihra; Andrew J. Storer; Richard B. Standiford

2008-01-01

Sudden oak death, caused by Phytophthora ramorum (Werres, de Cock & Man in?t Veld), has killed thousands of oaks (Quercus spp.) in coastal California forests since the mid-1990s. Bark and ambrosia beetles that normally colonize dead or severely weakened trees selectively tunnel into the bleeding cankers that are the first...

Change in oak abundance in the eastern United States from 1980 to 2008

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Songlin Fei; Ningning Kong; Kim C. Steiner; W. Keith Moser; Eric B. Steiner

2011-01-01

Although oaks (Quercus spp.) have historically dominated much of the forest land in eastern North America, a great deal of fragmentary and sometimes anecdotal evidence suggests that they have been yielding dominance in recent decades to other, typically more shade-tolerant species. Using FIA data, our work formally quantifies the change in oak abundance in the eastern...

The dynamic response of housing values to a forest invasive disease: evidence from a sudden oak death infestation

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Kent Kovacs; Thomas P Holmes; Jeffrey E Englin; Janice Alexander

2011-01-01

“Sudden Oak Death” (Phytophthora ramorum) is a non-indigenous forest pathogen which causes substantial mortality of coast live oak (Quercus agrifolia) and several other oak tree species on the Pacific Coast of the United States. We estimated the time path of residential property values subject to oak mortality using a dataset that spans more than two decades—including...

Study of the sap-flow and related quantities of oak trees in field experiments

International Nuclear Information System (INIS)

Kanalas, P.; Olah, V.; Szoelloesi, E.; Meszaros, I.; Ander, I.; Fenyvesi, A.

2009-01-01

Complete text of publication follows. Climatology model calculations for the next decades in the Carpathian Basin predict more frequent occurrence of meteorological extremes and, especially, longer droughts with elevated average temperatures during the growing season. A drift of the transition zone between the wooden steppe and the forest regions is predicted, too, resulting in significant reduction and alteration of the climazonal forest communities in the mountainous regions. The aim of our project is obtaining information on the climatic sensitivity of the tree species in the sessile oak - Austrian oak forest stand of the Sikfoekut Project Long Term Ecological Research (LTER) area (Buekk Mountains, NE Hungary). 'Campaign-like' complex field measurements have been performed in contrasting vegetation seasons of 2007 and 2008. As a function of time, stomatal conductance and intensity of sap-flow and stem diameter of Quercus petraea and Quercus cerris trees were measured simultaneously with photosynthetic photon flux density (PPFD), atmospheric pressure, temperature and relative humidity and vapour pressure deficit (VPD) of air, precipitation and soil moisture. It was found that the two oak species of forest stand exhibit similar daily course of stomatal conductance in rainy periods. However, during drought stomatal conductance of Quercus cerris was higher, and after a transitional decrease around midday it exhibited a second maximum in late afternoon. In dry days after a maximum of stomatal conductance at early morning the stomatal closure of Quercus petraea was permanent which might result in 'carbon starvation' of trees if drought is too long. During rainy periods, sap-flow of both species changed in correlation with VPD. In dry period this correlation weakened especially in case of Quercus petraea but a stronger correlation of sap-flow maximum appeared with the decreasing soil moisture content. Quercus cerris showed smaller stem radial variation, than Quercus

Relationship between field resistance to Phytophthora ramorum and constitutive phenolic chemistry of coast live oak

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A.M. Nagle; B.A. McPherson; D.L. Wood; M. Garbelotto; A.O. Conrad; S. Opiyo; P. Bonello

2012-01-01

Sudden oak death, caused by Phytophthora ramorum, has resulted in high levels of coast live oak (Quercus agrifolia Nee (CLO) mortality. However, some CLO survive in areas with high disease pressure and may thus be resistant. We tested the hypothesis that such field resistant trees contain constitutively higher levels of...

Thematic Mapper Analysis of Blue Oak (Quercus douglasii) in Central California

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Paul A. Lefebvre Jr.; Frank W. Davis; Mark Borchert

1991-01-01

Digital Thematic Mapper (TM) satellite data from September 1986 and December 1985 were analyzed to determine seasonal reflectance properties of blue oak rangeland in the La Panza mountains of San Luis Obispo County. Linear regression analysis was conducted to examine relationships between TM reflectance and oak canopy cover, basal area, and site topographic variables....

Sympatric parallel diversification of major oak clades in the Americas and the origins of Mexican species diversity.

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Hipp, Andrew L; Manos, Paul S; González-Rodríguez, Antonio; Hahn, Marlene; Kaproth, Matthew; McVay, John D; Avalos, Susana Valencia; Cavender-Bares, Jeannine

2018-01-01

Oaks (Quercus, Fagaceae) are the dominant tree genus of North America in species number and biomass, and Mexico is a global center of oak diversity. Understanding the origins of oak diversity is key to understanding biodiversity of northern temperate forests. A phylogenetic study of biogeography, niche evolution and diversification patterns in Quercus was performed using 300 samples, 146 species. Next-generation sequencing data were generated using the restriction-site associated DNA (RAD-seq) method. A time-calibrated maximum likelihood phylogeny was inferred and analyzed with bioclimatic, soils, and leaf habit data to reconstruct the biogeographic and evolutionary history of the American oaks. Our highly resolved phylogeny demonstrates sympatric parallel diversification in climatic niche, leaf habit, and diversification rates. The two major American oak clades arose in what is now the boreal zone and radiated, in parallel, from eastern North America into Mexico and Central America. Oaks adapted rapidly to niche transitions. The Mexican oaks are particularly numerous, not because Mexico is a center of origin, but because of high rates of lineage diversification associated with high rates of evolution along moisture gradients and between the evergreen and deciduous leaf habits. Sympatric parallel diversification in the oaks has shaped the diversity of North American forests. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

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van Meeningen, Ylva; Schurgers, Guy; Rinnan, Riikka; Holst, Thomas

2017-09-01

Light is an important environmental factor controlling biogenic volatile organic compound (BVOC) emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 µmol m-2 s-1), whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds α-pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds α-pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or

Long-term effects of single prescribed fires on hardwood regeneration in oak shelterwood stands

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Patrick H. Brose

2010-01-01

One of the arguments against using prescribed fire to regenerate oak (Quercus spp.) forests is that the improvement in species composition of the hardwood regeneration pool is temporary and multiple burns are necessary to achieve and maintain oak dominance. To explore this concern, I re-inventoried a prescribed fire study conducted in the mid-1990s...

THE EFFECT OF GRAIN ANGLE AND SPECIES ON THERMAL CONDUCTIVITY OF SOME SELECTED WOOD SPECIES

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Rasit Esen

2011-06-01

Full Text Available In this study the thermal conductivity of different wood materials was determined. For this purpose, Scots pine (Pinus sylvestris L., Uludag fir (Abies Bornmülleriana Matff, Oriental beech (Fagus orientalis L, Oak (Quercus robur L., and Chestnut of Anatolia (Castanea sativa Mill. woods were used. In the test, the thermal conductivity of the woods was measured according to procedure of ASTM C 1113-99 standards. The lowest thermal conductivity was obtained in the perpendicular direction of Scots pine samples as 0.156 Kcal/mh°C. The highest thermal conductivity was obtained from perpendicular direction of samples in Oriental beech as 0.331 Kcal/mh°C.

Oak regeneration and overstory density in the Missouri Ozarks

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David R. Larsen; Monte A. Metzger

1997-01-01

Reducing overstory density is a commonly recommended method of increasing the regeneration potential of oak (Quercus) forests. However, recommendations seldom specify the probable increase in density or the size of reproduction associated with a given residual overstory density. This paper presents logistic regression models that describe this...

A multi-century analysis of disturbance dynamics in pine-oak forests of the Missouri Ozark Highlands

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Chad King; Rose-Marie. Muzika

2013-01-01

Using dendrochronology and growth release approaches, we analyzed the disturbance history of shortleaf pine (Pinus echinata Mich.) white oak (Quercus alba L.) forests in the Missouri Ozark Highlands. The objectives of this study were to (1) identify growth release events using living and remnant shortleaf pine and white oak, (2)...

Does the structure of wood contribute to understanding the oaks decline phenomenon?

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Mirela Tulik

2014-04-01

Full Text Available Vascular cambium is a meristematic tissue which produces wood centriphugaly and phloem centripetaly. In the structure of wood and phloem, data concerning developmental processes taking place in the cambium is recorded. The history of the cambium is encoded in the dimensions, numbers and arrangements of the wood and phloem cells. For investigations, the wood is usually preferred because it is durable and such data could remain unchanged for centuries, whereas in the phloem due to distorted processes, it deranges after a few years. In broadleaves, the wood is composed of vessels, tracheids, fibers and parenchyma cells. The process of the wood formation consists of the cambial cell derivatives expansion, lignification of its walls and programmed cell death. Since the seventies of the nineteenth century, the process of declining oaks taking place in Europe on a regular basis has been observed. Oak decline is a complex process that involves interactions of both biotic and abiotic factors leading to increased trees mortality. The main goal of the studies is the examination of the structure of wood in declining oaks (Quercus robur L. in respect to physiological (conductive role of this tissue. It is known that on the level of the wood structure, water transport efficiency depends on the diameter of vessels - the main elements of the hydraulic conductivity system. Any reduction of the vessels lumen causes the reduction of the water transport to the organs of the trees body and, therefore, influences organisms survival rate. Anatomical analyses were carried out on wood samples (comprising all annual rings formed during the 30-40 years life of the analyzed trees collected at breast height from the main stem of healthy, weakened and dead oaks. The anatomical traits of the wood like as the width of the annual increments, the diameter and density of early wood vessels were measured. The results which are described in the paper by Tulik (2014 revealed that

Fragmentation patterns of evergreen oak woodlands in Southwestern Iberia: identifying key spatial indicators.

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Costa, Augusta; Madeira, Manuel; Lima Santos, José; Plieninger, Tobias; Seixas, Júlia

2014-01-15

Mediterranean evergreen oak woodlands (composed of Quercus suber L. and Quercus rotundifolia Lam.) are becoming increasingly fragmented in the human-modified landscapes of Southwestern Portugal and Spain. Previous studies have largely neglected to assess the spatial changes of oak woodlands in relation to their surrounding landscape matrix, and to characterize and quantify woodland boundaries and edges. The present study aims to fill this gap by analyzing fragmentation patterns of oak woodlands over a 50-year period (1958-2007) in three landscapes. Using archived aerial imagery from 1958, 1995 and 2007, for two consecutive periods (1958-1995 and 1995-2007), we calculated a set of landscape metrics to compare woodland fragmentation over time. Our results indicated a continuous woodland fragmentation characterized by their edge dynamics. From 1958 to 2007, the replacement of open farmland by shrubland and by new afforestation areas in the oak woodland landscape surrounding matrix, led to the highest values for edge contrast length trends of 5.0 and 12.3, respectively. Linear discriminant analysis was performed to delineate fragmented woodland structures and identify metric variables that characterize woodland spatial configuration. The edge contrast length with open farmland showed a strong correlation with F1 (correlations ranging between 0.55 and 0.98) and may be used as a proxy for oak woodland mixedness in landscape matrix. The edge dynamics of oak woodlands may result in different patterns of oak recruitment and therefore, its study may be helpful in highlighting future baselines for the sustainable management of oak woodlands. Copyright © 2013 Elsevier Ltd. All rights reserved.

First discovery of Quercus feeding Nepticulidae (Lepidoptera) in Central America.

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Stonis, Jonas R; Diškus, Arūnas; Remeikis, Andrius; Schuster, Jack

2013-11-18

Despite the high taxonomic diversity of oaks in Mexico and Central America, no Quercus feeding Nepticulidae have ever been recorded from the region. Here, we present seven species whose larvae are leaf-miners of Quercus (section Lobatae) in Guatemala. Except Stigmella nigriverticella (Chambers 1875), which was previously known from the United States, all other discovered species are new. We describe and name five new species (Stigmella jaguari Remeikis & Stonis, sp. nov., S. lauta Diškus & Stonis, sp. nov., S. sublauta Remeikis & Stonis, sp. nov., S. aurifasciata Diškus & Stonis, sp. nov. and S. guatemalensis Diškus & Stonis, sp. nov.); the remaining new species is described but left unnamed because of lack of adults (i. e. moths and genitalia are described from developed pupae). All seven treated species are illustrated with photographs of the leaf-mines, adults, and genitalia.

Interspecific gene flow and maintenance of species integrity in oaks

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Oliver Gailing

2014-07-01

Full Text Available Oak species show a wide variation in morphological and physiological characters, and species boundaries between closely related species are often not clear-cut. Still, despite frequent interspecific gene flow, oaks maintain distinct morphological and physiological adaptations. In sympatric stands, spatial distribution of species with different ecological requirements is not random but constrained by soil and other microenvironmental factors. Pre-zygotic isolation (e.g. cross incompatibilities, asynchrony in flowering, pollen competition and post-zygotic isolation (divergent selection contribute to the maintenance of species integrity in sympatric oak stands. The antagonistic effects of interspecific gene flow and divergent selection are reflected in the low genetic differentiation between hybridizing oak species at most genomic regions interspersed by regions with signatures of divergent selection (outlier regions. In the near future, the availability of high-density genetic linkage maps anchored to scaffolds of a sequenced Q. robur genome will allow to characterize the underlying genes in these outlier regions and their putative role in reproductive isolation between species. Reciprocal transplant experiments of seedlings between parental environments can be used to characterize selection on outlier genes. High transferability of gene-based markers will enable comparative outlier screens in different oak species.

Effect of temperature on postillumination isoprene emission in oak and poplar.

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Li, Ziru; Ratliff, Ellen A; Sharkey, Thomas D

2011-02-01

Isoprene emission from broadleaf trees is highly temperature dependent, accounts for much of the hydrocarbon emission from plants, and has a profound effect on atmospheric chemistry. We studied the temperature response of postillumination isoprene emission in oak (Quercus robur) and poplar (Populus deltoides) leaves in order to understand the regulation of isoprene emission. Upon darkening a leaf, isoprene emission fell nearly to zero but then increased for several minutes before falling back to nearly zero. Time of appearance of this burst of isoprene was highly temperature dependent, occurring sooner at higher temperatures. We hypothesize that this burst represents an intermediate pool of metabolites, probably early metabolites in the methylerythritol 4-phosphate pathway, accumulated upstream of dimethylallyl diphosphate (DMADP). The amount of this early metabolite(s) averaged 2.9 times the amount of plastidic DMADP. DMADP increased with temperature up to 35°C before starting to decrease; in contrast, the isoprene synthase rate constant increased up to 40°C, the highest temperature at which it could be assessed. During a rapid temperature switch from 30°C to 40°C, isoprene emission increased transiently. It was found that an increase in isoprene synthase activity is primarily responsible for this transient increase in emission levels, while DMADP level stayed constant during the switch. One hour after switching to 40°C, the amount of DMADP fell but the rate constant for isoprene synthase remained constant, indicating that the high temperature falloff in isoprene emission results from a reduction in the supply of DMADP rather than from changes in isoprene synthase activity.

Powdery Mildew Decreases the Radial Growth of Oak Trees with Cumulative and Delayed Effects over Years.

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Didier Bert

Full Text Available Quercus robur and Q. petraea are major European forest tree species. They have been affected by powdery mildew caused by Erysiphe alphitoides for more than a century. This fungus is a biotrophic foliar pathogen that diverts photosynthetate from the plant for its own nutrition. We used a dendrochronological approach to investigate the effects of different levels of infection severity on the radial growth of young oak trees. Oak infection was monitored at individual tree level, at two sites in southwestern France, over a five-year period (2001-2005. Mean infection severity was almost 75% (infected leaf area at the end of the 2001 growing season, at both sites, but only about 40% in 2002, and 8%, 5% and 2% in 2003, 2004 and 2005, respectively. Infection levels varied considerably between trees and were positively related between 2001 and 2002. Increment cores were taken from each tree to assess annual ring widths and increases in basal area. Annual radial growth was standardised to take the effect of tree size into account. Annual standardised radial growth was significantly and negatively correlated with infection severity in the same year, for both 2001 and 2002, and at both sites. The decrease in growth reached 70-90% for highly infected trees. The earlywood width was poorly correlated with infection severity, but the proportion of latewood in tree rings was lower in highly infected trees (60% than in less heavily infected trees (85%. Infection in 2001 and 2002 was found to have a cumulative effect on radial growth in these years, together with a delayed effect detectable in 2003. Thus, even non-lethal pathogens like powdery mildew can have a significant impact on tree functioning. This impact should be taken into account in growth and yield models, to improve predictions of forest net primary production.

Vegetation Change in Blue Oak Woodlands in California

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Barbara A. Holzman; Barbara H. Allen-Diaz

1991-01-01

A preliminary report of a statewide project investigating vegetation change in blue oak (Quercus douglasii) woodlands in California is presented. Vegetation plots taken in the 1930s, as part of a statewide vegetation mapping project, were relocated and surveyed. Species composition, cover and tree stand structure data from the earlier study were...

Comparing single-tree selection, group selection, and clearcutting for regenerating oaks and pines in the Missouri Ozarks

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Randy G. Jensen; John M. Kabrick

2008-01-01

In the Missouri Ozarks, there is considerable concern about the effectiveness of the uneven-aged methods of single-tree selection and group selection for oak (Quercus L.) and shortleaf pine (Pinus echinata Mill.) regeneration. We compared the changes in reproduction density of oaks and pine following harvesting by single-tree...

Use of damage surveys and field inventories to evaluate oak and sugar maple health in the northern United States

Science.gov (United States)

Randall S Morin; Christopher W. Woodall; Jim Steinman; Charles H. Perry

2009-01-01

Oak species (Quercus spp.) and sugar maple (Acer saccharum) are substantial components of the forest ecosystems in the 24-state region spanning the northern U.S. During recent decades, both damage surveys and forest inventories have documented declines of sugar maple and oak health. In order to more fully assess the status of oak and sugar maple health, we examined...

Monitoring Genetic Stability in Quercus serrata Thunb. Somatic Embryogenesis Using RAPD Markers

OpenAIRE

Ramesh C., Thakur; Susumu, Goto; Katsuaki, Ishii; S. Mohan, Jain; Forestry and Forest Products Research Institute; Fukuoka Prefecture Forest Research and Extension Center; Forestry and Forest Products Research Institute; University of Helsinki

1999-01-01

Genetic stability of propagules regenerated via somatic embryogenesis is of paramount importance for its application to clonal forestry. Random amplified polymorphic DNA (RAPD) markers were used to determine the genetic stability in somatic embryogenesis of Quercus serrata Thunb. (Japanese white oak). Forty samples from an embryogenic line, consisting of regenerated plantlets, somatic embryos, and embryogenic calli, were examined using 54 decanucleotide primers. A total of 6520 clear reproduc...

Assessment of Virulence of Raffaelea quercus-mongolicae and Raffaelea spp. Isolates by Artificial Inoculation of Quercus mongolica Logs

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Su-Yeon Son

2014-12-01

Full Text Available The objective of this study was to evaluate the virulence of geographically different isolates of oak wilt pathogen, Raffaelea quercus-mongolicae and other Raffaelea species. In this study, mature trees of Quercus mongolica were inoculated with the various isolates of Raffaelea spp. and their virulence was evaluated by measuring the extent of sapwood discoloration resulting from the inoculation. The average length of discolored sapwood in a lateral direction was longest in the trees inoculated with the isolates from Korea (8.69 cm followed by R. quercivora (7.51 cm and the other Raffaelea spp. (3.35 cm. The lateral length of discolored sapwood caused by the inoculation with Korean strains varied from 4.71 to 14.90 cm indicating their differences in virulence. The area of discolored sapwood caused by the inoculation with Raffaelea spp. varied from 1.57 to 8.42 cm2 indicating their differences in virulence. Based on the length and area of the discolored sapwoods, isolated YY and wj43 appeared to have the highest virulence among all the Raffaelea isolates tested. Each of the two isolates was obtained from Gangwon Province and Jeonbuk Province, respectively.

Field performance of Quercus bicolor established as repeatedly air-root-pruned container and bareroot planting stock

Science.gov (United States)

J.W." Jerry" Van Sambeek; Larry D. Godsey; William D. Walter; Harold E. Garrett; John P. Dwyer

2016-01-01

Benefits of repeated air-root-pruning of seedlings when stepping up to progressively larger containers include excellent lateral root distribution immediately below the root collar and an exceptionally fibrous root ball. To evaluate long-term field performance of repeatedly air-root-pruned container stock, three plantings of swamp white oak (Quercus bicolor...

A time and a place for everything: phylogenetic history and geography as joint predictors of oak plastome phylogeny

Science.gov (United States)

Kasey K. Pham; Andrew L. Hipp; Paul S. Manos; Richard C. Cronn

2017-01-01

Owing to high rates of introgressive hybridization, the plastid genome is poorly suited to fine-scale DNA barcoding and phylogenetic studies of the oak genus (Quercus, Fagaceae). At the tips of the oak plastome phylogeny, recent gene migration and reticulation generally cause topology to reflect geographic structure, while deeper branches reflect...

Impact of straw and rock-fragment mulches on soil moisture and early growth of holm oaks in a semiarid area

Science.gov (United States)

M. N. Jimenez; J. R. Pinto; M. A. Ripoll; A. Sanchez-Miranda; F. B. Navarro

2017-01-01

Planted seedlings and saplings usually exhibit low survival and growth rates under dry Mediterranean environments, especially late-successional species such as Quercus. In this work, we studied the effects of straw and rock fragment mulches on the establishment conditions of holm oak (Quercus ilex L. subsp. ballota (Def.) Samp.) in SE Spain. Soil moisture was...

The Response of Basal Area Increment in Old Sprout-origin Sessile Oak (Quercus petraea (Matt. Liebl. Trees During Their Conversion to a Coppice-with-standards

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Zdeněk Adamec

2014-01-01

Full Text Available This paper addresses the response of adult sprout-origin sessile oaks (Quercus petraea (Matt. Liebl. to a strong release. Our research plot was established at the Training Forest Enterprise of Mendel University in Brno (Czech Republic at the turn of 2008/2009. The plot is situated on a plateau with mesotrofic soil in a beech-oak forest vegetation zone at an altitude of 410 m above sea level. Tree responses were monitored using precise girth measurements. During the first year after the release, the basal area increment showed a positive correlation with only the tree diameter. During the second and third year, the basal area increment was also correlated with the release intensity. During the third year, the basal area increment was explained by the tree diameter, the crown shape, and the release intensity as well as individual types of epicormic shoot occurrence. The occurrence of epicormic shoots in the lower part of the trunks and umbel-shaped crowns increased the basal area increment. In the first, second and third year after thinning, the model explained 11.79%, 11.25% and 28.99%, respectively, of the basal area increment variability. Adult trees of sprout origin responded to a strong release very early (within two years after felling.

Assessment of oak wilt threat to habitat of the golden-cheeked warbler, an endangered species, in central Texas

Science.gov (United States)

David N. Appel; Kim S. Camilli

2010-01-01

A major epidemic of oak wilt, caused by Ceratocystis fagacearum (Bretz) Hunt, has been killing trees in Central Texas for at least 40 years. This has created large and expanding canopy gaps in the vast, homogenous live oak woodlands (Quercus fusiformis Small) in the Edwards Plateau region of Texas. The changes in stand...

Penicillium cecidicola, a new species on cynipid insect galls on Quercus pacifica in the western United States

DEFF Research Database (Denmark)

Seifert, K.A.; Hoekstra, E.H.; Frisvad, Jens Christian

2004-01-01

A synnematous species of Penicillium subgenus Biverticillium was found inside emergence tunnels from insect galls (Cynipidae, Hymenoptera, the so-called gall wasps) on scrub oaks (Quercus pacifica Nixon & C.H. Muller) collected in the western United States. The fungus produces synnemata with white...... isolates exposed to light after 10 days. The fungus produces the extrolite apiculide A and a series of unidentified extrolites also produced by P. panamense. The oak gall species is described here as Penicillium cecidicola and compared with similar species. An ITS phylogeny suggests that P. cecidicola...

A stable-isotope tree-ring timescale of the Late Glacial/Holocene boundary

International Nuclear Information System (INIS)

Becker, Bernd; Kromer, Bernd; Trimborn, Peter

1991-01-01

Late Glacial and Holocene tree-ring chronologies, like deep-sea sediments or polar ice cores, contain information about past environments. Changes in tree-ring growth rates can be related to past climate anomalies and changes in the isotope composition of tree-ring cellulose reflect changes in the composition of the atmosphere and the hydrosphere. We have established a 9,928-year absolutely dated dendrochronological record of Holocene oak (Quercus robur, Quercus petraea)-and a 1,604-year floating Late Glacial and Early Holocene chronology of pine (Pinus sylvestris) from subfossil tree remnants deposited in alluvial terraces of south central European rivers. The pine sequence provides records of dendro-dated 14 C, 13 C and 2 H patterns for the late Younger Dryas and the entire Preboreal (10,100-9,000 yr BP). Through the use of dendrochronology, radiocarbon age calibration and stable isotope analysis, we suggest that the Late Glacial/Holocene transition may be identified and dated by 13 C and 2 H tree-ring chronologies. (author)

Direct Seeding Scarlet Oak in the North Carolina Mountains

Science.gov (United States)

Earl R. Sluder

1965-01-01

Seedling establishment rates varied from 0 to 50 percent in a direct seeding study with scarlet oak (Quercus coccinea Muenchh.) on the Bent Creek Experimental Forest near Asheville, North Carolina. Acorns planted 2 inches deep in the spring with screen protection produced the most seedlings; those surface sown without screens in the spring or fall...

Phenological responses of juvenile pecan and white oak on an upland site

Science.gov (United States)

Pecan (Carya illinoiensis) and white oak (Quercus alba) produce multiple products and wildlife values, but their phenological responses to N fertilization have not been well characterized in an mixed species agroforestry practice. We compared tree height at planting and for six consecutive growing ...

TESTING BAYESIAN ALGORITHMS TO DETECT GENETIC STRUCTURE IN TWO CLOSELY RELATED OAK TAXA

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Cristian Mihai Enescu

2013-12-01

Full Text Available The aim of this study was to test the Bayesian algorithm implemented in the software STRUCTURE in order to detect the number of clusters, by using microsatellite data from four oak species. Several assignment models, with or without a priori grouping of individuals to species, were proposed. Better results were obtained by using the sampling location information and when only two taxa were analyzed. Particularly, pedunculate oak and sessile oak formed distinct clusters whatever the assignment model we use. By contrast, no separation between the two oaks from series Lanuginosae was observed. This can be explained, on one hand, by the small sampling size for Italian oak, or by the genetic similarities of the two pubescent oaks, namely Quercus pubescens and Q. virgiliana, on the other hand. Our findings support the hypothesis according which Italian oak is an intraspecific taxonomic unit of pubescent oak.

Isoprene emission potentials from European oak forests derived from canopy flux measurements: an assessment of uncertainties and inter-algorithm variability

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B. Langford

2017-12-01

��µg m−2 h−1; Bosco Fontana, Italy (1610 ± 420 µg m−2 h−1; Castelporziano, Italy (121 ± 15 µg m−2 h−1; Ispra, Italy (7590 ± 1070 µg m−2 h−1; and the Observatoire de Haute Provence, France (7990 ± 1010 µg m−2 h−1. Ecosystem-scale isoprene emission potentials were then extrapolated to the leaf-level and compared to previous leaf-level measurements for Quercus robur and Quercus pubescens, two species thought to account for 50 % of the total European isoprene budget. The literature values agreed closely with emission potentials calculated using the G93 algorithm, which were 85 ± 75 and 78 ± 25 µg g−1 h−1 for Q. robur and Q. pubescens, respectively. By contrast, emission potentials calculated using the G06 algorithm, the same algorithm used in a previous study to derive the European budget, were significantly lower, which we attribute to the influence of past light and temperature conditions. Adopting these new G06 specific emission potentials for Q. robur (55 ± 24 µg g−1 h−1 and Q. pubescens (47 ± 16 µg g−1 h−1 reduced the projected European budget by ∼ 17 %. Our findings demonstrate that calculated isoprene emission potentials vary considerably depending upon the specific approach used in their calculation. Therefore, it is our recommendation that the community now adopt a standardised approach to the way in which micrometeorological flux measurements are corrected and used to derive isoprene, and other biogenic volatile organic compounds, emission potentials.

Soil respiration and rates of soil carbon turnover differ among six common European tree species

DEFF Research Database (Denmark)

Vesterdal, Lars; Elberling, Bo; Christiansen, Jesper Riis

2012-01-01

replicated at six sites in Denmark. The studied tree species were the broadleaves beech (Fagus sylvatica L.), pedunculate oak (Quercus robur L.), lime (Tilia cordata L.), sycamore maple (Acer pseudoplatanus L.) and ash (Fraxinus excelsior L.) and the conifer Norway spruce (Picea abies (L.) Karst.). Rates....... Soil respiration differed significantly among several species and increased in the order beechmaple... moisture. Carbon turnover rates based on the ratio between R h and C stock were significantly higher in ash than in all other species except maple, and maple also had higher C turnover than spruce. A similar influence of tree species on C turnover was indicated by the litterfall C to forest floor C ratio...

Elevated CO2 compensates for water stress in northern red oak

Science.gov (United States)

Patricia T. Tomlinson; Paul D. Anderson

1996-01-01

Global climate change models predict decreased rainfall in association with elevated CO2 in the western Lakes States region. Currently, the western edge of northern red oak (Quercus rubra L.) distribution coincides with the most xeric conditions of its ecological range. Decreased rainfall and water availability could alter...

Disking and mid- and understory removal following an above-average acorn crop in three mature oak forests in southern Indiana

Science.gov (United States)

Ronald A. Rathfon; Nathanael I. Lichti; Robert K. Swihart

2008-01-01

We disked using small-scale equipment in the understory of three mature upland oak (Quercus) forests in southern Indiana immediately following acorn dispersal in an aboveaverage seed crop year as a means of improving oak seedling establishment. Three different mid- and understory removal treatments were also applied to create favorable light...

Air pollution effects on Quercus Ilex plants

International Nuclear Information System (INIS)

Pavone, P.; Salmeri, C.; Spampinato, G.; Fallico, R.; Ferrante, M.

1996-01-01

To test air pollution effects on natural forest vegetation, the soil chemistry and the floristic composition of two Quercus ilex L. woods in the Hyblean region (S-E Sicily), unequally exposed to air pollutants are compared. Acidification phenomena are investigated by the soil chemical changes between the trunk base areas, affected by stem flow water, and the surrounding soil, only influenced by canopy drip. Soil chemical changes, floristic poorness and direct damage to the Q. ilex leaves are only detected in the Climiti Mountains holm-oak woods, located near the Siracusa petrochemical complex, while they do not appear at Cava d'Ispica, sited far from any industry and seldom exposed to winds carrying pollutants

Whole-tree silvic identifications and the microsatellite genetic structure of a red oak species complex in an Indiana old-growth forest

Science.gov (United States)

Preston R. Aldrich; George R. Parker; Charles H. Michler; Jeanne Romero-Severson

2003-01-01

The red oaks (Quercus section Lobatae) include important timber species, but we know little about their gene pools. Red oak species can be difficult to identify, possibly because of extensive interspecific hybridization, although most evidence of this is morphological. We used 15 microsatellite loci to examine the genetic...

Warm-cold colonization: response of oaks to uplift of the Himalaya-Hengduan Mountains.

Science.gov (United States)

Meng, Hong-Hu; Su, Tao; Gao, Xiao-Yang; Li, Jie; Jiang, Xiao-Long; Sun, Hang; Zhou, Zhe-Kun

2017-06-01

Clarifying the relationship between distribution patterns of organisms and geological events is critical to understanding the impact of environmental changes on organismal evolution. Quercus sect. Heterobalanus is now distributed across the Himalaya-Hengduan Mountains (HHM) and warm lowland in East China, yet how the distribution patterns of this group changed in response to the HHM uplift remains largely unknown. This study examines the effect of tectonic events in the HHM region on the oaks, providing a biological perspective on the geological history of this region. Fifty-six populations of Quercus sect. Heterobalanus were genotyped using four chloroplast DNA regions and nine nuclear simple sequence repeat loci to assess population structure and diversity, supplemented by molecular dating and ancestral area reconstructions. The underlying demographic dynamics were compared using ecological niche models of the species distributions during the last glacial maximum and the present. These analyses illustrate that Quercus sect. Heterobalanus diversified as the HHM uplifted and climatic cooling during the mid-Miocene, colonizing the cold habitats from warm broadleaf mixed forests. Lineages in cold highlands and warm lowlands have diverged as a consequence of local adaptation to diverging climates since the late Miocene. Our results suggest that continuous uplift of the HHM in the late Miocene to early Pliocene accompanied by simultaneous cooling triggered the differentiation of oaks. The biogeography of Quercus sect. Heterobalanus illuminates the geological events responsible for the modern-day HHM. © 2017 John Wiley & Sons Ltd.

Role of six European tree species and land-use legacy for nitrogen and water budgets in forests

DEFF Research Database (Denmark)

Riis Christiansen, Jesper; Vesterdal, Lars; Callesen, Ingeborg

2010-01-01

-year-old common garden design with stands of common ash (Fraxinus excelsior), European beech (Fagus sylvatica L.), pedunculate oak (Quercus robur), small-leaved lime (Tilia cordata Mill.), sycamore maple (Acer pseudoplatanus) and Norway spruce (Picea abies [L.] Karst.) replicated at two sites...... in Denmark, Mattrup and Vallø during 2 years. Mean annual percolation below the root zone (mm yr−1±SE, n=4) ranked in the following order: maple (351±38)>lime (284±32), oak (271±25), beech (257±30), ash (307±69)≫ spruce (75±24). There were few significant tree species effects on N fluxes. However, the annual...... mean N throughfall flux (kg N ha−1 yr−1±SE, n=4) for spruce (28±2) was significantly larger than for maple (12±1), beech (11±1) and oak (9±1) stands but not different from that of lime (15±3). Ash had a low mean annual inorganic N throughfall deposition of 9.1 kg ha−1, but was only present at Mattrup...

Preliminary work in developing sawbolt grading systems for white oak

Science.gov (United States)

Everette D. Rast; Everette D. Rast

1971-01-01

This paper is principally a description of one technique used in the development of white oak (Quercus alba L.) sawbolt grades--not a final sawbolt grading system for the species over its range. This technique can be used by anyone in developing other bolt-grade specifications or in refining the system presented in this paper.

Establishment of northern red oak genetic tests with nursery-graded seedlings

Science.gov (United States)

S. A. Lay; M. A. Remaley; S. E. Schlarbaum; P. P. Kormanik; T. Tibbs; R. A. Cox; T. LaFarge; A. M. Saxton

1997-01-01

Artificial regeneration of northern red oak (Quercus rubra L.) has had variable success over time. Current nursery practices generally involve the growth of seedlings to a standardized height and form with little regard to seed source, seedling quality, or subsequent field performance. Additionally, there is not an accepted culling criteria for...

Effects of Cardinal Direction on Distribution and Populational Dynamism of Oak Leaf Roller (Tortrix viridana L. on Quercus infectoria Oliv. and Q. libani Lindl.

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mohammadreza zargaran

2018-01-01

Full Text Available Introduction Various pests attack oak trees and in most cases heavily damage them. The European oak leaf roller is one of the important oak pests in some provinces of the Zagros, and it is an important pest of oak forests in some European and North African countries, as well as in Iraq and other regions of Iran. In Iran, it is scattered in the Zagros oak forests, especially in Kohkiluyeh and Boyer Ahmad, Lorestan, Chahar Mahal and Bakhtiari, Fars, and West Azarbaijan Provinces. Repeated removal of oak leaves, particularly by herbivores such as T. viridana in spring, reduces stored photosynthates in trees leading to their decreased diametrical growth. Materials and Methods The Ghabre-Hossein region (Piranshahr was selected as the field operations region because it is one of the most important infestation centers of the European oak leaf roller in the oak forests of West-Azerbaijan. The research was carried out in two consecutive years. Samples of larval instars were taken in early May. Since the sample plot in sampling methods can be points or lines (transects, the four cardinal directions were selected in this study and transects at 100 m intervals were located in each direction.To reduce sampling error, Aleppo (Quercus infectoria and Lebanon (Q. libani oak trees were selected for measurements that were similar in appearance and almost uniform with crowns or trunks aligned along the transects. In each studied tree, four suitable branches were selected (one in each cardinal direction, and the number of larvae from the tip of each branch to a length of 50 cm inwards was counted and recorded in forms prepared beforehand. Considering studies that were carried out regarding the biology of the pest, the larvae were counted in mid-May when all larvae were in their last (fifth instar. In all, 30 Aleppo and 30 Lebanon oak trees were selected in each cardinal direction, and four branches in each direction of these trees were measured. The survey method

The influence of cultural treatments of the long-term survival and growth of planted Quercus rubra

Science.gov (United States)

James J. Zaczek; Kim C. Steiner

2011-01-01

A northern red oak (Quercus rubra L.) plantation testing 20 nursery stock and planting methods was used to evaluate treatments 3, 6, 10, and 17 years after planting. Survival over all treatments was 92 percent at age 3 and declined to 74 percent, 56 percent, and 39 percent at ages 6, 10, and 17, respectively. At age 17, survival was highest for...

Reduced translocation of current photosynthate precedes changes in gas exchange for Quercus rubra seedlings under flooding stress.

Science.gov (United States)

Sloan, Joshua L; Islam, M Anisul; Jacobs, Douglass F

2016-01-01

Northern red oak (Quercus rubra L.) seedlings are frequently planted on suboptimal sites in their native range in North America, subjecting them to environmental stresses, such as flooding, for which they may not be well adapted. Members of the genus Quercus exhibit a wide range of responses to flooding, and responses of northern red oak to flooding remain inadequately described. To better understand the physiological effects of root system inundation in post-transplant northern red oak seedlings and the effects of flooding on endogenous patterns of resource allocation within the plant, we observed the effects of short-term flooding initiated at the linear shoot growth stage on net photosynthetic rates, dark respiration, chlorophyll fluorescence (Fv/Fm) and translocation of (13)C-labeled current photosynthate. Downward translocation of current photosynthate declined after 4 days of flooding and was the first measured physiological response to flooding; net photosynthetic rates decreased and dark respiration rates increased after 7 days of flooding. Short-term flooding did not affect maximal potential efficiency of photosystem II (Fv/Fm). The finding that decreased downward translocation of (13)C-labeled current photosynthate preceded reduced net photosynthesis and increased dark respiration during flooding suggests the occurrence of sink-limited photosynthesis under these conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Is deciduousness a key to climate resilience among iconic California savanna oak species? Relating phenological habits to seasonal indicators of tree physiological and water stress across field, hyperspectral, drone (UAS)-based multispectral and thermal image data

Science.gov (United States)

Mayes, M. T.; Caylor, K. K.; Ehlmann, B. L.; Greenberger, R. N.; Estes, L. D.

2017-12-01

In California (CA) savannas, oak trees (genus Quercus) play keystone roles in water and nutrient cycling, support biodiversity and many land-use activities. Declines in oak basal area of up to 25% from the 1930s-2000s, which have occurred alongside climate trends such as increasing variability of rainfall and prevalence of hotter droughts, threaten the services and ecological functions these trees provide. It is particularly unclear how climate relates to productivity and stress across oak species. Past work has found that seedling recruitment has varied inversely with "deciduousness." That is, evergreen oaks (e.g. Quercus agrifola. Coast Live Oak) are reproducing more successfully than drought-deciduous (e.g. Quercus douglassi, Blue Oak), which in turn are more successful than fully deciduous species (e.g. Quercus lobata, Valley Oak). However, there is poor understanding of how these ecological trends by species, corresponding with phenological habit, relate to physiological and ecohydrological processes such as carbon assimilation, water or nutrient use efficiency in mature tree stands. This limits predictive capability for which species will be most resilient to harsher future growing conditions, and, how to monitor stress and productivity in long-lived mature oak communities across landscapes via tools including remotely sensed data. This project explores how ecophysiological variables (e.g. stomatal conductance) relate to phenological habits across three oak species (Coast Live, Blue and Valley) over a seasonal dry-down period in Santa Barbara County, CA. Our goal is to probe if deciduousness is a key to resilience in productivity and water stress across iconic oak species. We test relationships between leaf and canopy-level field data, and indicators from multiple new sources of remotely sensed data, including ground hyperspectral, drone (UAS)-based multi-spectral and thermal image data, as means of monitoring tree physiological and water stress from scales

Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

Directory of Open Access Journals (Sweden)

Y. van Meeningen

2017-09-01

Full Text Available Light is an important environmental factor controlling biogenic volatile organic compound (BVOC emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur, European beech (Fagus sylvatica and two provenances of Norway spruce (Picea abies in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 µmol m−2 s−1, whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds α-pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds α-pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the

Modeling effects of hydrological changes on the carbon and nitrogen balance of oak in floodplains.

Science.gov (United States)

Pietsch, Stephan A; Hasenauer, Hubert; Kucera, Jiŕi; Cermák, Jan

2003-08-01

We extended the applicability of the ecosystem model BIOME-BGC to floodplain ecosystems to study effects of hydrological changes on Quercus robur L. stands. The extended model assesses floodplain peculiarities, i.e., seasonal flooding and water infiltration from the groundwater table. Our interest was the tradeoff between (a). maintaining regional applicability with respect to available model input information, (b). incorporating the necessary mechanistic detail and (c). keeping the computational effort at an acceptable level. An evaluation based on observed transpiration, timber volume, soil carbon and soil nitrogen content showed that the extended model produced unbiased results. We also investigated the impact of hydrological changes on our oak stands as a result of the completion of an artificial canal network in 1971, which has stopped regular springtime flooding. A comparison of the 11 years before versus the 11 years after 1971 demonstrated that the hydrological changes affected mainly the annual variation across years in leaf area index (LAI) and soil carbon and nitrogen sequestration, leading to stagnation of carbon and nitrogen stocks, but to an increase in the variance across years. However, carbon sequestration to timber was unaffected and exhibited no significant change in cross-year variation. Finally, we investigated how drawdown of the water table, a general problem in the region, affects modeled ecosystem behavior. We found a further amplification of cross-year LAI fluctuations, but the variance in soil carbon and nitrogen stocks decreased. Volume increment was unaffected, suggesting a stabilization of the ecosystem two decades after implementation of water management measures.

Long-term above-ground biomass production in a red oak-pecan agroforestry system

Science.gov (United States)

Agroforestry systems have widely been recognized for their potential to foster long-term carbon sequestration in woody perennials. This study aims to determine the above-ground biomass in a 16-year-old red oak (Quercus rubra) - pecan (Carya illinoinensis) silvopastoral planting (141 and 53 trees ha-...

The response of saprotrophic beetles to coast live oaks infected with Phytophthora ramorum

Science.gov (United States)

Brice A. McPherson; Nadir Ebilgin; David L. Wood; Pavel Svihra; Andrew J. Storer; Richard B. Standiford

2006-01-01

Saprotro phic ambrosia and bark beetles (Coleoptera: Scolytidae) tunnel into the bark overlying cankers caused by Phytophthora ramorum in coast live oaks, Quercus agrifolia. These insects are characteristically reported to colonize freshly dead or moribund trees (Furniss and Carolin, 1977). However, the initial attacks by these...

Phenological responses of juvenile pecan and white oak on an upland site

Science.gov (United States)

D. M. Burner; D. K. Brauer; J. L. Snider; C. A. Harrington; P. A. Moore

2014-01-01

Pecan (Carya illinoiensis) and white oak (Quercus alba) produce multiple products and wildlife values, but their phenological responses to N fertilization have not been well characterized. We compared tree growth at planting and for six consecutive growing seasons during establishment (2003–2008, Test 1), and determined if...

Root desiccation and drought stress responses of bareroot Quercus rubra seedlings treated with a hydrophilic polymer root dip

Science.gov (United States)

Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese

2009-01-01

Root hydrogel, a hydrophilic polymer, has been used to improve transplanting success of bareroot conifer seedlings through effects on water holding capacity. We examined mechanisms by which Terra-sorb Fine Hydrogel reduces damage that occurs when roots of 1-year old, dormant northern red oak (Quercus rubra L.) were subjected to shortterm (1, 3, and 5...

Container volume and subirrigation schedule influence Quercus variabilis seedling growth and nutrient status in the nursery and field

Science.gov (United States)

Qiaoyu Sun; R. Kasten Dumroese; Yong Liu

2018-01-01

Container volume and irrigation management affect seedling growth in the nursery and field. We evaluated the effects of container volumes (D40, 656 ml; D60, 983 ml) and subirrigation schedules (85%, 75%, 65%, and 55% of 100% total substrate moisture content, TSMC) on seedling growth in a greenhouse and outplanting performance of Chinese cork oak (Quercus variabilis...

Spatial modeling and inventories for prioritizing investment into oak-hickory restoration

Science.gov (United States)

Louis R. Iverson; Matthew P. Peters; Jarel L. Bartig; Joanne Rebbeck; Todd F. Hutchinson; Stephen N. Matthews; Susan Stout

2018-01-01

Oak (Quercus spp.) and hickory (Carya spp.) forests in the eastern United States provide a host of ecosystem services as their mast are prized by wildlife, the timber is a valued commodity, and they are generally more tolerant of extreme weather events under a changing climate. They are, however, undergoing a severe decline in...

Planting northern red oak: a comparison of stock types

Science.gov (United States)

J.J. Zaczek; K.C. Steiner; T.W. Bowersox

1991-01-01

Height and survival values of northern red oak (Quercus rubra L.) were compared three years after outplanting as functions of: stock types (direct-seeded, 1-0, 2-0, 1-1, 2-1, and 2-year-old seedlings grown in 7.9-liter pots), presence or absence of undercutting in the nursery, and presence or absence of top-clipping when field planting. In all, 33 or...

Potential improvement of Lymantria dispar L. management by quercetin

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Perić-Mataruga Vesna

2014-01-01

Full Text Available Lymantria dispar, a polyphagous insect pest, copes with a wide variety of host-specific allelochemicals. Glutathione S-transferases (GST are important for catalyzing detoxification in L. dispar. Larval mortality, GST activity in midgut tissue and mass of L. dispar with different trophic adaptations (originating from two forests with a suitable host, Quercus robur, and an unsuitable host, Robinia pseudoacacia, differed after feeding on quercetin supplemented diets (2% or 5% w/w. Quercetin inhibited GST most potently in oak forest larvae that were less adapted to flavonoids in their diet. The larvicidal effect of quercetin on L. dispar larvae depended on the host-use history. We believe this is important in strategies for sustainable control of insect pests. [Projekat Ministarstva nauke Republike Srbije, br. 173027

The dynamics of cork oak systems in Portugal: the role of ecological and land use factors

NARCIS (Netherlands)

Acácio, V.C.

2009-01-01

Vegetation degradation and desertification occur in many semiarid ecosystems worldwide, particularly in the Western Mediterranean Basin. A peculiar semiarid Mediterranean land use system dominates the landscape of southern Portugal where cork oak (Quercus suber) is the main tree species. This system

Thinning to improve growth, bole quality, and forest health in an Inonotus hispidus-infected, red oak-sweetgum stand in the Mississippi Delta: 10-year results

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James S. Meadows; Theodor D. Leininger; David Montwé; T. Evan Nebeker

2013-01-01

A 55-year-old red oak-sweetgum (Quercus spp.- Liquidambar styraciflua) stand on the Delta National Forest in western Mississippi was subjected to a combination of low thinning and improvement cutting in 1997. Special emphasis was placed on removing all red oaks infected with Inonotus hispidus, a canker decay...

Climatically sensitive tree-ring chronologies from Crimea, Ukraine

Science.gov (United States)

Solomina, O.; Davi, N.; D Arrigo, R.

2003-04-01

Several tree species in Crimea can reach ages of 1000 years or more (Crimea..., 1999), including Taxus baccata L., Arbutus andrachne L., Quercus pubescens Willd, Quercus petraea (Mattuschka) Liebl., Quercus robur L., Juniperus excelsa M.B., and Pistacia mutica Fisch.et Mey. In September 2002, we collected samples from several long-lived tree sites described in the literature (Vulf, 1948, Ivanenko, 1951, Ena, 1983, Podgorniy, 1990), located in the mountains of Central Crimea (Sokolinoye, Chufut-Kale, Chelter) and on the coast of the Black Sea (Ai-Todor, Kharaks, Ai-Petri). The trees sampled generally had 300-350 rings. At Ai-Todor, most oaks, junipers, and pistachio showed decay. However, enough samples of oak, juniper and pine were collected to build three chronologies with good replication over the last 350 years. Long meteorological records (for Sevastopol since 1821, Ai-Petri and Yalta since the 1880's) as well as detailed historical data on extreme climatic events since 1687 (summarized by Borisov 1956) are available for this area and can be used to calibrate and verify the tree growth/climate models. Resulting dendroclimatic reconstructions will be the first from this region. The tree-ring time-series may also be used for archaeological dating of historical wood from several medieval fortresses, towns and palaces. In turn, the archaeological wood could be used to extend the tree-ring time series. Stalactites and stalagmites (Dubliansky, 1977) found in numerous caves, as well as 4000-years old laminated lake sediments (Shostakovich, 1934) are also potentially important sources of paleoclimatic information in the area.

Root morphology and growth of bare-root seedlings of Oregon white oak

Science.gov (United States)

Peter J. Gould; Constance A. Harrington

2009-01-01

Root morphology and stem size were evaluated as predictors of height and basal-area growth (measured at groundline) of 1-1 Oregon white oak (Quercus garryana Dougl. ex Hook.) seedlings planted in raised beds with or without an additional irrigation treatment. Seedlings were classified into three root classes based on a visual assessment of the...

Cesium-137 contamination of oak (Quercus petrae Liebl.) from sub-mediterranean zone in South Bulgaria

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Zhiyanski, Miglena, E-mail: zhiyanski@abv.b [Forest Ecology Department, Forest Research Institute, BAS, 132 Kliment Ohridski Blvd., 1756 Sofia (Bulgaria); Sokolovska, Maria [Forest Ecology Department, Forest Research Institute, BAS, 132 Kliment Ohridski Blvd., 1756 Sofia (Bulgaria); Bech, Jaume [Faculty of Biology, University of Barcelona, 645 Diagonal Blvd., Barcelona (Spain); Clouvas, Alexandros [Nuclear Technology Laboratory, Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, GR 54124 Thessaloniki (Greece); Penev, Ilia [Institute for Nuclear Research and Nuclear Energy, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia (Bulgaria); Badulin, Viktor [National Centre of Radiobiology and Radiation Protection, Ministry of Health, 132 Kliment Ohridski Blvd., 1756 Sofia (Bulgaria)

2010-10-15

This study focuses on the cesium-137 ({sup 137}Cs) contamination in grass and in different compartments of oak trees growing in ecosystems, located in the zone with sub-mediterranean climate in South Bulgaria, characterized with high summer temperatures, low precipitation and often periods of drought. In 2008, three experimental sites - PP1, PP2, PP3 - were sampled in oak ecosystems from Maleshevska Mountain at 900 m above sea level. Samples from grass species and oak tree leaves, branches with different diameter, wood disks and bark were analyzed for {sup 137}Cs activity with {gamma}-spectrometry. The soil-to-plant transfer factor (TF) values for {sup 137}Cs were estimated differentiating different tree compartments. Our findings showed relatively high activity concentrations of {sup 137}Cs in oak trees even 22 years after the Chernobyl accident. The grass under oak was less contaminated compared with the oak trees. The different organs of oak trees could be distinguished according to the {sup 137}Cs contamination as follows: bark > branches (d < 1 cm) > leaves > branches (d > 3 cm) > wood. The relatively higher contamination of bark compared with the new-formed biomass suggested that a significant part of {sup 137}Cs was accumulated as a result of direct adsorption at the time of the main contamination event. The TF values obtained and the presence of {sup 137}Cs in the branches, leaves and in the wood formed after 1986 confirmed that 22 years after the contamination, the main mechanism of {sup 137}Cs entrance in tree biomass was the root uptake.

The Vallarta Botanical Garden's advancements in conserving the diversity of native Mexican oaks and magnolias

Science.gov (United States)

N.A. Gerlowski; M.A. Muñiz-Castro

2017-01-01

Mexico is both an oak (Quercus) biodiversity hotspot (over 160 described species) and the western hemisphere's leader in magnolia (Magnolia) diversity (36 described species). In the face of myriad threats to these groups, including climate change, habitat loss/fragmentation, overharvesting, and plant pests/pathogens, the...

Predicting root biomass of burned and unburned white oak advance reproduction from diameter and height

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Benjamin O. Knapp; G. Geoff Wang; David H. Van Lear; Joan L. Walker

2006-01-01

The size, especially the root size, of advance oak (Quercus spp.) reproduction provides the best indication of the growth potential after release or top-kill. This study examined the relationship between the size of the root system and various diameter height measurements for small (

A 481-year chronology of oak earlywood vessels as an age-independent climatic proxy in NW Iberia

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Souto-Herrero, Manuel; Rozas, Vicente; García-González, Ignacio

2017-08-01

The earlywood vessels of ring-porous trees can be analyzed dendrochronologically and used as a proxy for environmental information. However, most works deal with the analysis of contemporary climate-growth relationships and do not evaluate their long-term variation. We obtained a 481-year chronology of earlywood vessel size of oak (Quercus robur L.) in the northwestern Iberian Peninsula, investigated its behavior through time, and compared it to a chronology of younger trees developed at the same site. We expressed earlywood vessel size as the hydraulically-weighted diameter (DH) and discriminated between vessels in the first row (r1) and the rest of the vessels (nr1); radial increment was assessed from latewood width (LW). Climate-growth relationships were strong and nearly identical for both age classes. Spring temperature positively affected vessel size, but only for the first row, probably mediating the onset of cambial activity. The chronology of old trees showed an almost flat age trend, except for the first decades, and series were not affected by stand dynamics. In contrast, LW had a weak response to climate, probably because of the high impact of abrupt growth changes. There was a high negative correlation between DH and the winter North Atlantic Oscillation Index (NAO), which was unstable during the 20th century. To our knowledge, this is the longest chronology of earlywood vessel size obtained to date, and offers promising results, as this proxy is shown to be independent of age and forest disturbances, and was strongly correlated to climate across long time spans.

Effects of fire temperature on the physical and chemical characteristics of the ash from two plots of Cork oak (Quercus Suber)

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Ubeda, X.; Pereira, P.; Outeiro, L.; Martin, D.A.

2009-01-01

Cork oak, (Quercus suber) is widely distributed in the Mediterranean region, an area subject to frequent fires. The ash produced by burning can have impacts on the soil status and water resources that can differ according to the temperature reached during fire and the characteristics of the litter, defined as the dead organic matter accumulated on the soil surface prior to the fire. The aim of this work is to determine the physical and chemical characteristics of ash produced in laboratory experiments to approximate conditions typical of fires in this region. The litter of Quercus suber collected from two different plots on the Iberian Peninsula, Mas Bassets (Catalonia) and Albufeira (Portugal), was combusted at different temperatures for 2h. We measured Mass Loss (ML per cent), ash colour and CaCO3 content, pH, Electrical Conductivity (EC) and the major cations (Ca2+, Mg2+, K+ and Na+) released from ash slurries created by mixing ash with deionized water. The results showed that ML per cent is higher at all temperatures in Albufeira samples compared to Mas Bassets samples, except at 550??C, and the rate of loss increases faster with temperature than the Mas Bassets samples. At 150??C the ash colour is yellowish, becoming reddish at 200- 250??C and black at 300??C. Above 400??C the ash is grey/white. This thermal degradation is mostly observed in Albufeira litter. The formation of CaCO3 was identified at a lower temperature in Albufeira litter. At temperatures fire. Low intensity prescribed fire can be a useful tool to land management in these sites, due to the reduced effects of fire temperatures on the physical and chemical properties of surface litter, and can reduce the risk of high temperature wildland fires by reducing fuel loadings. From the perspective of water resources, lower fire temperatures produce fewer impacts on the chemistry of overland flow and there is less probability that the soil surface will be eroded. Copyright ?? 2009 John Wiley & Sons, Ltd.

Habitat use by wild boar Sus scrofa in Moncayo Nature Park, Spain

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Rodrigues, Patrícia

2016-12-01

Full Text Available Habitat use by wild boar Sus scrofaz was examined during a three-year period in Moncayo Nature Park, a protected mountain area in the Iberian mountain system, Spain. Tracking indirect signs of activity was used to collect data on the species occurrence, according to vegetation type, topography, hunting activity, and season. The data were analysed using binary logistic regression. Habitat used by wild boar differed according seasons, management practices, and vegetation. Main selected habitats were at medium elevations (1,101-1,600 m in areas dominated by holm oak (Quercus ilex, beech (Fagus sylvatica and oak woods of Q. robur, Q. petraea and Q. pyrenaica. Non-hunting areas were selected over hunting areas. We found a seasonal variation in the habitat use of wild boar, with areas dominated by holm oak being used disproportionately in spring, and areas at medium elevations selected only during summer. The results also support the view that non-hunting areas provide a refuge for this species inside the protected area.Estudiamos el uso del hábitat por parte del jabalí Sus scrofa a lo largo de tres años en el Parque Natural del Moncayo, un área protegida de montaña en el Sistema Ibérico, España. Para ello rastreamos las huellas y señales de su actividad en función de la vegetación, topografía, actividad cinegética y estacionalidad. Los datos fueron analizados utilizando regresiones logísticas binarias. El hábitat usado por el jabalí difiere según las estaciones, gestión y vegetación. Los hábitat mayoritariamente seleccionados fueron las altitudes medias (1101-1600 m en áreas dominadas por la encina (Quercus ilex, haya (Fagus sylvatica y robles (Q. robur, Q. petraea y Q. pirenaica. Las zonas no cinegéticas fueron seleccionadas frente a las cinegéticas. Encontramos diferencias estacionales en el uso del hábitat, con un uso mayor al esperado de los encinares en primavera así como de altitudes medias durante el verano. Los

Between-Site Differences in the Scale of Dispersal and Gene Flow in Red Oak

Science.gov (United States)

Emily V Moran; James S. Clark

2012-01-01

Background: Nut-bearing trees, including oaks (Quercus spp.), are considered to be highly dispersal limited, leading to concerns about their ability to colonize new sites or migrate in response to climate change. However, estimating seed dispersal is challenging in species that are secondarily dispersed by animals, and differences in...

Relationship between precipitation and tree mortality levels in coastal California forests infested with sudden oak death

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Brent Oblinger; Zachary Heath; Jeffrey Moore; Lisa Fischer

2013-01-01

Phytophthora ramorum has caused extensive oak (Quercus) and tanoak (Notholithocarpus densiflorus (Hook. & Arn.) Manos, Cannon & S.H. Oh) mortality in portions of the central and north coasts of California. In conjunction with stream and terrestrial surveys, aerial detection surveys have played a...

Restoration of Black Oak (Quercus velutina) Sand Barrens via Three Different Habitat Management Approaches

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Kriska, David John

Disturbance regimes, i.e. frequent fires, historically maintained oak barrens until European settlement patterns, and eventually, Smoky the Bear and the fire suppression campaign of the U.S. Forest Service snuffed out the periodic flames. In the absence of a disturbance regime, ground layer floral composition at many historical oak sand barrens will change predominantly because of a buildup of leaf litter and shading of the soils. Termed mesophication, this process of ecological succession will drive Black Oak Sand Barrens to an alternate steady state. A survey conducted on Singer Lake Bog in Green, Ohio, demonstrated that succession shifted the community to red maple-black cherry woodlands more typical of a dry southern forest. In an attempt to revive disturbance, three restoration techniques were applied at ten degraded northeast Ohio oak barrens to contrast their effectiveness in restoring black oak sand barren flora. The three restoration treatments were select canopy tree reduction favoring 5% to 30% tree canopy cover, forest floor leaf litter removal, and prescribed fire. Vegetation responses to manipulations were monitored prior to and following treatment applications, and were compared against both baseline data from before-treatment surveys and paired control sites adjacent treated areas. Imposing disturbance successfully increased species diversity and abundance above that found across Singer Lake Bog compared to sampling made prior to and adjacent to treated areas. Select canopy tree removal exhibited the largest floral responses from targeted barrens species, i.e. graminoids. A forest floor invertebrate family (Carabidea: Coleoptera) was measured for species richness and abundance pre and post treatment, where a noticeable shift occurred away from woodland obligate ground beetles toward open grassland species. Replicating oak barren structure, prior to replicating disturbance processes, is the first step in the ecological restoration of these systems.

Adaptability of black walnut, black cherry, and Northern red oak to Northern California

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Philip M. McDonald

1987-01-01

When planted in sheltered sites in northern California, only 49% of black walnut (Juglans nigra L.) and 58% of black cherry (Prunus serotina Ehrh.) survived for 15 years, and 20% of northern red oak (Quercus rubra L.) survived for 10 years. The black walnut trees averaged 0.6 inches diameter at breast...

Acorn fall and weeviling in a northern red oak seedling orchard

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Daniel R. Miller; Scott E. Schlarbaum

2005-01-01

In 2000, we determined levels of damage by acorn weevils (Curculio spp.) and patterns of acorn fall in a northern red oak (Quercus rubra L.) seedling orchard in eastern Tennessee. The mean (±SE) production of acorns among 43 selected trees was 5,930 ± 586 acorns per tree with a maximum production level of 16,969 acorns for one tree...

Coast Live Oak Thinning Study in the Central Coast of California

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Norman H. Pillsbury; Michael J. DeLasaux; Timothy R. Plumb

1987-01-01

Abstract: Along-term thinning study was established in ten stands of coast live oak (Quercus agrifolia N in the Central Coast of California. Information about diameter, basal area, and volume growth and yield is being obtained from unthinned control plots and from plots thinned to 50 and 100 square feet of basal area per acre. Descriptive information was also collected...

Epicormic branching of California black oak: effect of stand and tree characteristics

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Philip M. McDonald; Martin W. Ritchie

1994-01-01

Young California black oak (Quercus kelloggii Newb.) stands usually require thinning to increase production of acorns and wood products, but epicormic branches, which yield no acorns and constitute a serious lumber degrade. often result. A crown thinning in 60-year-old hardwood stands on a south exposure at the Challenge Experimental Forest in thenorthern Sierra Nevada...

Impacts of Phytophthora ramorum on oaks and tanoaks in Marin County, California forests since 2000

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Brice A. McPherson; David L. Wood; Maggi Kelly; Sylvia R. Mori; Pavel Svihra; Andrew J. Storer; Richard B. Standiford

2010-01-01

The forests of Marin County were among the first in coastal California to be affected by the Phytophthora ramorum epidemic. Although initially observed in 1994 in tanoaks (Lithocarpus densiflorus) and 1995 in coast live oaks (Quercus agrifolia), it is evident from studies of disease progression that the...

Characterization of volatile constituents in commercial oak wood chips.

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Fernández de Simón, Brígida; Muiño, Iria; Cadahía, Estrella

2010-09-08

The volatile composition of the different oak wood pieces (chips of Quercus spp.) that can be found on the market to be used as alternatives to barrels for aging wines, as well as of chips of Quercus pyrenaica which are being introduced, was studied, evaluating the contents of volatile phenols, lactones, furanic compounds, pyranones, phenolic aldehydes, phenolic ketones, and others. In regard to the overall results, the volatile composition of these products varies widely and has not been clearly laid out according to either the oak species or the wood toasting intensity. Taking into account that the different characteristics of alternatives to barrel products are reflected in the wine treated with them and that an oenological profile based on these variables (origin and toasting level) cannot be defined, only an appropriate chemical analysis would reveal the quality of alternative-to-barrel products and allow us to attempt to foresee its effects on the chemical and organoleptic characteristics of the wines treated with them. On the other hand, the Q. pyrenaica alternative products are very similar to those of other species, with some aromatic particularities, such as their high levels of furanic compounds, eugenol, Furaneol, and cis-whiskylactone, and low levels of vanillin.

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

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Scott R. Abella; Peter Z. Fulé

2008-01-01

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

Genetic Structure and Evolutionary History of Three Alpine Sclerophyllous Oaks in East Himalaya-Hengduan Mountains and Adjacent Regions.

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Feng, Li; Zheng, Qi-Jian; Qian, Zeng-Qiang; Yang, Jia; Zhang, Yan-Ping; Li, Zhong-Hu; Zhao, Gui-Fang

2016-01-01

The East Himalaya-Hengduan Mountains (EH-HM) region has a high biodiversity and harbors numerous endemic alpine plants. This is probably the result of combined orographic and climate oscillations occurring since late Tertiary. Here, we determined the genetic structure and evolutionary history of alpine oak species (including Quercus spinosa, Quercus aquifolioides , and Quercus rehderiana ) using both cytoplasmic-nuclear markers and ecological niche models (ENMs), and elucidated the impacts of climate oscillations and environmental heterogeneity on their population demography. Our results indicate there were mixed genetic structure and asymmetric contemporary gene flow within them. The ENMs revealed a similar demographic history for the three species expanded their ranges from the last interglacial (LIG) to the last glacial maximum (LGM), which was consistent with effective population sizes changes. Effects of genetic drift and fragmentation of habitats were responsible for the high differentiation and the lack of phylogeographic structure. Our results support that geological and climatic factors since Miocene triggered the differentiation, evolutionary origin and range shifts of the three oak species in the studied area and also emphasize that a multidisciplinary approach combining molecular markers, ENMs and population genetics can yield deep insights into diversification and evolutionary dynamics of species.

Ethanol attracts scolytid beetles to Phytophthora ramorum cankers on coast live oak [Abstract

Science.gov (United States)

Rick G. Kelsey; Maia Beh; Dave Shaw; Daniel K. Manter

2013-01-01

Successful infection of coast live oak (Quercus agrifolia Née) stems by Phytophthora ramorum results in the formation of a canker visible initially at the bark surface by the release of a dark red to black colored exudate referred to as "bleeding." Bark and ambrosia beetles are often attracted to diseased trees within...

Applying Hotspot Detection Methods in Forestry: A Case Study of Chestnut Oak Regeneration

International Nuclear Information System (INIS)

Fei, S.

2010-01-01

Hotspot detection has been widely adopted in health sciences for disease surveillance, but rarely in natural resource disciplines. In this paper, two spatial scan statistics (SaT Scan and Cluster Seer) and a non spatial classification and regression trees method were evaluated as techniques for identifying chestnut oak (Quercus Montana) regeneration hotspots among 50 mixed-oak stands in the central Appalachian region of the eastern United States. Hotspots defined by the three methods had a moderate level of conformity and revealed similar chestnut oak regeneration site affinity. Chestnut oak regeneration hotspots were positively associated with the abundance of chestnut oak trees in the over story and a moderate cover of heather species (Vaccinium and Gaylussacia spp.) but were negatively associated with the abundance of hay scented fern (Dennstaedtia punctilobula) and mountain laurel (Kalmia latiforia). In general, hotspot detection is a viable tool for assisting natural resource managers with identifying areas possessing significantly high or low tree regeneration.

Applying Hotspot Detection Methods in Forestry: A Case Study of Chestnut Oak Regeneration

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Songlin Fei

2010-01-01

Full Text Available Hotspot detection has been widely adopted in health sciences for disease surveillance, but rarely in natural resource disciplines. In this paper, two spatial scan statistics (SaTScan and ClusterSeer and a nonspatial classification and regression trees method were evaluated as techniques for identifying chestnut oak (Quercus Montana regeneration hotspots among 50 mixed-oak stands in the central Appalachian region of the eastern United States. Hotspots defined by the three methods had a moderate level of conformity and revealed similar chestnut oak regeneration site affinity. Chestnut oak regeneration hotspots were positively associated with the abundance of chestnut oak trees in the overstory and a moderate cover of heather species (Vaccinium and Gaylussacia spp. but were negatively associated with the abundance of hayscented fern (Dennstaedtia punctilobula and mountain laurel (Kalmia latiforia. In general, hotspot detection is a viable tool for assisting natural resource managers with identifying areas possessing significantly high or low tree regeneration.

A new genus of oak gallwasp, Cyclocynips Melika, Tang & Sinclair (Hymenoptera: Cynipidae: Cynipini), with descriptions of two new species from Taiwan.

Science.gov (United States)

Melika, George; Tang, Chang-ti; Sinclair, Frazer; Yang, Man-miao; Lohse, Konrad; Hearn, Jack; Nicholls, James A; Stone, Graham N

2013-01-01

A new genus of cynipid oak gallwasp-Cyclocynips Melika, Tang, & Sinclair (Hymenoptera: Cynipidae: Cynipini), with two new species--C. uberis and C. tumorvirgae--reared from galls on oaks of the Quercus subgenus Cyclobalanopsis is described from Taiwan. Descriptions of asexual generation adults and their diagnostic characters are presented. The likelihood of yet undiscovered sexual generations and the evolution of host-plant associations in these species are discussed.

Mass loss and nutrient concentrations of buried wood as a function of organic matter removal, soil compaction, and vegetation control in a regenerating oak-pine forest

Science.gov (United States)

Felix Ponder; John M. Kabrick; Mary Beth Adams; Deborah S. Page-Dumroese; Marty F. Jurgensen

2017-01-01

Mass loss and nutrient concentrations of northern red oak (Quercus rubra) and white oak (Q. alba) wood stakes were measured 30 months after their burial in the upper 10 cm of soil in a regenerating forest after harvesting and soil disturbance. Disturbance treatments were two levels of organic matter (OM) removal (only...

Improving the phytoremediation of heavy metals contaminated soil by use of sewage sludge.

Science.gov (United States)

Placek, Agnieszka; Grobelak, Anna; Kacprzak, Malgorzata

2016-01-01

Sewage sludge, in particular from the food industry, is characterized by fertilizing properties, due to the high content of organic matter and nutrients. The application of sewage sludge causes an improvement of soil parameters as well as increase in cation exchange capacity, and thus stronger binding of cations in the soil environment, which involves the immobilization of nutrients and greater resistance to contamination. In a field experiment sewage sludge has been used as an additive to the soil supporting the phytoremediation process of land contaminated with heavy metals (Cd, Zn, and Pb) using trees species: Scots pine (Pinus silvestris L.), Norway spruce (Picea abies L.), and oak (Quercus robur L.). The aim of the research was to determine how the application of sewage sludge into the soil surface improves the phytoremediation process. The conducted field experiment demonstrated that selected trees like Scots pine and Norway spruce, because of its excellent adaptability, can be used in the remediation of soil. Oak should not be used in the phytoremediation process of soils contaminated with high concentrations of trace elements in the soil, because a significant amount of heavy metals was accumulated in the leaves of oak causing a risk of recontamination.

Variations in Environmental Signals in Tree-Ring Indices in Trees with Different Growth Potential.

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Polona Hafner

Full Text Available We analysed two groups of Quercus robur trees, growing at nearby plots with different micro-location condition (W-wet and D-dry in the floodplain Krakovo forest, Slovenia. In the study we compared the growth response of two different tree groups to environmental variables, the potential signal stored in earlywood (EW structure and the potential difference of the information stored in carbon isotope discrimination of EW and latewood (LW. For that purpose EW and LW widths and carbon isotope discrimination for the period 1970-2008 AD were measured. EW and LW widths were measured on stained microscopic slides and chronologies were standardised using the ARSTAN program. α-cellulose was extracted from pooled EW and LW samples and homogenized samples were further analysed using an elemental analyser and IRMS. We discovered that W oaks grew significantly better over the whole analysed period. The difference between D and W oaks was significant in all analysed variables with the exception of stable carbon isotope discrimination in latewood. In W oaks, latewood widths correlated with summer (June to August climatic variables, while carbon isotope discrimination was more connected to River Krka flow during the summer. EW discrimination correlated with summer and autumn River Krka flow of the previous year, while latewood discrimination correlated with flow during the current year. In the case of D oaks, the environmental signal appears to be vague, probably due to less favourable growth conditions resulting in markedly reduced increments. Our study revealed important differences in responses to environmental factors between the two oak groups of different physiological conditions that are preconditioned by environmental stress. Environmental information stored in tree-ring features may vary, even within the same forest stand, and largely depends on the micro-environment. Our analysis confirmed our assumptions that separate EW and LW analysis of widths and

Impact of tree species on soil carbon stocks and soil acidity in southern Sweden

International Nuclear Information System (INIS)

Oostra, Swantje; Majdi, Hooshang; Olsson, Mats

2006-01-01

The impact of tree species on soil carbon stocks and acidity in southern Sweden was studied in a non-replicated plantation with monocultures of 67-year-old ash (Fraxinus excelsior L.), beech (Fagus silvatica L.), elm (Ulmus glabra Huds.), hornbeam (Carpinusbetulus L.), Norway spruce (Picea abies L.) and oak (Quercus robur L.). The site was characterized by a cambisol on glacial till. Volume-determined soil samples were taken from the O-horizon and mineral soil layers to 20 cm. Soil organic carbon (SOC), total nitrogen (TN), pH (H2O), cation-exchange capacity and base saturation at pH 7 and exchangeable calcium, magnesium, potassium and sodium ions were analysed in the soil fraction hornbeam > oak > beech > ash > elm. The pH in the O-horizon ranged in the order elm > ash > hornbeam > beech > oak > spruce. In the mineral soil, SOC and TN ranged in the order elm > oak > ash = hornbeam > spruce > beech, i.e. partly reversed, and pH ranged in the same order as for the O-horizon. It is suggested that spruce is the best option for fertile sites in southern Sweden if the aim is a high carbon sequestration rate, whereas elm, ash and hornbeam are the best solutions if the aim is a low soil acidification rate

Development of molecular markers for determining continental origin of wood from White Oaks (Quercus L. sect. Quercus)

Science.gov (United States)

Hilke Schroeder; Richard Cronn; Yulai Yanbaev; Tara Jennings; Malte Mader; Bernd Degen; Birgit Kersten; Dusan Gomory

2016-01-01

To detect and avoid illegal logging of valuable tree species, identification methods for the origin of timber are necessary. We used next-generation sequencing to identify chloroplast genome regions that differentiate the origin of white oaks from the three continents; Asia, Europe, and North America. By using the chloroplast genome of Asian Q. mongolica...

Bacteria associated with oak and ash on a TCE-contaminated site: characterization of isolates with potential to avoid evapotranspiration of TCE.

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Weyens, Nele; Taghavi, Safiyh; Barac, Tanja; van der Lelie, Daniel; Boulet, Jana; Artois, Tom; Carleer, Robert; Vangronsveld, Jaco

2009-11-01

Along transects under a mixed woodland of English Oak (Quercus robur) and Common Ash (Fraxinus excelsior) growing on a trichloroethylene (TCE)-contaminated groundwater plume, sharp decreases in TCE concentrations were observed, while transects outside the planted area did not show this remarkable decrease. This suggested a possibly active role of the trees and their associated bacteria in the remediation process. Therefore, the cultivable bacterial communities associated with both tree species growing on this TCE-contaminated groundwater plume were investigated in order to assess the possibilities and practical aspects of using these common native tree species and their associated bacteria for phytoremediation. In this study, only the cultivable bacteria were characterized because the final aim was to isolate TCE-degrading, heavy metal resistant bacteria that might be used as traceable inocula to enhance bioremediation. Cultivable bacteria isolated from bulk soil, rhizosphere, root, stem, and leaf were genotypically characterized by amplified rDNA restriction analysis (ARDRA) of their 16S rRNA gene and identified by 16S rRNA gene sequencing. Bacteria that displayed distinct ARDRA patterns were screened for heavy metal resistance, as well as TCE tolerance and degradation, as preparation for possible future in situ inoculation experiments. Furthermore, in situ evapotranspiration measurements were performed to investigate if the degradation capacity of the associated bacteria is enough to prevent TCE evapotranspiration to the air. Between both tree species, the associated populations of cultivable bacteria clearly differed in composition. In English Oak, more species-specific, most likely obligate endophytes were found. The majority of the isolated bacteria showed increased tolerance to TCE, and TCE degradation capacity was observed in some of the strains. However, in situ evapotranspiration measurements revealed that a significant amount of TCE and its metabolites

Predicting stump sprouting and competitive success of five oak species in southern Indiana

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Dale R. Weigel; Chao-Ying Joanne Peng

2002-01-01

We measured 2188 oak trees (Quercus spp.) on the Hoosier National Forest in southern Indiana before and 1, 5, and 10 years after clear-cutting to determine the influence of parent tree age, diameter breast height, and site index on the probability that there was one or more living sprouts per stump: (i) 1 year after clear-cutting (sprouting...

Influence of pericarp, cotyledon and inhibitory substances on sharp tooth oak (Quercus aliena var. acuteserrata germination.

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Yan Liu

Full Text Available In order to explore the mechanism of delayed and uneven germination in sharp tooth oak (Quercus aliena var. acuteserrata (STO, mechanical scarification techniques were used to study STO root and shoot germination and growth. The techniques used were: removing cup scar (RS, removing the pericarp (RP, and cutting off 1/2 (HC and 2/3 (TC cotyledons. Germination percentage and root and shoot length for Chinese cabbage (Beassica pekinensis seeds (CCS were also investigated for CCS cultivated in a Sanyo growth cabinet watered by distilled water and 80% methanol extracts from the acorn embryo, cotyledon and pericarp with concentrations of 1.0 g, 0.8 g, 0.6 g and 0.4 g dry acorn weight per ml methanol. The results showed that the majority of roots and shoots from acorns with RP and HC treatment emerged two weeks earlier, more simultaneously, and their total emergencies were more than 46% and 28% higher, respectively. TC accelerated root and shoot emergence time and root length, but root and shoot germination rate and shoot height had no significant difference from the control. Positive consequences were not observed on all indices of RS treatment. The germination rates of CCS watered by 1.0 g · ml(-1 methanol extracts from the embryo and cotyledon were significantly lower than those from the pericarp, and all concentrations resulted in decreased growth of root and shoot. Methanol extracts from pericarp significantly reduced root length of CCS, but presented little response in germination percentage and shoot length. The inhibitory effect was gradually increased with the increasing concentration of the methanol extract. We conclude that both the mechanical restriction of the pericarp and the presence of germination inhibitors in the embryo, cotyledon and pericarp are the causes for delayed and asynchronous germination of STO acorns.

Within-population variation in response of red oak seedlings to herbivory by gypsy moth larvae

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T. Scott Byington; Kurt W. Gottschalk; James B. McGraw

1994-01-01

The potential for an evolutionary response to gypsy moth (Lymantna dispar L.) herbivory was investigated in red oak (Quercus rubra L.), a preferred host. Seedlings of nine open-pollinated families were grown in a greenhouse and experimentally defoliated by fourth instar larvae in the summer of 1991 to assay for intraspecific...

Effects of Mechanical Site Preparation on Growth of Oaks Planted on Former Agricultural Fields

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John D. Hodges

2011-12-01

Full Text Available Mechanical site preparation is frequently proposed to alleviate problematic soil conditions when afforesting retired agricultural fields. Without management of soil problems, any seedlings planted in these areas may exhibit poor growth and survival. While mechanical site preparation methods currently employed in hardwood afforestation are proven, there is a substantial void in research comparing subsoiling, bedding, and combination plowing treatments. A total of 4,320 bare-root Nuttall oak (Quercus texana Buckley, Shumard oak (Quercus shumardii Buckley, and swamp chestnut oak (Quercus michauxii Nutt. seedlings were planted in February 2008 on three Mississippi sites. All sites were of comparable soils and received above average precipitation throughout the three-year duration of the study. Four site preparation treatments were replicated at each site, with 480 seedlings planted in each of nine replications, and a total of 1,440 seedlings per species planted across all sites. Mechanical treatments were installed using 3.1 m row centers, with treatments as follows: control, subsoiling, bedding, and combination plowing. Treatment effects on seedling height, groundline diameter (GLD, and survival were analyzed. Seedlings exhibited greater height in bedded and combination plowed areas (79.7 cm to 102.7 cm and 82.6 cm to 100.1 cm, respectively compared to subsoiled or control areas (70.4 cm to 84.6 cm and 71.4 cm to 86.9 cm, respectively. Greater GLD was observed in bedded and combination plowed areas (11.9 mm to 18.4 mm and 12.2 mm to 18.3 mm, respectively compared to subsoiled or control areas (10.2 mm to 14.6 mm and 10.5 mm to 15.6 mm, respectively. Survival was high for this study (94.%, and no differences were detected among treatments.

Saccharomyces jurei sp. nov., isolation and genetic identification of a novel yeast species from Quercus robur.

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Naseeb, Samina; James, Stephen A; Alsammar, Haya; Michaels, Christopher J; Gini, Beatrice; Nueno-Palop, Carmen; Bond, Christopher J; McGhie, Henry; Roberts, Ian N; Delneri, Daniela

2017-06-01

Two strains, D5088T and D5095, representing a novel yeast species belonging to the genus Saccharomyces were isolated from oak tree bark and surrounding soil located at an altitude of 1000 m above sea level in Saint Auban, France. Sequence analyses of the internal transcribed spacer (ITS) region and 26S rRNA D1/D2 domains indicated that the two strains were most closely related to Saccharomyces mikatae and Saccharomyces paradoxus. Genetic hybridization analyses showed that both strains are reproductively isolated from all other Saccharomyces species and, therefore, represent a distinct biological species. The species name Saccharomyces jurei sp. nov. is proposed to accommodate these two strains, with D5088T (=CBS 14759T=NCYC 3947T) designated as the type strain.

THE EFFECT OF MAGNETIC LIQUIDS IN SOME TREE SEEDLINGS

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Ioan Creanga

2005-08-01

Full Text Available The seedlings of two tree species, the black poplar hybrid (Populus canadiensis Moench. and the pedunculate oak (Quercus robur L., among the most important for the temperate region, were treated with various concentrations of oil-ferrofluid based on natural hydrocarbons. The experiment has revealed the ferrofluid influence on the assimilatory pigments as well as on the nucleic acids (spectral measurements in young plantlets aged of 3 months. It was found that the levels of assimilatory pigments are generally diminished though the ratio chlorophyll a/chlorophyll b is generally enhanced for ferrofluid samples suggesting the seedlings sensitivity to the chemical and magnetic stimuli consistent with the ferrofuid addition. The LHC II system (Light Harvesting Complex II sensitivity to external factors might be associated with the ferrofluid influence on the young seedlings photosynthesis.

Approaches to restoration of oak forests on farmed lowlands of the Mississippi River and its tributaries

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Emile S. Gardiner; Daniel C. Dey; John A. Stanturf; Brian Roy. Lockhart

2010-01-01

The lowlands associated with the Mississippi River and its tributaries historically supported extensive broadleaf forests that were particularly rich in oak (Quercus spp.) species. Beginning in the 1700s, deforestation for agriculture substantially reduced the extent of the original forest, and fragmented the remainder into small parcels. More...

An analysis of phenotypic selection in natural stands of northern red oak (Quercus rubra L.)

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Jeffery W. Stringer; David B. Wagner; Scott E. Schlarbaum; Daniel B. Houston

1995-01-01

Comparison of growth and stem quality parameters of 19-year-old progeny from superior and comparison trees indicates that rigorous phenotypic selection of trees in natural stands may not be an efficient method of parent tree selection for Quercus rubra L. Total tree height, dbh, number of branches in the butt log, fork height, and number of mainstem...

Can prescribed fires be used to promote the recruitment of white oak (Quercus alba) seedlings?

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G. Geoff Wang; David H. Van Lear; William L. Bauerie

2006-01-01

Widespread oak replacement by mesophytic tree species, especially on good quality sites, has been occurring across the Eastern United States, because advance oak reproduction is severely limited by the development of heavy midstory and understory. Anecdotal evidence suggests that the development of heavy midstory and understory coincides with the implementation of a...

Spring temperature responses of oaks are synchronous with North Atlantic conditions during the last deglaciation

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Steven L. Voelker; Paul-Emile Noirot-Cosson; Michael C. Stambaugh; Erin R. McMurry; Frederick C. Meinzer; Barbara Lachenburch; Richard P. Guyette

2012-01-01

Paleoclimate proxies based on the measurement of xylem cell anatomy have rarely been developed across the temperature range of a species or applied to wood predating the most recent millennium. Here we describe wood anatomy-based proxies for spring temperatures in central North America from modern bur oaks (Quercus macrocarpa Michx.). The strong...

Blue oak plant communities of southern San Luis Obispo and northern Santa Barbara Counties, California

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Mark I. Borchert; Nancy D. Cunha; Patricia C. Krosse; Marcee L. Lawrence

1993-01-01

An ecological classification system has been developed for the Pacific Southwest Region of the Forest Service. As part of that classification effort, blue oak (Quercus douglasii) woodlands and forests of southern San Luis Obispo and northern Santa Barbara Counties in Los Padres National Forest were classified into I3 plant communities using...

Growth and mortality of pin oak and pecan reforestation in a constructed wetland: analysis with management implications

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D.E. Henderson; P. Botch; J. Cussimanio; D. Ryan; J. Kabrick; D. Dey

2009-01-01

Pin oak (Quercus palustris Muenchh.) and pecan (Carya illinoensis (Wangenh.) K. Koch) trees were planted on reforestation plots at Four Rivers Conservation Area in west-central Missouri. The study was conducted to determine survival and growth rates of the two species under different production methods and environmental variables....

Sapwood area as an estimator of leaf area and foliar weight in cherrybark oak and green ash

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James S. Meadows; John D. Hodges

2002-01-01

The relationships between foliar weight/leaf area and four stem dimensions (d.b.h., total stem cross-sectional area, total sapwood area, and current sapwood area at breast height) were investigated in two important bottomland tree species of the Southern United States, cherrybark oak (Quercus falcata var. pagodifolia ...

Growth-Climate Response of Young Turkey Oak (Quercus cerris L. Coppice Forest Stands along Longitudinal Gradient in Albania

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Merita Stafasani

2015-06-01

Full Text Available Background and Purpose: Turkey oak (Quercus cerris L. is the most widespread species in Albania and less investigated from dendroclimatological point of view. Previous studies have reported that Q. cerris is sensitive to the environment when growing at different latitudes and ecological conditions. Based on this fact we have explored the response of different Q. cerris populations located along the longitudinal gradient. Materials and Methods: The stem discs were sampled from six sites (Kukes, Diber, Rreshen, Ulez, Elbasan, Belsh along longitudinal gradient ranging from north-east to central Albania. All oak forests stands grow under the influence of specific local Mediterranean climate. Tree-ring widths were measured to the nearest 0.001 mm using a linear table, LINTAB and the TSAP-Win program. Following the standard dendrochronological procedures residual tree-ring width chronologies were built for each site. Statistical parameters commonly used in dendrochronology were calculated for each site chronology. Relations between the tree-ring chronologies were explored using Hierarchical Factor Classification (HFC and Principal Component Analysis (PCA, while the radial growth-climate relationship was analyzed through correlation analysis using a 19-month window from April in the year prior to tree-ring formation (year t - 1 until October in the year of growth (year t. Results and Conclusions: The length of the site chronologies ranged from 16 to 36 years, with the Elbasan site chronology being the longest and the Belsh site chronology the shortest one. Trees at lower elevation were younger than trees at higher elevation. Statistical parameters (mean sensitivity (MS and auto correlation (AC of site chronologies were different among them and lower values of AC1 showed a weaker dependence of radial growth from climatic conditions of the previous growing year. Principal component analysis showed that Belsh, Rreshen and Elbasan site chronologies were

Germination of hyphal bodies of Pythium spiculum isolated from declining cork oaks at Doñana National Park (Spain

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PAOLO DE VITA

2012-01-01

Full Text Available Pythium spiculum, a recently described new taxon, has been isolated from declining cork oaks (Quercus suber L. at Doñana National Park (south-western Spain. The microorganism can infect and cause root disease in Quercus, but currently it is unknown whether its hyphal bodies can germinate and infect host trees. These hyphal bodies, regardless of shape, have been shown to be able to germinate, producing long germ tubes, sometimes ramified. Zoospore production was not recorded, but hyphal bodies are potential host infective structures in dry soil conditions.

Increase of radiocarbon concentration in tree rings from Kujawy (SE Poland) around AD 774-775

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Rakowski, Andrzej Z.; Krąpiec, Marek; Huels, Mathias; Pawlyta, Jacek; Dreves, Alexander; Meadows, John

2015-10-01

Evidence of a rapid increase in atmospheric radiocarbon (14C) content in AD 774-775 was presented by Miyake et al. (2012), who observed an increase of about 12‰ in the 14C content in annual tree rings from Japanese cedar. Usoskin et al. (2013) report a similar 14C spike in German oak, and attribute it to exceptional solar activity. If this phenomenon is global in character, such rapid changes in 14C concentration may affect the accuracy of calibrated dates, as the existing calibration curve is composed mainly of decadal samples. Single-year samples of dendro-chronologically dated tree rings of deciduous oak (Quercus robur) from Kujawy, a village near Krakow (SE Poland), spanning the years AD 765-796, were collected and their 14C content was measured using the AMS system in the Leibniz Laboratory. The results clearly show a rapid increase of 9.2 ± 2.1‰ in the 14C concentration in tree rings between AD 774 and AD 775, with maximum Δ14C = 4.1 ± 2.3‰ noted in AD 776.

Oak conservation and restoration on private forestlands: negotiating a social-ecological landscape.

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Knoot, Tricia G; Schulte, Lisa A; Rickenbach, Mark

2010-01-01

In the midwestern United States, oak (Quercus spp.) forests are considered critical habitat for conserving biodiversity and are a declining resource. Ecological conditions, such as deer herbivory and competition from more mesic broad-leaved deciduous species, have been linked to poor oak regeneration. In the Midwest, where up to 90% of forestland is privately owned, a greater understanding of social dimensions of oak regeneration success is especially critical to designing effective restoration strategies. We sought to determine factors that serve as direct and indirect constraints to oak restoration and identify policy mechanisms that could improve the likelihood for restoration success. We conducted in-depth qualitative interviews with 32 natural resource professionals working in the Midwest Driftless Area. We found that most professionals anticipate that oak will remain only a component of the future forest. Furthermore, they identified the general unwillingness of landowners to adopt oak restoration practices as a primary driving force of regional forest change. The professionals pointed to interdependent ecological and social factors, occurring at various scales (e.g., economic cost of management, deer herbivory, and exurban residential development) as influencing landowner oak restoration decisions. Professionals emphasized the importance of government cost-share programs and long-term personal relationships to securing landowner acceptance of oak restoration practices. However, given finite societal resources, ecologically- and socially-targeted approaches were viewed as potential ways to optimize regional success.

Origin, development, and impact of mountain laurel thickets on the mixed-oak forests of the central Appalachian Mountains, USA

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Patrick H. Brose

2016-01-01

Throughout forests of the northern hemisphere, some species of ericaceous shrubs can form persistent understories that interfere with forest regeneration processes. In the Appalachian Mountains of eastern North America, mountain laurel (Kalmia latifolia) may interfere in the regeneration of mixed-oak (Quercus spp.) forests. To...

Winter season corticular photosynthesis in Cornus florida, Acer rubrum, Quercus alba, and Liriodendron tulipifera

International Nuclear Information System (INIS)

Coe, J.M.; McLaughlin, S.B.

1980-01-01

Winter season corticular photosynthesis was studied in four species of deciduous trees: dogwood (Cornus florida), red maple (Acer rubrum), white oak (Quercus alba), and yellow-poplar (Liriodendron tulipifera). Techniques included measuring CO 2 uptake at varying light intensities, relating the apparent photosynthetic capacities to seasonal changes in chlorophyll content of twigs and determining the fate of assimilated carbon over time. Dogwood was the most photosynthetically active of the four species studied; however, gross photosynthesis did not exceed respiration in any of the four species. Photosynthetic activity of dogwood twigs was estimated at 10% of that of dogwood leaves on a weight basis and 85% on a surface area basis. Photosynthetic activity was generally related to shade tolerance ranking and was on the order of dogwood much greater than red maple much greater than white oak approx. = yellow-poplar. Little change in chlorophyll content occurred over the January-April 1979 study interval

Comparative study on the catalase activity in grassy and forestry plants exposed to low gamma radiation

International Nuclear Information System (INIS)

Arteni, A. A; Mocanasu, R. C.; Arteni, V.; Creanga, I.

2001-01-01

Since gamma rays level in atmosphere occasionally increases affecting biosphere,the radiation effect damages seriously certain plant species. This study was focused on a grassy species,Triticum aestivum, in comparison to a forestry species, namely Quercus robur. Young plantlets were exposed to weak gamma rays delivered by a laboratory 60 Co source, for different irradiation times. The enzymatic activity of catalase was evaluated using biochemical methods. Triticum aestivum presented a slight enhancing of catalase, both in caryopsides and leafs. Quercus robur revealed a rapid linear enhancing of catalase in saplings cultivated in laboratory while saplings grown in forestry were characterized by a reduced catalase activity. Concurrent phenomena of enzyme biosynthesis stimulation and enzyme structure damage are presumed to be the cause of such behavior. (authors)

Leaf area compounds height-related hydraulic costs of water transport in Oregon White Oak trees.

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N. Phillips; B. J. Bond; N. G. McDowell; Michael G. Ryan; A. Schauer

2003-01-01

The ratio of leaf to sapwood area generally decreases with tree size, presumably to moderate hydraulic costs of tree height. This study assessed consequences of tree size and leaf area on water flux in Quercus garryana Dougl. ex. Hook (Oregon White Oak), a species in which leaf to sapwood area ratio increases with tree size. We tested hypotheses that...

Red Oak Research and Demonstration Area in Phelps Township, North Bay, Ontario-2004 to 2005

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Dave Deugo; Andrée Morneault; Dianne Othmer; Megan Smith; Al Stinson; Murray Woods; Ian Kovacs; Ian Aho; Bill Parker; Rob Baker; Marinus Verwey; Guylaine Thauvette; Don Willis; Jeff Dech

2006-01-01

In July 2004, a large stand of red oak (Quercus rubra) was harvested in Phelps Township, North Bay District, North Bay, Ontario using the uniform shelterwood system. Most of the stand was harvested to retain 40 percent crown closure, while a very small portion was harvested to retain 70 percent crown closure. During tree marking, an active Northern...

A dendrochronological analysis of a disturbance-succession model for oak-pine forests of the Appalachian Mountains, USA

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Patrick H. Brose; Thomas A. Waldrop

2010-01-01

Disturbance-succession models describe the relationship between the disturbance regime and the dominant tree species of a forest type. Such models are useful tools in ecosystem management and restoration, provided they are accurate. We tested a disturbance-succession model for the oak-pine (Quercus spp. - Pinus spp.) forests of the...

Word-wide meta-analysis of Quercus forests ectomycorrhizal fungal diversity reveals southwestern Mexico as a hotspot.

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García-Guzmán, Olimpia Mariana; Garibay-Orijel, Roberto; Hernández, Edith; Arellano-Torres, Elsa; Oyama, Ken

2017-11-01

Quercus is the most diverse genus of ectomycorrhizal (ECM) host plants; it is distributed in the Northern and Southern Hemispheres, from temperate to tropical regions. However, their ECM communities have been scarcely studied in comparison to those of conifers. The objectives of this study were to determine the richness of ECM fungi associated with oak forests in the Cuitzeo basin in southwestern Mexico; and to determine the level of richness, potential endemism and species similarity among ECM fungal communities associated with natural oak forests worldwide through a meta-analysis. The ITS DNA sequences of ECM root tips from 14 studies were included in the meta-analysis. In total, 1065 species of ECM fungi have been documented worldwide; however, 812 species have been only found at one site. Oak forests in Europe contain 416 species, Mexico 307, USA 285, and China 151. Species with wider distributions are Sebacinaceae sp. SH197130, Amanita subjunquillea, Cenococcum geophilum, Cortinarius decipiens, Russula hortensis, R. risigallina, R. subrubescens, Sebacinaceae sp. SH214607, Tomentella ferruginea, and T. lapida. The meta-analysis revealed (1) that Mexico is not only a hotspot for oak species but also for their ECM mycobionts. (2) There is a particularly high diversity of ECM Pezizales in oak seasonal forests from western USA to southwestern Mexico. (3) The oak forests in southwestern Mexico have the largest number of potential endemic species. (4) Globally, there is a high turnover of ECM fungal species associated with oaks, which indicates high levels of alpha and beta diversity in these communities.

The Effect of Low Oxygen Stress on Phytophthora cinnamomi Infection and Disease of Cork Oak Roots

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Karel A. Jacobs; James D. MacDonald; Alison M. Berry; Laurence R. Costello

1997-01-01

The incidence and severity of Phytophthora cinnamomi Rands root disease was quantified in cork oak (Quercus suber L.) roots subjected to low oxygen (hypoxia) stress. Seedling root tips were inoculated with mycelial plugs of the fungus and incubated in ≤1, 3-4, or 21 percent oxygen for 5 days. Ninety-four percent of roots...

Effect of directed-spray glyphosate applications on survival and growth of planted oaks after three growing seasons

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Andrew B. Self; Andrew W. Ezell; Josh L. Moree; Rory O. Thornton

2013-01-01

Thousands of acres of oak (Quercus spp.) plantations are established across the South annually. Survival and growth of these plantings have been less than desirable. Several techniques have been utilized in attempts to achieve improved success in these areas. One such technique that has been recommended is the application of directed-spray herbicide...

Behavioral assumptions of conservation policy: conserving oak habitat on family-forest land in the Willamette Valley, Oregon

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A. Paige Fischer; John C. Bliss

2008-01-01

Designing policies that harness the motivations of landowners is essential for conserving threatened habitats on private lands. Our goal was to understand how to apply ethnographic information about family-forest owners to the design of conservation policy for Oregon white oak (Quercus garryana) in the Willamette Valley, Oregon (U.S.A.). We examined...

Phenotypic variation in California populations of valley oak (Quercus lobata Née) sampled along elevational gradients

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Ana L. Albarrán-Lara; Jessica W. Wright; Paul F. Gugger; Annette Delfino-Mix; Juan Manuel Peñaloza-Ramírez; Victoria L. Sork

2015-01-01

California oaks exhibit tremendous phenotypic variation throughout their range. This variation reflects phenotypic plasticity in tree response to local environmental conditions as well as genetic differences underlying those phenotypes. In this study, we analyze phenotypic variation in leaf traits for valley oak adults sampled along three elevational transects and in...

Environmental Assessment for the Aeromedical Evacuation Formal Training Unit, Wright-Patterson Air Force Base

Science.gov (United States)

2012-05-01

pennsylvanica), White Ash (Fraxinus americana), Shingle Oak (Quercus imbricaria), Northern Red Oak (Quercus rubra), Slippery Elm (Ulmus rubra...American Elm (Ulmus americana), Eastern Cottonwood (Populus deltoides), Silver Maple (Acer saccharinum), Sassafras (Sassafras albidum), Post Oak (Quercus

Restoring sand shinnery oak prairies with herbicide and grazing in New Mexico

Science.gov (United States)

Zavaleta, Jennifer C.; Haukos, David A.; Grisham, Blake A.; Boal, Clint W.; Dixon, Charles

2016-01-01

Sand shinnery oak (Quercus havardii) prairies are increasingly disappearing and increasingly degraded in the Southern High Plains of Texas and New Mexico. Restoring and managing sand shinnery oak prairie can support biodiversity, specific species of conservation concern, and livestock production. We measured vegetation response to four treatment combinations of herbicide (tebuthiuron applied at 0.60 kg/ha) and moderate-intensity grazing (50% removal of annual herbaceous production) over a 10-year period in a sand shinnery oak prairie of eastern New Mexico. We compared the annual vegetation response to the historical climax plant community (HCPC) as outlined by the U.S. Department of Agriculture Ecological Site Description. From 2 to 10 years postapplication, tebuthiuron-treated plots had reduced shrub cover with twice as much forb and grass cover as untreated plots. Tebuthiuron-treated plots, regardless of the presence of grazing, most frequently met HCPC. Tebuthiuron and moderate-intensity grazing increased vegetation heterogeneity and, based on comparison of the HCPC, successfully restored sand shinnery oak prairie to a vegetation composition similar to presettlement.

Estimating mast production: an evaluation of visual surveys and comparison with seed traps using white oaks

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Roger W. Perry; Ronald E. Thill

1999-01-01

Perry and Thill compared five types of visual mast surveyed with seed trap data from 105 white oaks (Quercus alba L.) during 1996-1997 in the Ouachita Mountains of Arkansas. They also evaluated these visual survey methods for their usefulness in detecting differences in acorn density among areas. Indices derived from all five methods were highly...

Water-use strategies in two co-occurring Mediterranean evergreen oaks: surviving the summer drought.

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David, T S; Henriques, M O; Kurz-Besson, C; Nunes, J; Valente, F; Vaz, M; Pereira, J S; Siegwolf, R; Chaves, M M; Gazarini, L C; David, J S

2007-06-01

In the Mediterranean evergreen oak woodlands of southern Portugal, the main tree species are Quercus ilex ssp. rotundifolia Lam. (holm oak) and Quercus suber L. (cork oak). We studied a savannah-type woodland where these species coexist, with the aim of better understanding the mechanisms of tree adaptation to seasonal drought. In both species, seasonal variations in transpiration and predawn leaf water potential showed a maximum in spring followed by a decline through the rainless summer and a recovery with autumn rainfall. Although the observed decrease in predawn leaf water potential in summer indicates soil water depletion, trees maintained transpiration rates above 0.7 mm day(-1) during the summer drought. By that time, more than 70% of the transpired water was being taken from groundwater sources. The daily fluctuations in soil water content suggest that some root uptake of groundwater was mediated through the upper soil layers by hydraulic lift. During the dry season, Q. ilex maintained higher predawn leaf water potentials, canopy conductances and transpiration rates than Q. suber. The higher water status of Q. ilex was likely associated with their deeper root systems compared with Q. suber. Whole-tree hydraulic conductance and minimum midday leaf water potential were lower in Q. ilex, indicating that Q. ilex was more tolerant to drought than Q. suber. Overall, Q. ilex seemed to have more effective drought avoidance and drought tolerance mechanisms than Q. suber.

Response of northern red oak, black walnut, and white ash seedlings to various levels of simulated summer deer browsing

Science.gov (United States)

Robert C. Morrissey; Douglass F. Jacobs; John R. Seifert

2008-01-01

Understanding the response of tree seedlings to browsing by white-tailed deer (Odocoileus virginianus Zimmerman) is critical to the management of high value hardwood plantations in the Central Hardwood Forest Region. One-year-old black walnut (Juglans nigra L.), northern red oak (Quercus rubra L.), and white ash...

Efficacy of Systemic Insecticides for Control of the Invasive Goldspotted Oak Borer (Coleoptera: Buprestidae) in California.

Science.gov (United States)

Coleman, Tom W; Smith, Sheri L; Jones, Michael I; Graves, Andrew D; Strom, Brian L

2017-10-01

From 2009 to 2013, we tested four systemic insecticide formulations and five application methods against the invasive goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), in California. The insecticides were evaluated in three experiments: 1) 2009 remedial applications of emamectin benzoate (stem-injection) and imidacloprid (stem-injection and soil-injection); 2) 2009-2012 emamectin benzoate and imidacloprid initially applied at different times during the dormant season with varying injection technologies; and 3) 2013 dinotefuran applied to several tree diameter size classes. Adult leaf-feeding bioassays were used to assess the impact of systemic treatments against A. auroguttatus, whereas enzyme-linked immunosorbent assays determined the quantity of the active ingredient of insecticide residues in foliage. Imidacloprid (experiment 1) persisted at elevated levels in foliage of coast live oak, Quercus agrifolia Née, for 1.5 yr following stem injections. Stem injections of emamectin benzoate (experiment 2) sometimes significantly decreased survival in adults fed foliage from treated Q. agrifolia, and both the emamectin benzoate and imidacloprid treatments reduced adult feeding in some trials. Imidacloprid residues in Q. agrifolia and California black oak, Quercus kelloggii Newb., foliage remained at elevated levels (>10 µg/g) ∼2 yr postapplication. In 2013 (experiment 3), dinotefuran residues were highest in foliage collections 2 wk postapplication and greatest in smaller diameter oaks, but insecticide treatment had no effect on survival or frass production by adults fed foliage from treated trees. Systemic injections of emamectin benzoate and imidacloprid applied during the dormant season to uninfested or lightly infested oaks can reduce adult A. auroguttatus survival and maturation feeding. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by (a) US Government employee

An evaluation of seven methods for controlling mountain laurel thickets in the mixed-oak forests of the central Appalachian Mountains, USA

Science.gov (United States)

Patrick H. Brose

2017-01-01

In the Appalachian Mountains of eastern North America, mountain laurel (Kalmia latifolia) thickets in mixed-oak (Quercus spp.) stands can lead to hazardous fuel situations, forest regeneration problems, and possible forest health concerns. Therefore, land managers need techniques to control mountain laurel thickets and limit...

Estudio cariológico de Quercus humboldtti Bonpl Caryological study of Quercus humboldtii Bonpl

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Alvarado de Coral Cecilia

1989-12-01

Full Text Available Se comprobó que la especie del roble Ouercus humboldtii Bonpl. tiene 2 n= 24 cromosomas, al igual que la mayoría de las especies estudiadas de Quercus. Utilizando pretratamiento y tinción con orceina lactopropiónica fue posible obtener el cariotipo e ideograma.Using lactopropionic orceine for a previus tintion we obtained the Caryotype and ideogram of Quercus humboldtii Bonpl. and we observed that it has 2 n = 24 chromosomes as most studied species of Quercus do.

Sap flow measurements combining sap-flux density radial profiles with punctual sap-flux density measurements in oak trees (Quercus ilex and Quercus pyrenaica) - water-use implications in a water-limited savanna-

Science.gov (United States)

Reyes, J. Leonardo; Lubczynski1, Maciek W.

2010-05-01

measurements using the HFD-measured radial profiles. The standard TDP daily mean of sap-flux density was 95% higher than the 2cm equivalent of the HFD for Q. ilex and 70% higher for Q. pyrenaica. NTG-corrected TDP daily mean of sap-flux density was 34% higher than HFD for Q. ilex and 47% lower for Q. pyrenaica. Regarding sap flow measurements, the standard TDP sap flow was 81% higher than HFD sap flow for Q. ilex and 297% for Q. pyrenaica. The NTG-corrected TDP sap flow was 24% higher than HFD sap flow for Q. ilex and 23% for Q. pyrenaica. The radial correction, for TDP-NTG-corrected sap-flux density, produced sap-flow measurements in well agreement with HFD, just slightly lower (-3% Q.i. and -4% Q.p.). The TDP-HFD sap flow data acquired in dry season over the savanna type of sparsely distributed oak trees (Q. ilex & Q. pyrenaica) showed that the TDP method must be corrected for NTG and for radial variability of sap flux density in trees with sapwood thicker than 2 cm. If such corrections are not taken into consideration, the amount of accounted water used by the trees is prone to overestimation, especially for Quercus pyrenaica. The obtained results indicate also that the combination of HFD and TDP leads to an efficient and accurate operational sap flow measurement schema that is currently in the optimization stage.

Stand-level growth and yield component models for red oak-sweetgum forests on Mid-South minor stream bottoms

Science.gov (United States)

Emily B. Schultz; J. Clint Iles; Thomas G. Matney; Andrew W. Ezell; James S. Meadows; Theodor D. Leininger; al. et.

2010-01-01

Greater emphasis is being placed on Southern bottomland hardwood management, but relatively few growth and yield prediction systems exist that are based on sufficient measurements. We present the aggregate stand-level expected yield and structural component equations for a red oak (Quercus section Lobatae)-sweetgum (Liquidambar styraciflua L.) growth and yield model....

Phylogeography of Quercus variabilis Based on Chloroplast DNA Sequence in East Asia : Multiple Glacial Refugia and Mainland-Migrated Island Populations

OpenAIRE

Chen, Dongmei; Zhang, Xianxian; Kang, Hongzhang; Sun, Xiao; Yin, Shan; Du, Hongmei; Yamanaka, Norikazu; Gapare, Washington; Wu, Harry X.; Liu, Chunjiang

2012-01-01

The biogeographical relationships between far-separated populations, in particular, those in the mainland and islands, remain unclear for widespread species in eastern Asia where the current distribution of plants was greatly influenced by the Quaternary climate. Deciduous Oriental oak (Quercus variabilis) is one of the most widely distributed species in eastern Asia. In this study, leaf material of 528 Q. variabilis trees from 50 populations across the whole distribution (Mainland China, Kor...

Improving the phytoremediation of heavy metals contaminated soil by use of sewage sludge

Science.gov (United States)

Placek, Agnieszka; Grobelak, Anna; Kacprzak, Malgorzata

2016-01-01

ABSTRACT Sewage sludge, in particular from the food industry, is characterized by fertilizing properties, due to the high content of organic matter and nutrients. The application of sewage sludge causes an improvement of soil parameters as well as increase in cation exchange capacity, and thus stronger binding of cations in the soil environment, which involves the immobilization of nutrients and greater resistance to contamination. In a field experiment sewage sludge has been used as an additive to the soil supporting the phytoremediation process of land contaminated with heavy metals (Cd, Zn, and Pb) using trees species: Scots pine (Pinus silvestris L.), Norway spruce (Picea abies L.), and oak (Quercus robur L.). The aim of the research was to determine how the application of sewage sludge into the soil surface improves the phytoremediation process. The conducted field experiment demonstrated that selected trees like Scots pine and Norway spruce, because of its excellent adaptability, can be used in the remediation of soil. Oak should not be used in the phytoremediation process of soils contaminated with high concentrations of trace elements in the soil, because a significant amount of heavy metals was accumulated in the leaves of oak causing a risk of recontamination. PMID:26368503

Oak Tree Canker Disease Supports Arthropod Diversity in a Natural Ecosystem

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Yong-Bok Lee

2014-03-01

Full Text Available Microorganisms have many roles in nature. They may act as decomposers that obtain nutrients from dead materials, while some are pathogens that cause diseases in animals, insects, and plants. Some are symbionts that enhance plant growth, such as arbuscular mycorrhizae and nitrogen fixation bacteria. However, roles of plant pathogens and diseases in natural ecosystems are still poorly understood. Thus, the current study addressed this deficiency by investigating possible roles of plant diseases in natural ecosystems, particularly, their positive effects on arthropod diversity. In this study, the model system was the oak tree (Quercus spp. and the canker disease caused by Annulohypoxylon truncatum, and its effects on arthropod diversity. The oak tree site contained 44 oak trees; 31 had canker disease symptoms while 13 were disease-free. A total of 370 individual arthropods were detected at the site during the survey period. The arthropods belonged to 25 species, 17 families, and seven orders. Interestingly, the cankered trees had significantly higher biodiversity and richness compared with the canker-free trees. This study clearly demonstrated that arthropod diversity was supported by the oak tree canker disease.

A comparative study of the chemical and integrated treatments impact against the defoliating insects on the structure and dynamics of the edaphic mesofauna in two oak forests from North-Eastern Romania

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Adina Cãlugãr

2009-11-01

Full Text Available The author presents in this paper some aspects about the edaphicmicroarthropods from the organic horizon of two forest soils belonging to the Ciurea Forest District, Iasi County: ªanta (mixed stands mainly with oak, chemically treated against defoliating insects and Poieni - Tomesti (Quercus robur and Quercuspetraea stands with integrated treatments. The study of edaphic microarthropods was performed both from qualitative and quantitative point of view. It considered the average of the total density of the microarthropod populations and by each taxonomic group, according to stations and subhorizons, as well as the ratio between thetaxonomical and trophic groups. The investigations concerning edaphic mesofauna consist in inventory and analysis of the mites belonging to Oribatida, Gamasida, Actinedida and Acaridida orders, of the Collembola, as well as other insects; other groups of microarthropods were taken into consideration too (pseudoscorpiones,myriapods etc. The consequences of the treatments against the defoliators on theedaphic mesofauna were performed at four different moments. Generally, lower densities were observed in the case of the chemically treated stands. The communities of the edaphic mesofauna from the integrated management treated stands are more stableduring the time. In the chemically treated stands, the densities of the microartropods vary between large limits; this instability could be assigned to this kind of treatment. The vertical distribution of the mesofauna depends on the textural characteristics of the soil, being at the same time a dynamic parameter that is modifyed according to the variation of the climatic factors.

Effects of ring-porous and diffuse-porous stem wood anatomy on the hydraulic parameters used in a water flow and storage model.

Science.gov (United States)

Steppe, Kathy; Lemeur, Raoul

2007-01-01

Calibration of a recently developed water flow and storage model based on experimental data for a young diffuse-porous beech tree (Fagus sylvatica L.) and a young ring-porous oak tree (Quercus robur L.) revealed that differences in stem wood anatomy between species strongly affect the calibrated values of the hydraulic model parameters. The hydraulic capacitance (C) of the stem storage tissue was higher in oak than in beech (939.8 versus 212.3 mg MPa(-1)). Model simulation of the elastic modulus (epsilon) revealed that this difference was linked to the higher elasticity of the stem storage tissue of oak compared with beech. Furthermore, the hydraulic resistance (R (x)) of beech was about twice that of oak (0.1829 versus 0.1072 MPa s mg(-1)). To determine the physiological meaning of the R (x) parameter identified by model calibration, we analyzed the stem wood anatomy of the beech and oak trees. Calculation of stem specific hydraulic conductivity (k (s)) of beech and oak with the Hagen-Poiseuille equation confirmed the differences in R (x) predicted by the model. The contributions of different vessel diameter classes to the total hydraulic conductivity of the xylem were calculated. As expected, the few big vessels contributed much more to total conductivity than the many small vessels. Compared with beech, the larger vessels of oak resulted in a higher k (s) (10.66 versus 4.90 kg m(-1) s(-1) MPa(-1)). The calculated ratio of k (s) of oak to beech was 2, confirming the R (x) ratio obtained by model calibration. Thus, validation of the R (x) parameter of the model led to identification of its physiological meaning.

Determination of Screw and Nail Withdrawal Resistance of Some Important Wood Species

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Alper Aytekin

2008-04-01

Full Text Available In this study, screw and nail withdrawal resistance of fir (Abies nordmanniana, oak (Quercus robur L. black pine (Pinus nigra Arnold and Stone pine (Pinus pinea L. wood were determined and compared. The data represent the testing of withdrawal resistance of three types of screws as smart, serrated and conventional and common nails. The specimens were prepared according to TS 6094 standards. The dimensions of the specimens were 5x5x15cm and for all of the directions. Moreover, the specimens were conditioned at ambient room temperature and 65±2% relative humidity. The screws and nails were installed according to ASTM-D 1761 standards. Nail dimensions were 2.5mm diameter and 50 mm length, conventional screws were 4x50mm, serrated screws were 4x45mm and smart screws were 4x50mm. Results show that the maximum screw withdrawal resistance value was found in Stone pine for the serrated screw. There were no significant differences between Stone pine and oak regarding screw withdrawal resistance values. Conventional screw yielded the maximum screw withdrawal resistance value in oak, followed by Stone pine, black pine and fir. Oak wood showed the maximum screw withdrawal resistance value for the smart screw, followed by Stone pine, black pine, and fir. Oak wood showed higher nail withdrawal resistances than softwood species. It was also determined that oak shows the maximum nail withdrawal resistance in all types. The nail withdrawal resistances at the longitudinal direction are lower with respect to radial and tangential directions.

Effects of Drought Stress and Ozone Exposure on Isoprene Emissions from Oak Seedlings in Texas

Science.gov (United States)

Madronich, M. B.; Harte, A.; Schade, G. W.

2014-12-01

Isoprene is the dominant hydrocarbon emitted by plants to the atmosphere with an approximate global emission of 550 Tg C yr-1. Isoprene emission studies have elucidated plants' isoprene production capacity, and the controlling factors of instantaneous emissions. However, it is not yet well understood how long-term climatic factors such as drought and increasing ozone concentrations affect isoprene emission rates. Drought reduces photosynthetic activity and is thus expected to reduce isoprene emission rate, since isoprene production relies on photosynthates. On the other hand, ozone is also known to negatively affect photosynthesis rates, but can instead increase isoprene emissions. These apparent inconsistencies and a lack of experimental data make it difficult to accurately parameterize isoprene emission responses to changing environmental conditions. The objective of this work is to reduce some of these uncertainties, using oak seedlings as a study system. Our project focuses on isoprene emission responses of oak trees to typical summer drought and high ozone conditions in Texas. We report on experiments conducted using a laboratory whole-plant chamber and leaf-level data obtained from greenhouse-grown seedlings. The chamber experiment studied the effects of ozone and drought on isoprene emissions from >3 year old oak seedlings under controlled conditions of photosynthetically active radiation (PAR), temperature, soil-moisture and the chamber's air composition. Stress in plants was induced by manipulating potted soil-moisture and ozone concentration in the chamber. The greenhouse study focused on understanding the effects of drought under Texas climatic conditions. For this study we used two year old seedlings of water oak (Quercus nigra) and post oak (Quercus stellata). Temperature, humidity and light in the greenhouse followed local conditions. Leaf-level conductance, photosynthesis measurements and isoprene sampling were carried out under controlled leaf

Molecular and morphological characterization of Xiphinema chambersi population from live oak in Jekyll Island, Georgia, with comments on morphometric variations

Science.gov (United States)

Zafar A Handoo; Lynn K. Carta; Andrea M. Skantar; Sergei A. Subbotin; Stephen W. Fraedrich

2016-01-01

A population of Xiphinema chambersi from the root zone around live oak (Quercus virginiana Mill.) trees on Jekyll Island, GA, is described using both morphological and molecular tools and compared with descriptions of type specimens. Initially, because of a few morphological differences, this nematode was thought to represent...

Use of Nested and Real-Time PCR for the Detection of Ceratocystis fagacearum in the Sapwood of Diseased Oak Species in Minnesota

Science.gov (United States)

A. Yang; J. Juzwik

2017-01-01

Oak wilt caused by Ceratocystis fagacearum is a significant disease of Quercus spp. in the eastern United States. Early and accurate detection of the pathogen is particularly important when disease control is planned. Nested and real-time polymerase chain reaction (PCR) methods utilizing fungal DNA extracted from sapwood drill...

Evaluating small mammal response to natural disturbance and restoration in oak ecosystems in the Mississippi alluvial valley

International Nuclear Information System (INIS)

Smith Carl G; Hamel Paul B; Fuzaro Gullo, Manoelle

2010-01-01

Oak species form a conspicuous and often dominant component of bottom land forests of the Mississippi Alluvial Valley. The extent of these forests has been drastically reduced as a result of clearing for agriculture in the past two centuries. Patterns of clearing have reduced the distribution of remaining forest patches to a much more flood-prone subset of the landscape than was historically the case, reducing the diversity of oak species currently present on the landscape. Intensive harvesting has further changed the composition of the remaining stands. Small remnant patches of primary forest continue to exist as Research Natural Areas on the Delta National Forest in Sharkey County, Mississippi. In particular, the Over cup Oak (Quercus lyrata) and Redgum (Liquidambar styraciflua) Research Natural Areas pres ent substantial components of the trees for which the areas were named, as well as Quercus nuttallii and smaller components of other species. Recent interest in afforestation has produced a resurgence of interest in restoration of oak forest to abandoned farmland in the region. We have studied small mammal response to restoration on an extensive experiment near the Delta National Forest since 1995. We have also examined small mammal response to a tornado that disturbed approximately half of the Over cup Oak Research Natural Area in 2008. We use these studies to demonstrate how population estimates of small mammals can be obtained from capture-recapture studies, employing different designs, and utilizing Program Capture for population estimation. Small mammal communities in these stands are more species-rich in early succession than in primary forest. The study of response to tornado damage to the Over cup Oak Research Natural Area is complicated by the fact that this particular forest type is very flood-prone, creating obstacles to colonization by small mammals. Analysis of capture-recapture data with robust methods illustrated in this study permits extraction

Increase of radiocarbon concentration in tree rings from Kujawy (SE Poland) around AD 774–775

International Nuclear Information System (INIS)

Rakowski, Andrzej Z.; Krąpiec, Marek; Huels, Mathias; Pawlyta, Jacek; Dreves, Alexander; Meadows, John

2015-01-01

Evidence of a rapid increase in atmospheric radiocarbon ( 14 C) content in AD 774–775 was presented by Miyake et al. (2012), who observed an increase of about 12‰ in the 14 C content in annual tree rings from Japanese cedar. Usoskin et al. (2013) report a similar 14 C spike in German oak, and attribute it to exceptional solar activity. If this phenomenon is global in character, such rapid changes in 14 C concentration may affect the accuracy of calibrated dates, as the existing calibration curve is composed mainly of decadal samples. Single-year samples of dendro-chronologically dated tree rings of deciduous oak (Quercus robur) from Kujawy, a village near Krakow (SE Poland), spanning the years AD 765–796, were collected and their 14 C content was measured using the AMS system in the Leibniz Laboratory. The results clearly show a rapid increase of 9.2 ± 2.1‰ in the 14 C concentration in tree rings between AD 774 and AD 775, with maximum Δ 14 C = 4.1 ± 2.3‰ noted in AD 776.

Increase of radiocarbon concentration in tree rings from Kujawy (SE Poland) around AD 774–775

Energy Technology Data Exchange (ETDEWEB)

Rakowski, Andrzej Z., E-mail: arakowski@polsl.pl [Leibniz-Laboratory for Radiometric Dating and Isotope Research, University Kiel, Max-Eyth-Str. 11-13, 24118 Kiel (Germany); Institute of Physics – Center for Science and Education, Silesian University of Technology, Konarskiego Str. 22B, 44-100 Gliwice (Poland); Krąpiec, Marek [AGH University of Science and Technology, Mickiewicza Av. 30, 30-059 Krakow (Poland); Huels, Mathias [Leibniz-Laboratory for Radiometric Dating and Isotope Research, University Kiel, Max-Eyth-Str. 11-13, 24118 Kiel (Germany); Pawlyta, Jacek [Institute of Physics – Center for Science and Education, Silesian University of Technology, Konarskiego Str. 22B, 44-100 Gliwice (Poland); Dreves, Alexander [Leibniz-Laboratory for Radiometric Dating and Isotope Research, University Kiel, Max-Eyth-Str. 11-13, 24118 Kiel (Germany); Meadows, John [Leibniz-Laboratory for Radiometric Dating and Isotope Research, University Kiel, Max-Eyth-Str. 11-13, 24118 Kiel (Germany); Centre for Baltic and Scandinavian Archaeology, Schleswig-Holstein State Museums Foundation, Schloss Gottorf, Schloßinsel, 24837 Schleswig (Germany)

2015-10-15

Evidence of a rapid increase in atmospheric radiocarbon ({sup 14}C) content in AD 774–775 was presented by Miyake et al. (2012), who observed an increase of about 12‰ in the {sup 14}C content in annual tree rings from Japanese cedar. Usoskin et al. (2013) report a similar {sup 14}C spike in German oak, and attribute it to exceptional solar activity. If this phenomenon is global in character, such rapid changes in {sup 14}C concentration may affect the accuracy of calibrated dates, as the existing calibration curve is composed mainly of decadal samples. Single-year samples of dendro-chronologically dated tree rings of deciduous oak (Quercus robur) from Kujawy, a village near Krakow (SE Poland), spanning the years AD 765–796, were collected and their {sup 14}C content was measured using the AMS system in the Leibniz Laboratory. The results clearly show a rapid increase of 9.2 ± 2.1‰ in the {sup 14}C concentration in tree rings between AD 774 and AD 775, with maximum Δ{sup 14}C = 4.1 ± 2.3‰ noted in AD 776.

Dry deposition of sulfate to Quercus rubra and Liriodendron tulipifera foliage

International Nuclear Information System (INIS)

Vandenberg, J.J.

1987-01-01

Estimates were made of the rate of dry deposition to red oak (Quercus rubra) and tulip poplar (Liriodendron tulipifera) foliage. In the laboratory, radioactive ammonium sulfate aerosols were generated in an exposure chamber. These aerosols were dry deposited onto leaves that were sequentially washed to examine the efficacy of washing procedures in removal of surface deposits. Over 90% of dry deposited sulfate was removed after a 30 second wash duration. Laboratory procedures also estimated the magnitude of foliar sulfur that leached into leaf wash solutions. The majority of laboratory leaves demonstrated no leaching of sulfur from the internal pool. However, some leaves showed significant sulfur leaching. It was concluded that leaching of internal sulfur was highly leaf specific. This indicated that each leaf used in field experiments needed to be individually examined for leaching

Molecular and morphological characterization of Xiphinema chambersi population from live oak in Jekyll Island, Georgia, with comments on morphometric variations

Science.gov (United States)

Zafar A. Handoo; Lynn K. Carta; Andrea M. Skantar; Sergei A. Subbotin; Stephen Fraedrich

2016-01-01

A population of Xiphinema chambersi from the root zone around live oak (Quercus virginiana Mill.) trees on Jekyll Island, GA, is described using both morphological and molecular tools and compared with descriptions of type specimens. Initially, because of a few morphological differences, this nematode was thought to represent an undescribed species. However, on further...

Endangered Species Management Plan for Fort Hood, Texas: FY06-10

Science.gov (United States)

2007-05-01

Texas red oak, post oak, Texas ash (Fraxinus texensis), shin oak, blackjack oak (Quercus marilandica), slippery elm (Ulmus rubra), cedar elm ...by Ashe juniper and Texas oak. Other important tree species included live oak, cedar elm (Ulmus crassifolia), Lacey oak (Quercus laceyi), Arizona...0.83 m (Cimprich 2005). Nest substrates include shin oak, Texas red oak, Texas redbud, Ashe juniper, Texas ash, Plateau live oak, cedar elm , rusty

Partitioning of current photosynthate to different chemical fractions in leaves, stems, and roots of northern red oak seedlings during episodic growth

Science.gov (United States)

Richard E. Dickson; Patricia T. Tomlinson; J. G. Isebrands

2000-01-01

The episodic or flushing growth habit of northern red oak (Quercus rubra L.,) has a significant influence on carbon fixation, carbon transport from source leaves, and carbon allocation within the plant; however, the impact of episodic growth on carbon parciprioning among chemical fractions is unknown. Median-flush leaves of the first and second flush...

The negative impact of intentionally introduced Quercus rubra L. on a forest community

Directory of Open Access Journals (Sweden)

Beata Woziwoda

2014-03-01

Full Text Available Some alien woody species used in commercial forestry become invasive and, as invaders, cause major problems in natural and semi-natural ecosystems. However, the deliberate introduction of aliens can bring unintended negative changes also within areas of their cultivation. This paper presents the effects of the intentional introduction of the North-American Quercus rubra in European mixed Scots pine-Pedunculate oak forests (POFs: Querco roboris-Pinetum (W. Mat. 1981 J. Mat. 1988. Phytosociological data from field research combined with GIS data analysis of the current distribution of Northern Red oak in the studied habitat were used to determine the composition and structure of forest communities in plots with and without Q. rubra participation.  The results show that Q. rubra significantly reduces native species richness and abundance, both in old-growth and in secondary (post-agricultural forests. Not one resident vascular plant benefits from the introduction of Northern Red oak and only a few are able to tolerate its co-occurrence. The natural restocking of all native woody species is also strongly limited by this alien tree.  The introduction of Northern Red oak significantly limits the environmental functions of the POF ecosystem and weakens its economic and social aspects. However, its further cultivation is justified from an economic point of view, as the essential function of the studied forests is commercial timber production, and the introduction of this fast growing alien tree supports the provisioning ecosystem services. A clear description of the level of trade-off between the accepted negative and positive effects of the introduction of Q. rubra on forest ecosystem services requires further interdisciplinary studies.

Oak Bark Allometry and Fire Survival Strategies in the Chihuahuan Desert Sky Islands, Texas, USA

OpenAIRE

Schwilk, Dylan W.; Gaetani, Maria S.; Poulos, Helen M.

2013-01-01

Trees may survive fire through persistence of above or below ground structures. Investment in bark aids in above-ground survival while investment in carbohydrate storage aids in recovery through resprouting and is especially important following above-ground tissue loss. We investigated bark allocation and carbohydrate investment in eight common oak (Quercus) species of Sky Island mountain ranges in west Texas. We hypothesized that relative investment in bark and carbohydrates changes with tre...

Impacts of elevated atmospheric CO2 on litter quality, litter decomposability and nitrogen turnover rate of two oak species in a Mediterranean forest ecosystem

NARCIS (Netherlands)

Fayez Raiesi Gahrooee,

1998-01-01

Elevated CO2 may affect litter quality of plants, and subsequently C and N cycling in terrestrial ecosystems, but changes in litter quality associated with elevated CO2 are poorly known. Abscised leaf litter of two oak species (Quercus cerris L., and Q. pubescens Willd.) exposed to long-term

Characterization of Quercus species distributed in Jordan using ...

African Journals Online (AJOL)

User

2013-03-20

Mar 20, 2013 ... improving conservation, restoration and reforestation strategies of Quercus in Jordan. Key words: Quercus spp., genetic ..... High variation leads to develop- ment of subspecies and varieties (Zohary, 1962). .... genetic diversity and differentiation of Quercus crispula in the. Chichibu Mountains, central Japan.

A method to quantify infection and colonization of holm oak (Quercus ilex roots by Phytophthora cinnamomi

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Ruiz-Gómez Francisco J

2012-09-01

Full Text Available Abstract Phytophthora cinnamomi Rands. is an important root rot pathogen widely distributed in the north hemisphere, with a large host range. Among others diseases, it is known to be a principal factor in the decline of holm oak and cork oak, the most important tree species in the “dehesa” ecosystem of south-western Spain. Previously, the focus of studies on P. cinnamomi and holm oak have been on molecular tools for identification, functional responses of the host, together with other physiological and morphological host variables. However, a microscopic index to describe the degree of infection and colonization in the plant tissues has not yet been developed. A colonization or infection index would be a useful tool for studies that examine differences between individuals subjected to different treatments or to individuals belonging to different breeding accessions, together with their specific responses to the pathogen. This work presents a methodology based on the capture and digital treatment of microscopic images, using simple and accessible software, together with a range of variables that quantify the infection and colonization process.

El ciclo del potasio en dehesas de Quercus rotundifolia y Quercus pyrenaica

OpenAIRE

Escudero Berián, Alfonso; García Criado, Balbino; Alonso Peloche, Herminio

1985-01-01

Hemos estudiado el ciclo del potasio en dehesas de Quercus rotundifolia Lam. y Quercus pyrenaica Willd. de la provincia de Salamanca. El potasio es el elemento que se transfiere en mayores proporciones a través de frutos y de material herbáceo, que son materias altamente digestibles. Por ello, su transferencia al subsistema herbívoro es mayor que para los restantes nutrientes. El potasio es también el macronutriente más intensamente extraído de los tejidos vegetables por el ...

Characterization of Quercus species distributed in Jordan using ...

African Journals Online (AJOL)

User

2013-03-20

Mar 20, 2013 ... improving conservation, restoration and reforestation strategies of Quercus in Jordan. Key words: Quercus spp., genetic ... ciation of the Mediterranean sclerophyllous broad-leaf forests (Schiller et al., 2004a). ..... genetic diversity and differentiation of Quercus crispula in the. Chichibu Mountains, central ...

Tree species effect on the redistribution of soil metals

NARCIS (Netherlands)

Mertens, J.; Nevel, Van L.; Schrijver, De A.; Piesschaert, F.; Oosterbaan, A.; Tack, F.M.G.; Verheyen, K.

2007-01-01

Phytostabilization of metals using trees is often promoted although the influence of different tree species on the mobilization of metals is not yet clear. Soil and biomass were sampled 33 years after planting four tree species (Quercus robur, Fraxinus excelsior, Acer pseudoplatanus, Populus

Ecological anachronisms in the recruitment of temperate light-demanding tree species in wooded pastures

NARCIS (Netherlands)

Bakker, ES; Olff, H; Vandenberghe, C; De Maeyer, K; Smit, R; Gleichman, JM; Vera, FWM

1. Light-demanding trees and thorny shrubs in temperate plant communities may reflect adaptations to now-extinct large grazers, such as aurochs and tarpans, rendering these adaptations ecological anachronisms. 2. We explored the ecological functions of plant traits of Quercus robur and Prunus

Análisis de la capacidad de acumulación de agua de diferentes especies de hojarasca en relación con la intercepción arbórea.

OpenAIRE

Sancho Bombin, Garbiñe

2013-01-01

En el presente estudio se aborda la problemática de la capacidad de acumulación de agua de hojarasca de 4 especies arbóreas (Quercus robur, Fagus sylvatica, Pinus radiata y Pinus sylvestris). Se realizaron experimentos en el laboratorio de mojado y secado de la hojarasca para determinar su capacidad máxima de retención de agua. Así como experimentos de campo en los que se colocaron las muestras bajo copas de diferentes árboles (P.radiata y Q.robur) y en claros para determinar el efecto de ...

Chemical investigation on wood tree species in a temperate forest, east-northern Romania

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Teaca, C. A.

2007-02-01

Full Text Available A quantitative evaluation of wood chemical components for some tree species in a forest area from east-northern Romania is presented here, through a comparative study from 1964 to 2000. Investigation upon the wood tree-rings in a Quercus robur L. tree species, as a dominant species, as regards its chemical composition and structure of the natural polymer constituents - cellulose and lignin - was also performed through chemical methods to separate the main wood components, FT-IR spectroscopy, and thermogravimetry. Having in view the impact of climate and external factors (such as pollutant depositions, some possible correlations between wood chemical composition and its further use can be made. The FT-IR spectra give evidence of differences in the frequency domains of 3400-2900 cm-1 and 1730-1640 cm-1, due to some interactions between the chemical groups (OH, C=O. The crystallinity index of cellulose presents variations in the oak wood tree-rings. Thermogravimetry analyses show different behaviour of cellulose at thermal decomposition, as a function of radial growth and tree’s height. A preliminary chemical investigation of oak wood sawdust shows a relatively high content of mineral elements (ash, compared with a previous study performed in 1964, fact that may indicate an intense drying process of the oak tree, a general phenomenon present in European forests for this species.

Final Environmental Assessment of Military Housing Privatization Barksdale Air Force Base, Louisiana

Science.gov (United States)

2006-01-01

loblolly pine (Pinus taeda), pecan ( Carya illinoensis ), sweetgum (Liquidambar styraciflua), water oak (Quercus nigra), red oak (Quercus sp...blackjack oak (Q. marilandica), mockernut hickory ( Carya tomentosa), pignut hickory (C. glabra), blackgum (Nyssa sylvatica), winged elm (Ulmus alata

Environmental Impact Assessment Sandia Laboratories, New Mexico.

Science.gov (United States)

1977-05-01

awn (Aristida divaricata) 45. Arizona three-awn (Aristida arizonica ) 46. Purple three-awn (Aristida purpurea) 47. Wright’s three-awn (Aristida wrightii...californica) Willow Family *102. Fremont cottonwood (Populus fremontii) Beech Family *103. Gambel oak ( Quercus gambelii) *104. Gray oak ( Quercus grisea...105. Shrub live oak ( Quercus turbinella) Elm Family *106. Siberian elm or Chinese elm (Ulmus pumila) 107. Netlead hackberry (Celtis reticulata) Nist

The Role of Tree Mortality in Vitality Assessment of Sessile Oak Forests

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Imre Berki

2016-12-01

Full Text Available Background and Purpose: The drought-induced vitality loss of sessile oak (Quercus petraea (Matt. Liebl. has been continuously observed in Hungary for more than three decades. The decrease in stand density as a consequence of drought-induced mortality has not been taken into consideration in most of the monitoring methods. Materials and Methods: Forest stands without any forest intervention during the last 30 years were selected. Quadrats were designated for the analysis in 18 sessile oak stands along a climatic transect in which foliage transparency and stand density were measured. Drought stress was defined by the water balance approach. By combining the foliage transparency and the relative stand density, a new cumulative assessment method of stand level vitality was introduced to get a more realistic picture about the effects of long-term drought (lasting for several decades on the sessile oak forests in South-East Europe. Results: The calculated health status (100% - vital; 0% - dead of the sessile oak stands was between 70-90% in the moist South-West Hungary and below 50% close to its xeric limit. The individual tree-based vitality assessment method gave considerably higher values on 17 out of 18 sites. Conclusions: Forest monitoring should also consider stand level-based tree mortality in oak forests while assessing health condition especially close to its xeric limit. The proposed new method provides a more realistic picture about the effects of climate change on sessile oak stands particularly for forest managers interested in changing in the wood stock of forests.

Changes in understory species occurrence of a secondary broadleaved forest after mass mortality of oak trees under deer foraging pressure

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Hiroki Itô

2016-12-01

Full Text Available The epidemic of mass mortality of oak trees by Japanese oak wilt has affected secondary deciduous broadleaved forests that have been used as coppices in Japan. The dieback of oak trees formed gaps in the crown that would be expected to enhance the regeneration of shade-intolerant pioneer species. However, foraging by sika deer Cervus nippon has also affected forest vegetation, and the compound effects of both on forest regeneration should be considered when they simultaneously occur. A field study was conducted in Kyôto City, Japan to investigate how these compound effects affected the vegetation of the understory layer of these forests. The presence/absence of seedlings and saplings was observed for 200 quadrats sized 5 m ×5 m for each species in 1992, before the mass mortality and deer encroachment, and in 2014 after these effects. A hierarchical Bayesian model was constructed to explain the occurrence, survival, and colonization of each species with their responses to the gaps that were created, expanded, or affected by the mass mortality of Quercus serrata trees. The species that occurred most frequently in 1992, Eurya japonica, Quercus glauca, and Cleyera japonica, also had the highest survival probabilities. Deer-unpalatable species such as Symplocos prunifolia and Triadica sebifera had higher colonization rates in the gaps, while the deer-palatable species Aucuba japonica had the smallest survival probability. The gaps thus promoted the colonization of deer-unpalatable plant species such as Symplocos prunifolia and Triadica sebifera. In the future, such deer-unpalatable species may dominate gaps that were created, expanded, or affected by the mass mortality of oak trees.

Land change in eastern Mediterranean wood-pasture landscapes: the case of deciduous oak woodlands in Lesvos (Greece).

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Schaich, Harald; Kizos, Thanasis; Schneider, Stefan; Plieninger, Tobias

2015-07-01

In Mediterranean Europe, wood-pasture landscapes with oak woodlands as emblematic ecosystems are undergoing rapid land-use change, which may threaten their legacy as hotspots of biodiversity, ecosystem services, and cultural heritage. The objective of this study was to quantify land cover changes and transitions as well as the dynamics of oak woodland patterns and densities over 50 years in two municipalities at the center and edges of Quercus macrolepis distribution in Northern Lesvos (Greece). We used aerial photographs from 1960 and WorldView-2 satellite images from 2010 to process land cover maps and metrics, and to calculate oak canopy cover with a point-grid sampling approach. Spatiotemporal dynamics of land cover change were generally high--especially between oak woodlands and grass- and shrub-lands, resulting in a more heterogeneous and fragmented landscape in 2010. Surprisingly, oak woodland area remained stable with marginal losses in one study site and gains in the other one. Oak canopy cover increased by 8 and 9%. Spatial hotspots of change were mountainous and peripheral phrygana areas with expanding oak stands, as well as river valleys and near urban areas with expanding olive groves and grass- and shrublands in former complex cultivation and oak stands. We conclude that the parallel processes of abandonment of crop cultivation and intensification of livestock grazing have been less detrimental to oak woodlands than supposed. To ensure long-term persistence of oak woodlands in the face of ongoing rural depopulation and land-use intensification, environmental and agricultural policies should better address their specificities as anthropogenic habitats.

Land Change in Eastern Mediterranean Wood-Pasture Landscapes: The Case of Deciduous Oak Woodlands in Lesvos (Greece)

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Schaich, Harald; Kizos, Thanasis; Schneider, Stefan; Plieninger, Tobias

2015-07-01

In Mediterranean Europe, wood-pasture landscapes with oak woodlands as emblematic ecosystems are undergoing rapid land-use change, which may threaten their legacy as hotspots of biodiversity, ecosystem services, and cultural heritage. The objective of this study was to quantify land cover changes and transitions as well as the dynamics of oak woodland patterns and densities over 50 years in two municipalities at the center and edges of Quercus macrolepis distribution in Northern Lesvos (Greece). We used aerial photographs from 1960 and WorldView-2 satellite images from 2010 to process land cover maps and metrics, and to calculate oak canopy cover with a point-grid sampling approach. Spatiotemporal dynamics of land cover change were generally high—especially between oak woodlands and grass- and shrub-lands, resulting in a more heterogeneous and fragmented landscape in 2010. Surprisingly, oak woodland area remained stable with marginal losses in one study site and gains in the other one. Oak canopy cover increased by 8 and 9 %. Spatial hotspots of change were mountainous and peripheral phrygana areas with expanding oak stands, as well as river valleys and near urban areas with expanding olive groves and grass- and shrublands in former complex cultivation and oak stands. We conclude that the parallel processes of abandonment of crop cultivation and intensification of livestock grazing have been less detrimental to oak woodlands than supposed. To ensure long-term persistence of oak woodlands in the face of ongoing rural depopulation and land-use intensification, environmental and agricultural policies should better address their specificities as anthropogenic habitats.

Phytosociological studies of the forests with sessile oak and Norway spruce from South-Eastern Transylvania

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Adrian Indreica

2011-02-01

Full Text Available The forests with sessile oak (Quercus petraea and Norway spruce (Picea abies from south-eastern Transylvania represent a peculiar type of phytocenoses, rather unusual for the present-day vegetation of Romania’s territory. Aim of the study is to provide a detailed description of the vegetation and to identify the phytosociological and typological units to which it could belong. Beside this, stand structure and regeneration status of the main tree species are illustrated. The studied area is located around Carpathian intermountain depressions Braşov and Ciuc, where vegetation had a peculiar history and today sessile oak forests on high altitude exists, interfering with spruce forests. The hypothesis of the process naturalness is supported by vegetation history in the area, climate, stand structure and peculiarities of herb layer composition (the mixture of relic of both mountain-boreal origin and south-European origin, like Vaccinium vitis-idaea, Pyrola rotundifolia and respectively Potentilla micrantha, Lathyrus venetus respectively. Sintaxonomically, studied phytocenoses with sessile oak and spruce belong mainly to acidophilus oak forests (Luzulo luzuloidis-Quercetum petraeae, but some of them resemble oak-hornbeam forests (Carici pilosae-Carpinetum, indicating a more recent change in stand structure and suggesting that not the soil, but the climate is the driving force of succession. Regeneration of sessile oak is at least satisfactory, but the expansion of spruce in such stands could seriously restrict the survival of sessile oak. A new typological unit will be appropriate,for a better management of sessile oak forests with spruce admixture.

Phytosociological studies of the forests with sessile oak and Norway spruce from South-Eastern Transylvania

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Adrian Indreica

2011-06-01

Full Text Available The forests with sessile oak (Quercus petraea and Norway spruce (Picea abies from south-eastern Transylvania represent a peculiar type of phytocenoses, rather unusual for the present-day vegetation of Romania’s territory. Aim of the study is to provide a detailed description of the vegetation and to identify the phytosociological and typological units to which it could belong. Beside this, stand structure and regeneration status of the main tree species are illustrated. The studied area is located around Carpathian intermountain depressions Brasov and Ciuc, where vegetation had a peculiar history and today sessile oak forests on high altitude exists, interfering with spruce forests. The hypothesis of the process naturalness is supported by vegetation history in the area, climate, stand structure and peculiarities of herb layer composition (the mixture of relic of both mountain-boreal origin and south-European origin, like Vaccinium vitis-idaea, Pyrola rotundifolia and respectively Potentilla micrantha, Lathyrus venetus respectively. Sintaxonomically, studied phytocenoses with sessile oak and spruce belong mainly to acidophilus oak forests (Luzulo luzuloidis-Quercetum petraeae, but some of them resemble oak-hornbeam forests (Carici pilosae-Carpinetum, indicating a more recent change in stand structure and suggesting that not the soil, but the climate is the driving force of succession. Regeneration of sessile oak is at least satisfactory, but the expansion of spruce in such stands could seriously restrict the survival of sessile oak. A new typological unit will be appropriate, for a better management of sessile oak forests with spruce admixture.

Effects of sulfur dioxide on conifers

Energy Technology Data Exchange (ETDEWEB)

Govi, G.; Tagliani, F.; Cimino, A.

1974-01-01

Trials on the resistance of several conifer and oak species to the effects of sulfur dioxide at different concentrations and moisture levels were conducted. 72 combinations were experimented. The damages began to appear under the following conditions: Abies alba: 0.3 ppm, 25/sup 0/C, 70% ur after 24 hours; Picea excelsa: 0.3 ppm, 15/sup 0/C, 70-95% ur after 24 hours; Cedrus deodara: 0.3 ppm, 15/sup 0/C, 95% ur after 48 hours; Pinus pinea: 0.3 ppm, 15/sup 0/C, 70-95% after 72 hours; Pinus strobus 0.3 ppm, 25/sup 0/C, 70-95%, after 48 hours; Pinus pinaster: similar to the former; Pinus nigra: 2 ppm, 25/sup 0/C, 70-95%, ur after 5 days; Cupressus arizonica and C. semperivirens: 2 ppm, 25%/sup 0/C, 90% ur after 72 hours; Quercus robur: 5 ppm, 25/sup 0/C, 90% ur, after 10 days. 6 references, 3 figures, 1 table.

Response of two populations of holm oak (Quercus rotundifolia Lam.) to sulfur dioxide.

Science.gov (United States)

García, D; Rodríguez, J; Sanz, J M; Merino, J

1998-01-01

Experiments were carried out with seedlings of Quercus rotundifolia Lam., an evergreen schlerophyllous tree typical of the Spanish Mediterranean climate environments. Fruits were collected in two distant (800 km) populations located in the center (southern Spain) and northern border (northern Spain) of the area of distribution of the species. One-month-old potted plants were grown for 130 days in an enriched atmosphere of SO2 (0.23 ppm, 14 h/day) in controlled (growth chamber) conditions. Both northern and southern plants underwent a significant decrease in growth rate as a consequence of the treatment. Even so, plants appear to be quite resistant to SO2 compared with either more temperate or more productive species. The southern population was more sensitive to the treatment, as reflected by the bigger decrease in both growth and photosynthetic rates. Differences in resistance appear to be related to the biogeographic origin of the populations studied, which underlines the importance of biogeographic aspects in studies of resistance to air pollutants.

Drivers of radial growth and carbon isotope discrimination of bur oak (Quercus macrocarpa Michx.) across continental gradients in precipitation, vapour pressure deficit and irradiance.

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Voelker, Steven L; Meinzer, Frederick C; Lachenbruch, Barbara; Brooks, J Renée; Guyette, Richard P

2014-03-01

Tree-ring characteristics are commonly used to reconstruct climate variables, but divergence from the assumption of a single biophysical control may reduce the accuracy of these reconstructions. Here, we present data from bur oaks (Quercus macrocarpa Michx.) sampled within and beyond the current species bioclimatic envelope to identify the primary environmental controls on ring-width indices (RWIs) and carbon stable isotope discrimination (Δ(13) C) in tree-ring cellulose. Variation in Δ(13) C and RWI was more strongly related to leaf-to-air vapour pressure deficit (VPD) at the centre and western edge of the range compared with the northern and wettest regions. Among regions, Δ(13) C of tree-ring cellulose was closely predicted by VPD and light responses of canopy-level Δ(13) C estimated using a model driven by eddy flux and meteorological measurements (R(2)  = 0.96, P = 0.003). RWI and Δ(13) C were positively correlated in the drier regions, while they were negatively correlated in the wettest region. The strength and direction of the correlations scaled with regional VPD or the ratio of precipitation to evapotranspiration. Therefore, the correlation strength between RWI and Δ(13) C may be used to infer past wetness or aridity from paleo wood by determining the degree to which carbon gain and growth have been more limited by moisture or light. © 2013 John Wiley & Sons Ltd.

Overstory density affects field performance of underplanted red oak (Quercus rubra L.) in Ontario

Science.gov (United States)

Daniel C. Dey; William C. Parker

1997-01-01

Red oak seedlings were underplanted in a closed-canopy mature northern hardwood stand and an adjacent shelterwood in central Ontario. Overstory density effects on seedling survival and growth were assessed 2 yr after planting. After 2 yr, seedling survival was 90% in the uncut stand and over 99% in the shelterwood. Seedlings in the uncut stand experienced negligible or...

Assessing the Cost of an Invasive Forest Pathogen: A Case Study with Oak Wilt

Science.gov (United States)

Haight, Robert G.; Homans, Frances R.; Horie, Tetsuya; Mehta, Shefali V.; Smith, David J.; Venette, Robert C.

2011-03-01

Economic assessment of damage caused by invasive alien species provides useful information to consider when determining whether management programs should be established, modified, or discontinued. We estimate the baseline economic damage from an invasive alien pathogen, Ceratocystis fagacearum, a fungus that causes oak wilt, which is a significant disease of oaks ( Quercus spp.) in the central United States. We focus on Anoka County, Minnesota, a 1,156 km2 mostly urban county in the Minneapolis-Saint Paul metropolitan region. We develop a landscape-level model of oak wilt spread that accounts for underground and overland pathogen transmission. We predict the economic damage of tree mortality from oak wilt spread in the absence of management during the period 2007-2016. Our metric of economic damage is removal cost, which is one component of the total economic loss from tree mortality. We estimate that Anoka County has 5.92 million oak trees and 885 active oak wilt pockets covering 5.47 km2 in 2007. The likelihood that landowners remove infected oaks varies by land use and ranges from 86% on developed land to 57% on forest land. Over the next decade, depending on the rates of oak wilt pocket establishment and expansion, 76-266 thousand trees will be infected with discounted removal cost of 18-60 million. Although our predictions of removal costs are substantial, they are lower bounds on the total economic loss from tree mortality because we do not estimate economic losses from reduced services and increased hazards. Our predictions suggest that there are significant economic benefits, in terms of damage reduction, from preventing new pocket establishment or slowing the radial growth of existing pockets.

Chromatographic analysis of natural pigments L. and quercus infectoria oliv: produced from datisca cannabina plants and their antimicrobial activity

International Nuclear Information System (INIS)

Deveoglu, O.; Muhammed, A.; Fouad, A.; Torgan, E.; Karadag, R.

2012-01-01

In this study, natural pigments from the hemp (Datisca cannabina L.) and dyer's oak ). 12H/sub 2/O (alum) mordant. A (Quercus infectoria Oliv.) dye plants were prepared by using KAl(SO/sub 4)/sub 2/ reversed-phase high performance liquid chromatography (RP-HPLC) with diode array detection (DAD) method was used in the identification of dyes in the natural pigments. The dye extractions from the natural pigments were carried out with 37% HCl/MeOH/H/sub 2/O (2:1:1 v/v/v) mixture. Also, antimicrobial activity of crude extracts of plants and pigments were investigated. (author)

Experimental minimum threshold for Phytophthora cinnamomi root disease expression on Quercus suber

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María Socorro SERRANO

2015-12-01

Full Text Available Quercus suber seedlings were potted in soils infested with increasing concentrations of Phytophthora cinnamomi chlamydospores and submitted to weekly flooding for 3 months to favour root infections. Increasing quantities of chlamydospores led to an exponential increase in their ability to germinate. Root symptoms (necrosis and/or absence of feeder roots were significantly more severe than those recorded in uninfested soil only for plants potted in soils infested with 61 cfu g-1 or more. Although generated using potting mix, this minimum threshold represents a tool for checking the potential infectivity of infested soils or to assess the effectiveness of some control methods to reduce soil inoculum. However, a low level of root infection was recorded even at 3 cfu g-1. Therefore, long-term disease risk may be present whenever the pathogen is detectable in oak forest soils.

Predicting the economic costs and property value losses attributed to sudden oak death damage in California (2010-2020).

Science.gov (United States)

Kovacs, Kent; Václavík, Tomáš; Haight, Robert G; Pang, Arwin; Cunniffe, Nik J; Gilligan, Christopher A; Meentemeyer, Ross K

2011-04-01

Phytophthora ramorum, cause of sudden oak death, is a quarantined, non-native, invasive forest pathogen resulting in substantial mortality in coastal live oak (Quercus agrifolia) and several other related tree species on the Pacific Coast of the United States. We estimate the discounted cost of oak treatment, removal, and replacement on developed land in California communities using simulations of P. ramorum spread and infection risk over the next decade (2010-2020). An estimated 734 thousand oak trees occur on developed land in communities in the analysis area. The simulations predict an expanding sudden oak death (SOD) infestation that will likely encompass most of northwestern California and warrant treatment, removal, and replacement of more than 10 thousand oak trees with discounted cost of $7.5 million. In addition, we estimate the discounted property losses to single family homes of $135 million. Expanding the land base to include developed land outside as well as inside communities doubles the estimates of the number of oak trees killed and the associated costs and losses. The predicted costs and property value losses are substantial, but many of the damages in urban areas (e.g. potential losses from increased fire and safety risks of the dead trees and the loss of ecosystem service values) are not included. Copyright © 2010 Elsevier Ltd. All rights reserved.

Community composition of root-associated fungi in a Quercus-dominated temperate forest: “codominance” of mycorrhizal and root-endophytic fungi

Science.gov (United States)

Toju, Hirokazu; Yamamoto, Satoshi; Sato, Hirotoshi; Tanabe, Akifumi S; Gilbert, Gregory S; Kadowaki, Kohmei

2013-01-01

In terrestrial ecosystems, plant roots are colonized by various clades of mycorrhizal and endophytic fungi. Focused on the root systems of an oak-dominated temperate forest in Japan, we used 454 pyrosequencing to explore how phylogenetically diverse fungi constitute an ecological community of multiple ecotypes. In total, 345 operational taxonomic units (OTUs) of fungi were found from 159 terminal-root samples from 12 plant species occurring in the forest. Due to the dominance of an oak species (Quercus serrata), diverse ectomycorrhizal clades such as Russula, Lactarius, Cortinarius, Tomentella, Amanita, Boletus, and Cenococcum were observed. Unexpectedly, the root-associated fungal community was dominated by root-endophytic ascomycetes in Helotiales, Chaetothyriales, and Rhytismatales. Overall, 55.3% of root samples were colonized by both the commonly observed ascomycetes and ectomycorrhizal fungi; 75.0% of the root samples of the dominant Q. serrata were so cocolonized. Overall, this study revealed that root-associated fungal communities of oak-dominated temperate forests were dominated not only by ectomycorrhizal fungi but also by diverse root endophytes and that potential ecological interactions between the two ecotypes may be important to understand the complex assembly processes of belowground fungal communities. PMID:23762515

Using Paleoecology to Inform Land Management as Climates Change: An Example from an Oak Savanna Ecosystem

Science.gov (United States)

Spencer, Jessica D.; Brunelle, Andrea; Hepola, Tim

2017-12-01

Oak savanna, a transitional ecosystem between open prairie and dense oak forest, was once widespread in Minnesota. Upon European settlement much of the oak savanna was destroyed. Recently, efforts to restore this ecosystem have increased and often include the reintroduction of fire. Though fire is known to serve an important role within oak savannas, there are currently few studies which address fire regimes on timescales longer than the last century. This research presents a paleoecological history of Sherburne National Wildlife Refuge (SNWR) in MN, USA, spanning the last 8000 years. The objectives of this study were to use charcoal, pollen, and magnetic susceptibility of lake sediments collected from Johnson Slough (JS) within the refuge to evaluate the natural range of variability and disturbance history of the oak savanna within the refuge, assess the success of current restoration strategies, and add to the regional paleoecological history. The mid/late Holocene period of the JS record shows a period of high fire activity from ca. 6500 to 2600 cal year BP, with a shift from prairie to oak savanna occurring over this same period. A (possibly agricultural) disturbance to JS sediments affected the period from ca. 2600 cal year BP to 1963 AD, which includes the time of Euro-American settlement. However, the destruction and subsequent restoration of the oak savanna is evident in a pollen ratio of Quercus:Poaceae, indicating that current restoration efforts have been successful at restoring the oak savanna to within the natural range of variability seen just prior to destruction.

Influence of the botanical origin and toasting level on the ellagitannin content of wines aged in new and used oak barrels.

Science.gov (United States)

Navarro, María; Kontoudakis, Nikolaos; Gómez-Alonso, Sergio; García-Romero, Esteban; Canals, Joan Miquel; Hermosín-Gutíerrez, Isidro; Zamora, Fernando

2016-09-01

The influence of the botanical origin (French oak: Quercus petraea and American oak: Quercus alba) and different toasting levels (light, medium and heavy) on the ellagitannin content of wines aged in oak barrels has been studied. This took place in two consecutive vintages in order to study what happens after the barrels have been already used for one year with another wine. This study was carried out with two red wines (Cabernet Sauvignon) and with two decolored white wines (Macabeo) from vintages 2012 and 2013 in order to work with a simpler matrix which facilitates chemical analysis. The results show that the botanical origin, toasting level and the number of times that the barrels have been used exert a major influence on the final ellagitannin concentration. In general, the behavior of all the individual ellagitannins was very similar to that described for the total ellagitannins. Briefly, the levels of total ellagitannins concentration in the decolored white wine aged for 12months in new French barrels ranged between 31.2mg/L in the lightly toasted and 4.7mg/L in the heavy toasted. In contrast, these levels were quite lower in American new barrels ranging between 3.6mg/L and 0.9mg/L. Finally, the total ellagitannin concentration decreased an average of 63% in the wines aged in the one year used barrels. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dendrochronological Investigations of Valonia Oak Trees in Western Greece

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Andreas Papadopoulos

2016-06-01

Full Text Available Background and Purpose: Valonia oak (Quercus ithaburensis subsp. macrolepis (Kotschy Hedge & Yalt. is an east Mediterranean endemic, xerothermic and deciduous tree of particular interest in forestry. There has been a growing demand lately to include the species in reforestations in Greece which also increased the interest to investigate its response to climate change. The main purpose of this research is to study valonia oak from a dendrochronological – dendroclimatological point of view within its Mediterranean distribution range. Materials and Methods: Sampling took place in characteristic valonia oak stands where cross sections or tree-cores were taken from 40 trees. The cross sections and the tree-cores were prepared and cross-dated using standard dendrochronological methods and tree-ring widths were measured to the nearest 0.001 mm using the Windendro software program. The ARSTAN program was used to standardize the tree-ring data and to calculate dendrochronological statistical parameters. The inter-annual variability of tree-ring width and the radial growth trend were examined. Finally, tree-ring widths to climate relationships were calculated by orthogonal regression in combination with the bootstrap procedure using master residual chronology and monthly precipitation, temperature data and scPDSI drought index, from October of the n-1 year up to November of the n year. Results: The master chronology of valonia oak trees in Western Greece reaches 365 years, with an average ring width of 0.89 mm and with mean sensitivity being 0.21. The variation of the tree-ring widths indicates the influence of climate and human intervention in the past. Tree-ring to climate relationships show that valonia oak growth is positively affected by precipitations in January and March and by drought reduction during June and July. Conclusions: Valonia oak in Western Greece is a species of great interest for dendrochronological and dendroclimatological studies

Management of Maritime Communities for Threatened and Endangered Species.

Science.gov (United States)

1998-05-01

S) mulletbush (B. halimifolia) (S) American barberry (Berchemia scandens) (L) Virginia creeper (Parthenocissus quinquefolia) (L) winged sumac...include coastal red cedar {Juniperus silicicola), red bay ( Persea borbonia), live oak (Quercus virginiana) and cabbage palm (Sabal palmetto; Stalter...scattered pines. The canopy is composed of live oak, slash pine, myrtle oak (Quercus myrtifolia), American olive (Osmanthus americanus), Chapman’s oak

Adaptive and plastic responses of Quercus petraea populations to climate across Europe

DEFF Research Database (Denmark)

Sáenz-Romero, Cuauhtémoc; Lamy, Jean-Baptiste; Ducousso, Alexis

2017-01-01

geographically diverse populations. The tests were planted on 23 field sites in six European countries, in order to expose them to a wide range of climates, including sites reflecting future warmer and drier climates. By assessing tree height and survival, our objectives were twofold: (i) to identify the source......How temperate forests will respond to climate change is uncertain; projections range from severe decline to increased growth. We conducted field tests of sessile oak (Quercus petraea), a widespread keystone European forest tree species, including more than 150 000 trees sourced from 116...... of differential population responses to climate (genetic differentiation due to past divergent climatic selection vs. plastic responses to ongoing climate change) and (ii) to explore which climatic variables (temperature or precipitation) trigger the population responses. Tree growth and survival were modeled...

Effects of acorn size and mass on seedling quality of northern red oak (Quercus rubra)

Science.gov (United States)

Stacy L. Clark; Scott E. Schlarbaum

2018-01-01

Oaks are not sustainable in many upland temperate forests because of poor recruitment resulting from natural regeneration. Artificial regeneration is an alternative to natural regeneration, but is difficult, in part, due to large variation in seedling quality.  In this study, we examined the effects of acorn size and mass on nursery...

[Tree-ring growth responses of Mongolian oak (Quercus mongolica) to climate change in southern northeast: a case study in Qianshan Mountains].

Science.gov (United States)

Teng, Li; Xing-Yuan, He; Zhen-Ju, Chen

2014-07-01

Mongolian oak is one of the most important broad-leaved tree species in forests, Northeast China. Based on the methodology of dendrochronology, the variations of tree ring radial growth of Mongolian oak in Qianshan Mountains, south of Northeast China, were analyzed. Combined with the temperature and precipitation data from meteorological stations since 1951, the relationships between standardized tree ring width chronology and main climatic factors were analyzed. In this region, the precipitation between April and July of the current year had an significant relationship with the tree ring width of Mongolian oak, and was the main factor limiting the radial growth. The extreme maximum temperature of May was also a key factor influencing the tree ring width, which had a significant on the tree ring width of Mongolian oak. The precipitation in April had a significant and stable relationship with the growth of Mongolian oak since the 1950s. The 'divergence problem' was found in the study area, which the sensitivity of tree growth to summer temperature reduced since the 1980s. The tree growth response to temperature showed a seasonal change from summer to spring.

A new Middle Pleistocene interglacial record from Denmark: Chronostratigraphic correlation, palaeovegetation and fire dynamics

DEFF Research Database (Denmark)

Kuneš, Petr; Kjærsgaard Sørensen, Malene; Buylaert, Jan-Pieter

2013-01-01

trees (Quercus, Ulmus and Tilia) during its mesocratic stage. Macrofossil analysis allowed identification to species level for Quercus robur, Picea abies and two mosses. Conifers (Pinus and Picea) dominate the pollen record of the interglacial sequence, and the occurrence of Larix pollen in the top part...... of the interglacial record as well as in the interstadial sediments is especially indicative of this interglacial. The overall diversity of tree genera is rather low. These biostratigraphical features suggest that Trelde Klint is unique among Danish records, but it is similar to records from northern Germany...

Characterization of Acorn Fruit Oils Extracted from Selected Mediterranean Quercus Species

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Al-Rousan, W. M.

2013-12-01

Full Text Available The present study is aimed to identifying the acorn fruit oil composition of three Mediterranean white oak group species, Quercus aegilops (QA, Quercus infectoria (QI, and Quercus calliprinus (QC. Samples were estimated for the oil contents of acorn fruits, oil chemical and physical constants, fatty acid profile, tocopherols, phenolic compounds, and sterols.The oil content, expressed as dry weight, was found to be 3.40-7.51%. The physical and chemical constants included specific gravity 0.912-0.922, refractive index 1.4529-1.4645, specific extinction at 232 nm 2.497-2.536 and at 270 nm 1.495-2.037, iodine value 75.2-87.6, and saponification value 192.6-219.4. The fatty acid compositions were determined by GC as methyl esters. The most abundant fatty acids were oleic (53.3-56.1%, linoleic 21.3-23.4%, palmitic 17.8-18.7%, linolenic 1.5-1.6% and stearic acid 1.02-1.60%. The Tocopherol content was high in the range of 1440-1783 mg kg-1, γ-tocopherol constituted 84-91% of total tocopherols. Phenolic compounds were in remarkable amounts in all the three species 84-109 mg gallic acid kg-1 oil. Total sterol contents were between 2040-2480 mg kg-1 oil, with β-sitosterol being the main component comprising of 77.20-84.61%, followed by ∆5-avenasterol (5.8-11.4%, campesterol (3.6-4.5%, and stigmasterol (2.6-3.8. The cholesterol content was relatively high (0.42-0.55%.El presente estudio tuvo como objetivo identificar la composición de aceites de bellota de tres especies del grupo del roble blanco del Mediterráneo, Quercus Aegilops (QA, Quercus infectoria (QI y Quercus calliprinus (QC. Las muestras fueron evaluadas por el contenido de aceite, parámetros físico-químicos del aceite, perfil de ácidos grasos, tocoferoles, compuestos fenólicos y esteroles. El contenido de aceite, expresado en peso seco encontrado fue de 3,40 a 7,51%. Las constantes físico-químicas fueron: densidad 0,912-0,922, índice de refracción 1,4529 a 1,4645, extinción espec

Effect of human disturbance on seed and seedling distribution of the Andean Oak (Quercus humboldtii Bonpl., Fagaceae) in the Colombian Eastern Cordillera

International Nuclear Information System (INIS)

Guerrero Rodriguez, Sandra Bibiana; Paz Camacho, Erika Andrea; Parrado Rosselli, Angela

2010-01-01

Animals affect the spatial occupation patterns of tropical forest plants throughout the seed dispersal they perform. Therefore, changes in vertebrate populations by human disturbance might affect re generation dynamics of plant species. We studied differences in the spatial distribution of seeds and seedlings of the Andean oak (Quercus humboldtii) between two nearby forests with contrasting levels of anthropogenic influence in the Colombian Andes. Density and spatial distribution of seedlings were evaluated in 490 and 484 1 m2 plots located in a 28 ha area, in the high and low disturbed site, respectively. In each plot, all seedlings found were sampled and classified into three age categories. Density and spatial distribution of seeds were evaluated in 0.25 m 2s ubplots placed in the same plots described above. Results showed a higher number and density of seedlings in the high disturbed site, as well as a marked decrease in seedling density as age increases. Distances to the nearest neighbour were shorter in the high disturbed site for all seedlings and each age category, in contrast to the low disturbed site. Indexes of spatial distribution indicate an aggregated pattern in the most disturbed site, while a uniform pattern in the low disturbed one. Seeds also exhibited an aggregated pattern in the high disturbed site and a higher seed predation by invertebrates. Results seemed to be a consequence of forest fragmentation and a decrease of vertebrate seed dispersers, seed predators and herbivores associated to the regeneration processes of the species. These results provide important information for the forest management and restoration activities, since in order to maintain plant populations in the long term, presence and viable populations of seed dispersers should be also maintained.

Isoprene emission rates and fluxes measured above a Mediterranean oak ( Quercus pubescens) forest

Science.gov (United States)

Simon, V.; Dumergues, L.; Bouchou, P.; Torres, L.; Lopez, A.

2005-03-01

The present work, carried out as part of the European fiEld experimentS to COnstrain Models of atmospheric Pollution and Transport of Emissions project (ESCOMPTE), brings a new contribution to the inventory of the main natural hydrocarbons sources that are liable to participate in the production of ozone. The measurement campaign was conducted in Montmeyan, a site close to Marseilles (France), with the aim of quantifying the terpenic emission pattern and the behaviour of Quercus pubescens, an important Mediterranean tree species. Biogenic emissions by Q. pubescens were determined by the enclosure of an intact branch of this tree in a Teflon cuvette. The total monoterpenic emission rates thus recorded were found to reach maximum values ranged between 40 and 350 μg g Dry Weight-1 h -1. Emissions were correlated strongly with leaf temperature and Photosynthetic Active Radiation (PAR). The fluxes were also determined by extrapolating the results of the enclosure method and by using aerodynamic gradient method. They reach around 73 mg m -2 h -1 with the first method and 55 mg m -2 h -1 with the second one. The obtained values fit with a maximal ratio of 2.

Field monoterpene emission of Mediterranean oak (Quercus ilex) in the central Iberian Peninsula measured by enclosure and micrometeorological techniques: Observation of drought stress effect

Science.gov (United States)

Plaza, J.; NúñEz, L.; Pujadas, M.; PéRez-Pastor, R.; Bermejo, V.; GarcíA-Alonso, S.; Elvira, S.

2005-02-01

An experimental characterization of biogenic emission from Quercus ilex ssp. rotundifolia in a forest near Madrid, Spain, was carried out in the early autumn of the years 2000-2003. A dynamic branch enclosure technique was implemented to determine the monoterpene emission rates of this evergreen oak species during the 2000 and 2001 campaigns. Major compounds emitted during both measurement periods were limonene, α-pinene, β-pinene, sabinene, and myrcene. In the 2000 field campaign the light- and temperature-dependent model of [1993] did not fit the data due to drastic reductions of emission rates (and leaf gas exchange related parameters) observed at high air temperature and low air humidity (high water vapor pressure deficit). This plant physiological activity depletion and the subsequent emission reduction were attributed to severe water soil deficit conditions, as precipitation was very scarce during the growing season. In contrast, during the 2001 field campaign, neither emission nor physiological activity showed strong decreases in hot days. A good fit of experimental data to Guenther model was achieved in this field campaign (r2 = 0.90), and linear regression gave a standard emission factor (ES) of 14.0 μg gdw-1 h-1 (gdw is grams dry weight). Soil moisture was presumably higher than during the 2000 campaign due to recent rain events. With the purpose of documenting the drought stress effect at canopy level, monoterpene oak fluxes were measured by the modified Bowen ratio micrometeorological technique throughout the 2001 field campaign and in the late summer of 2002 and 2003. The measured emission by both techniques showed a reasonably good correlation, although micrometeorological fluxes were, in general, lower than upscaled branch emission rates. According to Guenther's parameterization, standard emission fluxes (FS) of 0.30 μg m-2 s-1 (r2 = 0.61) and 0.28 μg m-2 s-1 (r2 = 0.67) were derived for the 2001 and 2002 field campaigns, respectively. However

The Effects of Intermittent Flooding on Seedlings of Three Forest Species

Science.gov (United States)

P.H. Anderson; S.R. Pezeshki

1999-01-01

Under greenhouse conditions, seedlings of three forest species, baldcypress (Taxodium distichum), nuttall oak (Quercus nuttallii), and swamp chestnut oak (Quercus michauxii) were subjected to an intermittent flooding and subsequent physiological and growth responses to such conditions were evaluated....

Ecophysiological characteristics and cadmium accumulation in Downy Oak (Quercus pubescens Willd.

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Cocozza C

2012-10-01

Full Text Available Heavy metals provoke environmental pollution with potentially toxic effects on human and plants systems. Recently, investigations are conducted on plants that may play a relevant role on pollutants absorption or stabilization, focusing on fast growing tree species in agronomic conditions; little is known on the effects of contaminants on tree species colonizing abandoned fields to be used in restoration ecology. The effects of Cd on photosynthetic performance and metal accumulation were investigated in Quercus pubescens Willd. seedlings grown in pots containing a mixture of sand, clay, turf and Cd-treatments (0, 25 and 75 mg kg-1 dry soil. The studied photosynthetic parameters (Asat= net phytosynthesis; Rday= day respiration; Γcomp= CO2 compensation point; Vcmax= maximum carboxylation rate; Jmax = electron transport rate; TPU = triose phosphate use; Ci/Ca = ratio of intercellular (Ci to ambient (Ca [CO2] (Ci/Ca; Jmax/Vcmax = ratio; (gsmax = maximum stomatal conductance; (lg = stomatal conductance estimated relative to the photosynthetic rate; (Fv/Fm = maximum quantum yield of PSII photochemistry; (ΔF/F’m = effective photochemical efficiency varied progressively with increasing Cd concentration in the soil, highlighting a negative impact on photosynthetic potential and PSII functioning. Approximately 10% of added Cd was found to be extractable from the substrate, at the maximum concentration applied, with about 12 and 0.75 as bioaccumulation and translocation factors, respectively. Analogously, Cd accumulated up to 34, 30 and 46 mg kg−1 in leaves, stem and roots, respectively. While it is not possible to extrapolate from the present study with seedlings to effects on mature pine trees, there are clear implications for regeneration in soils contaminated with heavy metals, which may lead to ecosystem deterioration.

Environmental Impact Analysis Process. Final Environmental Impact Statement. Supersonic Flight Operations in the Reserve Military Operations Area, Holloman, New Mexico

Science.gov (United States)

1983-01-01

Juniper, one-seed Juniperus monosperma Juniper, rocky mountain Juniperus scopulorum Oak, Gambel Querqus gambeli Oak, gray Quercus grisea Oak, silverleaf... Quercus hypoleucoides Pine, Chihuahua (localized) Pinus leiophylla Pine, pinyon Pinus edulis Pine, ponderosa Pinus ponderosa Pine, southwestern white...stansburiana Currant, Golden Ribes aureum Grape, Canyon Vitis Arizonica Groundsel, Ragwort Senecio multicapitatus Morning Glory, Red Starflower Ipomea

Preliminary Guide to the Onsite Identification and Delineation of the Wetlands of the South Atlantic United States.

Science.gov (United States)

1982-05-01

shield) Ceratophyilum demersum (Coontail) Myriophyllum spp. (Watermilfoil) Nelumbo lutea ( American lotus) Nuphar luteum (Spatterdock) Nymphaea odorata...Overcup oak) Quercus palustris (Pin oak) Quercus phelios (Willow oak) Ulmus americana ( American elm) UlmuS rubra (Slippery elm) c. Atlantic White...var. biflora (Swamp black gum) Persea borbonia (Red bay) Pinus serotina (Pond pine) Smilax laurifolia (Bamboo vine) Sphagnum spp. (Sphagnum moss

Transpiration of montane Pinus sylvestris L. and Quercus pubescens Willd. forest stands measured with sap flow sensors in NE Spain

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R. Poyatos

2005-01-01

Full Text Available Stand transpiration was measured during the 2003 and 2004 growing seasons using heat dissipation sap flow sensors in a Scots pine (Pinus sylvestris L. and a pubescent oak (Quercus pubescens Willd. forests located in a montane area of the Eastern Pyrenees (NE Spain. The first aim of the study was to assess the differences in quantitative estimates of transpiration (Ec and the response to evaporative demand of the two stands. Over the studied period of 2003, characterised by a severe drought episode during the summer, the oak stand (Ec was only 110 mm compared to the 239 mm transpired by the Scots pine stand, although the ratio of transpiration to reference evapotranspiration (Ec/ET0 in the oak stand compares well with the expected values predicted for low leaf area index (LAI oak forests in southern Europe. Scots pine showed a strong reduction in (Ec/ET0 as the drought developed, whereas pubescent oak was less affected by soil moisture deficits in the upper soil. As a second objective, and given the contrasting meteorological conditions between 2003 and 2004 summer periods, the interannual variability of transpiration was studied in the Scots pine plot. Rainfall during the summer months (June-September in 2003 was almost 40% less than in the same interval in 2004. Accordingly, transpiration was also reduced about 25% in 2003. Finally, Scots pine data from 2003 and 2004 was used to calibrate a simple transpiration model using ET0 and soil moisture deficit (SMD as input variables, and implicitly including stomatal responses to high vapour pressure deficits (Dd and soil water status.

Drivers of Productivity Trends in Cork Oak Woodlands over the Last 15 Years

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Maria João Santos

2016-06-01

Full Text Available Higher biodiversity leads to more productive ecosystems which, in turn, supports more biodiversity. Ongoing global changes affect ecosystem productivity and, therefore, are expected to affect productivity-biodiversity relationships. However, the magnitude of these relationships may be affected by baseline biodiversity and its lifeforms. Cork oak (Quercus suber woodlands are a highly biodiverse Mediterranean ecosystem managed for cork extraction; as a result of this management cork oak woodlands may have both tree and shrub canopies, just tree and just shrub canopies, and just grasslands. Trees, shrubs, and grasses may respond differently to climatic variables and their combination may, therefore, affect measurements of productivity and the resulting productivity-biodiversity relationships. Here, we asked whether the relationship between productivity and climate is affected by the responses of trees, shrubs, and grasses in cork oak woodlands in Southern Portugal. To answer this question, we linked a 15-year time series of Enhanced Vegetation Index (EVI derived from Landsat satellites to micrometeorological data to assess the relationship between trends in EVI and climate. Between 2000 and 2013 we observed an overall decrease in EVI. However, EVI increased over cork oaks and decreased over shrublands. EVI trends were strongly positively related to changes in relative humidity and negatively related to temperature. The intra-annual EVI cycle of grasslands and sparse cork oak woodland without understorey (savannah-like ecosystem had higher variation than the other land-cover types. These results suggest that oaks and shrubs have different responses to changes in water availability, which can be either related to oak physiology, to oaks being either more resilient or having lagged responses to changes in climate, or to the fact that shrublands start senesce earlier than oaks. Our results also suggest that in the future EVI could improve because the

variability in foliar phenolic composition of several quercus species in northern mexico

International Nuclear Information System (INIS)

Salazar, J.A.A.; Antuna, E.M.; Abarca, N.A.; Alvarado, E.A.D.

2015-01-01

Quantitative and qualitative composition of the foliar phenolic compounds were investigated in 81 individual specimens of several white oak species (Quercus spp.). The trees were growing in twelve locations in Durango, Mexico. The phenol profiles were determined by HPLC-DAD and a Folin-Ciocateuprocedure. The results revealed that: (i) the foliar phenol profiles of all species analysed were complex and formed by 6 to 30 compounds, (ii) the flavonols mostly quercetin glycoside, isorhamnetin glycoside, kaempferol glycoside and phenolic acids were the main identified compounds, (iii) there was a high intra and inter-specific variability in the foliar phenol profiles both at the quantitative and qualitative levels, and (iv) the foliar phenol profiles indicated a slight species-specific tendency for phenols to be accumulated, although this was not clearly distinguished. Significant differences (P < 0.05) in the content and composition of the foliar flavonoids between species were observed due to the large environmental and soil conditions variability between localities. (author)

The Effect of Raffaelea quercus-mongolicae Inoculations on the Formation of Non-conductive Sapwood of Quercus mongolica.

Science.gov (United States)

Torii, Masato; Matsuda, Yosuke; Seo, Sang Tae; Kim, Kyung Hee; Ito, Shin-Ichiro; Moon, Myung Jin; Kim, Seong Hwan; Yamada, Toshihiro

2014-06-01

In Korea, mass mortality of Quercus mongolica trees has become obvious since 2004. Raffaelea quercus-mongolicae is believed to be a causal fungus contributing the mortality. To evaluate the pathogenicity of the fungus to the trees, the fungus was multiple- and single-inoculated to the seedlings and twigs of the mature trees, respectively. In both the inoculations, the fungus was reisolated from more than 50% of inoculated twigs and seedlings. In the single inoculations, proportions of the transverse area of non-conductive sapwood at inoculation points and vertical lengths of discoloration expanded from the points were significantly different between the inoculation treatment and the control. In the multiple inoculations, no mortality was confirmed among the seedlings examined. These results showed that R. quercus-mongolicae can colonize sapwood, contribute to sapwood discoloration and disrupt sap flows around inoculation sites of Q. mongolica, although the pathogenicity of the fungus was not proven.

Late Quaternary developments of Mediterranean oaks in the Atlantic domain of the Iberian Peninsula: The case of the Cantabrian region (N Spain)

Science.gov (United States)

Uzquiano, P.; Ruiz-Zapata, MaB.; Gil-Garcia, MaJ.; Fernández, S.; Carrión, J. S.

2016-12-01

A synthesis of the occurrence of the evergreen oak (Quercus ilex-type) in the Cantabrian region (northern Spain) is presented on the basis of integrated charcoal and pollen analyses. Archaeological charcoal comes largely from sites along the littoral and pre-littoral territories of the Basque Country, Cantabria and Asturias dated from 45 to 3.7 Kyr cal BP, and culturally ranging from Mousterian to Iron Age. Pollen information is produced from a few archaeological sites but mainly from peats and lake sediments. Q. ilex-type is observed as early as at 45-30 Kyr cal BP, with sporadic occurrences in vegetation contexts dominated by Pinus sylvestris-type, which was widely exploited by Mousterian and Aurignacian inhabitants. Afterwards, during the Upper Palaeolithic, there is an important decline, and Q. ilex-type is hardly present between 29 and 15 Kyr cal BP, with open environments dominated by heathland shrubs. From Late Magdalenian onwards, Q. ilex-type expanded again, remaining in the landscape of the Cantabrian region throughout the Holocene, although subordinated in deciduous oak forests under the influence of oceanic climate conditions. Q. ilex-type had a more favourable position than deciduous Quercus across the Cantabrian southern slopes and northwest of the adjacent Iberian Cordillera, where oceanic influences have become attenuated by summer drought and continentality.

La Farge Lake, Kickapoo River, Vernon County, Wisconsin, Final Environmental Statement.

Science.gov (United States)

1972-02-18

alternifolia (Wingstem), Asimina. triloba (Paw Paw), Aster vimineus, Buchloe dactylodes (Buffalo Grass), Carya glabra (Sweet Pg-ut), illinoensis (Pecan...black oak (Quercus velutina), white oak (Quercus alba), and hickory ( Carya cordiformes) generally occupy the drier uplands and slopes with south and

Morphological and physiological divergences within Quercus ilex support the existence of different ecotypes depending on climatic dryness.

Science.gov (United States)

Peguero-Pina, José Javier; Sancho-Knapik, Domingo; Barrón, Eduardo; Camarero, Julio Jesús; Vilagrosa, Alberto; Gil-Pelegrín, Eustaquio

2014-08-01

Several studies show apparently contradictory findings about the functional convergence within the Mediterranean woody flora. In this context, this study evaluates the variability of functional traits within holm oak (Quercus ilex) to elucidate whether provenances corresponding to different morphotypes represent different ecotypes locally adapted to the prevaling stress levels. Several morphological and physiological traits were measured at leaf and shoot levels in 9-year-old seedlings of seven Q. ilex provenances including all recognized morphotypes. Plants were grown in a common garden for 9 years under the same environmental conditions to avoid possible biases due to site-specific characteristics. Leaf morphometry clearly separates holm oak provenances into 'ilex' (more elongated leaves with low vein density) and 'rotundifolia' (short and rounded leaves with high vein density) morphotypes. Moreover, these morphotypes represent two consistent and very contrasting functional types in response to dry climates, mainly in terms of leaf area, major vein density, leaf specific conductivity, resistance to drought-induced cavitation and turgor loss point. The 'ilex' and 'rotundifolia' morphotypes correspond to different ecotypes as inferred from their contrasting functional traits. To the best of our knowledge, this is the first time that the combined use of morphological and physiological traits has provided support for the concept of these two holm oak morphotypes being regarded as two different species. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Air pollution effects on quercus ilex plants; Effetti dell`inquinamento atmosferico sulle leccete dei monti Climiti (Sicilia sud-Orientale)

Energy Technology Data Exchange (ETDEWEB)

Pavone, P.; Salmeri, C. [Catania Univ. (Italy), Dip. di Botanica; Spampinato, G. [Reggio Calabria Univ. (Italy), Dip. di Agrochimica e Agrobiologia; Fallico, R.; Ferrante, M. [Catania Univ. (Italy), Ist. di Igiene e Medicina Preventiva

1996-07-01

To test air pollution effects on natural forest vegetation, the soil chemistry and the floristic composition of two Quercus ilex L. woods in the Hyblean region (S-E Sicily), unequally exposed to air pollutants are compared. Acidification phenomena are investigated by the soil chemical changes between the trunk base areas, affected by stem flow water, and the surrounding soil, only influenced by canopy drip. Soil chemical changes, floristic poorness and direct damage to the Q. ilex leaves are only detected in the Climiti Mountains holm-oak woods, located near the Siracusa petrochemical complex, while they do not appear at Cava d`Ispica, sited far from any industry and seldom exposed to winds carrying pollutants.

Production of anticandidal cotton textiles treated with oak gall extract

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Ahmed A. Tayel

Full Text Available Candida albicans, one of the most dreadful fungal pathogens threatening humans, could not be easily prevented. The anticandidal activity of oak gall extract, Quercus infectoria (QIE, was investigated as a potential natural alternative to synthetic and chemical fungicides. QIE anticandidal potentiality was confirmed using both qualitative and quantitative assays. Cotton textiles were treated with QIE and then evaluated as anticandidal fabrics. QIE-treated textiles had a potent anticandidal activity, which could completely inhibit the inoculated C. albicans cells. The durability of anticandidal activity in QIE-treated textiles almost completely disappeared after the fourth laundering cycle. QIE could be recommended, however, as a potent anticandidal agent for preparing antiseptic solutions and emulsions and as a finishing agent for manufacturing anticandidal disposable diapers and hygienic clothes.

Environmental Assessment of Short-Term Construction Projects at the 150th Fighter Wing, New Mexico Air National Guard, Kirtland Air Force Base, New Mexico

Science.gov (United States)

2003-01-01

smaller tree species include one-seeded juniper (Juniperus monosperma) and occasionally low oaks, such as gray oak ( Quercus grisea). Wildlife in...Cercocarpus montanus), yucca, gambel oak ( Quercus gambelii), prickley pear (Opuntia phaeacantha), blue grama (Bouteloua gracilis), sideoats grama (B...Engelmann spruce (Picea engelmanni), subalpine fir (Abies lasiocarpa) (in the north), and corkbark fir (Abies lasiocarpa var. arizonica ) (in the south) are

Light and soil humidity influencing oak seedling growth and physiology in mixed hardwood gaps

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Raddi S

2009-06-01

Full Text Available In “S. Rossore, Migliarino, Massaciuccoli” Natural Park (Pisa, I six-month-old pedunculate oak seedlings (Quercus robur L. were transplanted within natural gaps of a mixed oak forest. Micro-environmental variability for radiation and water soil content were measured for 145 seedlings during the year. Irradiation relative to the open field (IR ranged from 5% to 57%. Seven classes of IR each with 20 seedlings were selected. Leaf mass per area was strongly influenced by IR. In the first 3 years survival was high (95, 76 and 75%, respectively and seedling reached 14±6 cm, 27±13 cm and 39±19 (sd cm of height. Even if IR and soil water content (SWC were negatively associated, indicating a lower SWC at the centre of the gaps, height and its relative growth rate increased with IR (explored range: 8-40% with a significant interaction with SWC in the 1st year, indicating the positive effect of soil moisture. In the 3rd year dimensional traits were higher in L+W+ (high light and humidity followed by L-W+ (low light and high humidity, L+W- and finally by L-W-. Summer drought typical of the Mediterranean climate was evaluated by chlorophyll fluorescence of PSII on apical leaves of seedlings and mature trees at the beginning (21 June and in mid-summer (20 July. While in June physiological traits did not differ between low and high IR, in mid-summer (at the peak of water-stress seedlings of the two highest light classes showed chronic photoinhibition (Fv/Fm<0.75 and an increase in thermal dissipation (D by constitutive term (Dc=1-Fv/Fm and by regulated mechanisms of dissipation through xanthophyll-cycle term (Dx. Moreover, in July seedling leaf physiology largely differed with IR: leaves acclimated to high IR have higher photosynthetic potentialities, as shown by electron transport rate (ETR and quantum yield (P at saturating light maintained by an increase of the fraction of open reaction centres (qP, counterbalancing the efficiency decrease of the

Morphological indicators of stock quality and field performance of red oak (Quercus rubra L.) seedling underplanted in a central Ontario shelterwood

Science.gov (United States)

Daniel C. Dey; William C. Parker

1997-01-01

Initial stem diameter of bareroot red oak planting stock was a better morphological indicator of future height and diameter growth in a shelterwood underplanting than were initial shoot length and number of first-order lateral roots. Stem diameter near the root collar provides an integrated measure of the growth potential of red oak planting stock because of its strong...

Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle.

Science.gov (United States)

Musa, Najihah; Andersson, Klas; Burman, Joseph; Andersson, Fredrik; Hedenström, Erik; Jansson, Nicklas; Paltto, Heidi; Westerberg, Lars; Winde, Inis; Larsson, Mattias C; Bergman, Karl-Olof; Milberg, Per

2013-01-01

The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak) was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata) were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management.

Using Sex Pheromone and a Multi-Scale Approach to Predict the Distribution of a Rare Saproxylic Beetle.

Directory of Open Access Journals (Sweden)

Najihah Musa

Full Text Available The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management.

Self-thinning dynamics in cork oak woodlands: providing a baseline for managing density

International Nuclear Information System (INIS)

Fonseca, T.; Monteiro, L.; Enes, T.; Cerveira, A.

2017-01-01

Aim of study: The study aims to evaluate the maximum potential stocking level in cork oak (Quercus suber L.) woodlands, using the ecologically-based size-density relationship of the self-thinning law. Area of study: The study area refers to cork oak forests in mainland Portugal, distributed along its 18 districts from north to south. Material and Methods: A dataset with a total of 2181 observations regarding pure cork oak stands was collected from the Portuguese Forest Inventory (NFI) databases and from research plots. The dataset was subjected to two filtering procedures, one more restrictive than the other, to select the stands presenting the higher stocking values. The two resulting subsets, with 116 and 36 observations, from 16 and 10 districts of mainland Portugal, respectively, were then used to assess and describe the allometric relationship between tree number and their mean diameter. Main results: The allometric relationship was analysed and modelled using the log transformed variables. A slightly curvilinear trend was identified. Thus, a straight line and a curve were both fitted for comparison purposes. Goodness-of-fit statistics point out for a good performance when the data is set to the uppermost observed stocking values. A self-thinning line for cork oak was projected from the estimated relationship. Research highlights: The self-thinning model can be used as an ecological approach to develop density guidelines for oak woodlands in a scenario of increasing cork demands. The results indicate that the recommendations being applied in Portugal are far below the maximal potential stocking values for the species. It is therefore of the utmost importance to review the traditional silvicultural guidelines and endorse new ones.

Self-thinning dynamics in cork oak woodlands: providing a baseline for managing density

Energy Technology Data Exchange (ETDEWEB)

Fonseca, T.; Monteiro, L.; Enes, T.; Cerveira, A.

2017-11-01

Aim of study: The study aims to evaluate the maximum potential stocking level in cork oak (Quercus suber L.) woodlands, using the ecologically-based size-density relationship of the self-thinning law. Area of study: The study area refers to cork oak forests in mainland Portugal, distributed along its 18 districts from north to south. Material and Methods: A dataset with a total of 2181 observations regarding pure cork oak stands was collected from the Portuguese Forest Inventory (NFI) databases and from research plots. The dataset was subjected to two filtering procedures, one more restrictive than the other, to select the stands presenting the higher stocking values. The two resulting subsets, with 116 and 36 observations, from 16 and 10 districts of mainland Portugal, respectively, were then used to assess and describe the allometric relationship between tree number and their mean diameter. Main results: The allometric relationship was analysed and modelled using the log transformed variables. A slightly curvilinear trend was identified. Thus, a straight line and a curve were both fitted for comparison purposes. Goodness-of-fit statistics point out for a good performance when the data is set to the uppermost observed stocking values. A self-thinning line for cork oak was projected from the estimated relationship. Research highlights: The self-thinning model can be used as an ecological approach to develop density guidelines for oak woodlands in a scenario of increasing cork demands. The results indicate that the recommendations being applied in Portugal are far below the maximal potential stocking values for the species. It is therefore of the utmost importance to review the traditional silvicultural guidelines and endorse new ones.

Exploring Growth Variability and Crown Vitality of Sessile Oak (Quercus petraea) in the Czech Republic

Czech Academy of Sciences Publication Activity Database

Rybníček, Michal; Čermák, P.; Žid, T.; Kolář, Tomáš; Trnka, Miroslav; Büntgen, Ulf

2015-01-01

Roč. 42, č. 1 (2015), s. 17-27 ISSN 1733-8387 R&D Projects: GA MŠk(CZ) EE2.4.31.0056; GA MŠk(CZ) EE2.3.20.0248; GA MŠk(CZ) EE2.3.20.0265; GA ČR GA13-04291S Institutional support: RVO:67179843 Keywords : Central Europe * crown condition * precipitation * sessile oak * temperature * tree rings Subject RIV: GK - Forestry Impact factor: 0.723, year: 2014

Grazing preference and utilization of soil fungi by Folsomia candida (Collembola)

Science.gov (United States)

Hedenec, Petr; Frouz, Jan

2016-04-01

Soil fungi are important food resources for soil fauna. Here we ask whether the collembolan Folsomia candida shows selectivity in grazing between four saprophytic fungi (Penicillium chrysogenum, Penicillium expansum, Absidia glauca, and Cladosporium herbarum), whether grazing preference corresponds to effects on collembolan reproduction, and whether the effects of fungi on grazing and reproduction depends on the fungal substrate, which included three kinds of litter (Alnus glutinosa, Salix caprea, and Quercus robur) and one kind of agar (yeast extract). On agar, Cladosporium herbarum and Absidia glauca were the most preferred fungi and supported the highest collembolan reproduction. On fungal-colonized litter, grazing preference was more affected by litter type than by fungal species whereas collembolan reproduction was affected by both litter type and fungal species. On fungal-colonized litter, the litter type that was most preferred for grazing did not support the highest reproduction, i.e., there was an inconsistency between food preference and suitability. Alder and willow were preferred over oak for grazing, but alder supported the least reproduction.

Tree species effect on the redistribution of soil metals

International Nuclear Information System (INIS)

Mertens, Jan; Van Nevel, Lotte; De Schrijver, An; Piesschaert, Frederic; Oosterbaan, Anne; Tack, Filip M.G.; Verheyen, Kris

2007-01-01

Phytostabilization of metals using trees is often promoted although the influence of different tree species on the mobilization of metals is not yet clear. Soil and biomass were sampled 33 years after planting four tree species (Quercus robur, Fraxinus excelsior, Acer pseudoplatanus, Populus 'Robusta') in a plot experiment on dredged sediment. Poplar took up high amounts of Cd and Zn and this was associated with increased Cd and Zn concentrations in the upper soil layer. The other species contained normal concentrations of Cd, Cu, Cr, Pb and Zn in their tissues. Oak acidified the soil more than the other species and caused a decrease in the concentration of metals in the upper soil layer. The pH under poplar was lower than expected and associated with high carbon concentrations in the top soil. This might be assigned to retardation of the litter decomposition due to elevated Cd and Zn concentrations in the litter. - Trees (33-year-old) growing on polluted dredged sediment have influenced the metal concentration in the upper soil layer and there was a significant tree species effect

Factors affecting soil fauna feeding activity in a fragmented lowland temperate deciduous woodland.

Science.gov (United States)

Simpson, Jake E; Slade, Eleanor; Riutta, Terhi; Taylor, Michele E

2012-01-01

British temperate broadleaf woodlands have been widely fragmented since the advent of modern agriculture and development. As a result, a higher proportion of woodland area is now subject to edge effects which can alter the efficiency of ecosystem functions. These areas are particularly sensitive to drought. Decomposition of detritus and nutrient cycling are driven by soil microbe and fauna coactivity. The bait lamina assay was used to assess soil fauna trophic activity in the upper soil horizons at five sites in Wytham Woods, Oxfordshire: two edge, two intermediate and one core site. Faunal trophic activity was highest in the core of the woodland, and lowest at the edge, which was correlated with a decreasing soil moisture gradient. The efficiency of the assay was tested using four different bait flavours: standardised, ash (Fraxinus excelsior L.), oak (Quercus robur L.), and sycamore (Acer pseudoplatanus L.). The standardised bait proved the most efficient flavour in terms of feeding activity. This study suggests that decomposition and nutrient cycling may be compromised in many of the UK's small, fragmented woodlands in the event of drought or climate change.

Variability in morphology of Microsphaera alphitoides Griffon et Maubl. in Poland

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Krzysztof Ufnalski

2011-01-01

Full Text Available The aim of this study was to verify descriptions of the morphology of the fungus responsible for powdery mildew on oak leaves of nursery seedlings and of young trees in forest stands. Infected, fully developed leaves from apical parts of stems of Quercus robur or Q. petraea were collected in two national parks and in six forest districts in Poland. The taxonomic characteres of all specimens were generally consistent with those given in keys for Microsphaera alphitoides. However, the limoniform shape of conidia, characteristic of two sites (nurseries, has not been found in available synopses. Limoniform conidia were significantly longer and wider than others. Agreat variety of forms of mycelium on leaves were observed. The mycelium appeared in three forms: (1 floccose or felted oval patches (always with yellow or brown discoloration, (2 faveolate oval patches (often with yellow or brown discoloration, and (3 felted or mealy mycelium along veins (rarely with discoloration. Mycelium without limoniform conidia appeared in all forms, while mycelium with limoniform conidia appeared only in the form of patches, always causing leaf discoloration.

Pollen gene flow, male reproductive success, and genetic correlations among offspring in a northern red oak (Quercus rubra L.) seed orchard

Science.gov (United States)

Lisa Alexander; Keith Woeste

2017-01-01

Northern red oak is a high-value hardwood used for lumber, furniture and veneer. Intensively managed northern red oak seed orchards are required to obtain genetic gain for trait improvement. Data from conifer seed orchards and natural and managed stands of hardwood trees have shed light on the distance over which pollen can move, and underscore the need for managerial...

Analytical approaches to the determination of simple biophenols in forest trees such as Acer (maple), Betula (birch), Coniferus, Eucalyptus, Juniperus (cedar), Picea (spruce) and Quercus (oak).

Science.gov (United States)

Bedgood, Danny R; Bishop, Andrea G; Prenzler, Paul D; Robards, Kevin

2005-06-01

Analytical methods are reviewed for the determination of simple biophenols in forest trees such as Acer (maple), Betula (birch), Coniferus, Eucalyptus, Juniperus (cedar), Picea (spruce) and Quercus (oak). Data are limited but nevertheless clearly establish the critical importance of sample preparation and pre-treatment in the analysis. For example, drying methods invariably reduce the recovery of biophenols and this is illustrated by data for birch leaves where flavonoid glycosides were determined as 12.3 +/- 0.44 mg g(-1) in fresh leaves but 9.7 +/- 0.35 mg g(-1) in air-dried samples (data expressed as dry weight). Diverse sample handling procedures have been employed for recovery of biophenols. The range of biophenols and diversity of sample types precludes general procedural recommendations. Caution is necessary in selecting appropriate procedures as the high reactivity of these compounds complicates their analysis. Moreover, our experience suggests that their reactivity is very dependent on the matrix. The actual measurement is less contentious and high performance separation methods particularly liquid chromatography dominate analyses whilst coupled techniques involving electrospray ionization are becoming routine particularly for qualitative applications. Quantitative data are still the exception and are summarized for representative species that dominate the forest canopy of various habitats. Reported concentrations for simple phenols range from trace level (<0.1 microg g(-1)) to in excess of 500 microg g(-1) depending on a range of factors. Plant tissue is one of these variables but various biotic and abiotic processes such as stress are also important considerations.

Dynamics of forest populations in the mountain resort region of the North Caucasus

Science.gov (United States)

Chalaya, Elena; Efimenko, Natalia; Slepykh, Olga; Slepykh, Viktor; Povolotskaya, Nina

2017-04-01

Prehistoric formula of forest species composition of the resort region Caucasian Mineralnye Vody (RR CMV) in the North Caucasus is 6Q3Cb1Fe [1]. According to it, undisturbed forests of the region consisted of the pedunculate oak (Quercus robur L.) and the durmast (Quercus cerris L.) by 60%, the European hornbeam (Carpinus betulus L.) by 30% and the European ash (Fraxinus excelsior L.) only by 10%. At present the formula of forest composition of the region is 5Fe3Cb2Q, according to it, the rate of oak-groves (the most valuable to resort landscape gardening) has reduced to 20%, and the ash-tree, though the rate of the hornbeam has not changed, increased up to 50%. Forest breeding populations in the RR CMV are referred to natural medical resources as they have high rehabilitation and climate-regulating properties, the change in forest breeding populations influences the conditions of the resort climate-landscape-therapy. The researches conducted in the perfect oak wood of vegetative origin in Beshtaugorsky Forestry Area (BFA) of the RR CMV have shown the reduction of the pedunculate oak in the tree-stand composition during 1984-2014 from 10 to 8 units in the composition: the European ash (1 unit) and the crataegus monogyna (Crataegus monogyna Jacq.), the checker tree (Sorbus torminalis (L.) Crantz), the common pear (Pyrus communis L.) have appeared [2]. The rate of the pedunculate oak decreased from 10 units to 9 in the perfect planting of the pedunculate oak of the artificial origin (Mashuk section of the forestry of BFA of the RR CMV) during 1986-2016. Among accompanying breeds there was the English field maple (Acer campestre L.), the Chinese elm in singular (Ulmus parvifolia Jacq.), the single-seed hawthorn. The reliable regrowth (4C3Fe3Ac+Q+Cm+Pc+Up) in number of 3,9 thousand pieces/hectare defines the perspective of complete replacement of the oak crop in the future on planting with dominance of the hornbeam and the involvement of the ash-tree and the English

Identification of fungal plant pathogens associated with oak (Quercus humboldtii Bonpl.), In the municipalities of Encino (Santander), Arcabuco, and Tipacoque (Boyaca)

International Nuclear Information System (INIS)

Monroy Castro, Leidi Yunari; Lizarazo Forero, Luz Marina

2010-01-01

The objectives of this study were to isolate and determine the presence of the pathogen Phytophthora ramorum and other potential pathogens of Quercus humboldtii, and evaluate the possibility of using the antagonistic capacity of bacteria isolated from rhizosphere and phyllosphere against them. The study was conducted in the conservation corridor Guantiva - La Rusia - Iguaque, in the municipalities of Encino (Santander), Arcabuco and Tipacoque (Boyaca). The phytopathogenic fungi were isolated using direct seeding of leaves with symptoms of fungal infection in OGY, Sabouraud, and PDA + Lactic acid at 0.2%. We used the plate counting technique for the isolation of bacteria from rhizospheric and bulk soil. Phytophthora ramorum was not isolated, but phytopathogenic fungi of the genus Fusarium spp., and Pestalotia spp., were obtained in the isolates. Microbial populations of rhizospheric and bulk soil were scarce, exhibited low diversity, and were dominated by few morphotypes. We identified four species of bacteria: Pseudomonas fluorescens, Bacillus macerans, Pinus sylvestris and Staphylococcus epidermidis. The phyllosphere community was dominated by Pseudomonas fluorescens. The species Pseudomonas fluorescens and Pinus sylvestris did not exhibited antagonistic properties against Pestalotia spp. Further studies are required to confirm Fusarium spp., and Pestalotia spp., pathogenic activity against Quercus humboldtii.

Analysis of landscape patterns and their relationship with oak (Quercus Humboldtii Bonpl.) regeneration in the municipality of Popayan, Cauca

International Nuclear Information System (INIS)

Cabezas Gaviria Alexander; Ospina Montealegre Roman

2010-01-01

Landscape patterns were determined for three different areas having oak populations in the Popayan municipality (Clarete, Rejoya and Pisoje). Two Landsat images from different years and polygons with areas equal or greater than 1.5 hectares were used for land use classification. Patch Analysis software was used in order to determine quantitative variables. Structure description included: number of patches, mean patch size, mean patch index, mean patch fractal dimension and mean perimeter-area ratio. Dispersion and fragmentation were evaluated with the three indexes: Mean Nearest Neighbor Distance, Mean Proximity Index and Interspersion Juxtaposition Index. Community variables included: basal area, terrain slope, light percentage and regeneration density, and were measured in an area of 3600 m2 for each landscape. Landscape and community information were analyzed using principal component analysis (PCA). The first two components explained 91.4% of data variability; they were determined mostly by landscape variables than community factors. Correlation analysis and the Kruskal-Wallis test showed that the variable of major importance regarding oak tree regeneration were the Neighbor Distance in secondary forest patches, the Mean Proximity Index in oak tree forest patches and the Juxtaposition Index in patches of planted forests.

Using aerial photography to estimate wood suitable for charcoal in managed oak forests

Science.gov (United States)

Ramírez-Mejía, D.; Gómez-Tagle, A.; Ghilardi, A.

2018-02-01

Mexican oak forests (genus Quercus) are frequently used for traditional charcoal production. Appropriate management programs are needed to ensure their long-term use, while conserving the biodiversity and ecosystem services, and associated benefits. A key variable needed to design these programs is the spatial distribution of standing woody biomass. A state-of-the-art methodology using small format aerial photographs was developed to estimate the total aboveground biomass (AGB) and aboveground woody biomass suitable for charcoal making (WSC) in intensively managed oak forests. We used tree crown area (CAap) measurements from very high-resolution (30 cm) orthorectified small format digital aerial photographs as the predictive variable. The CAap accuracy was validated using field measurements of the crown area (CAf). Allometric relationships between: (a) CAap versus AGB, and (b) CAap versus WSC had a high significance level (R 2 > 0.91, p < 0.0001). This approach shows that it is possible to obtain sound biomass estimates as a function of the crown area derived from digital small format aerial photographs.

Characterization of the cork oak transcriptome dynamics during acorn development.

Science.gov (United States)

Miguel, Andreia; de Vega-Bartol, José; Marum, Liliana; Chaves, Inês; Santo, Tatiana; Leitão, José; Varela, Maria Carolina; Miguel, Célia M

2015-06-25

Cork oak (Quercus suber L.) has a natural distribution across western Mediterranean regions and is a keystone forest tree species in these ecosystems. The fruiting phase is especially critical for its regeneration but the molecular mechanisms underlying the biochemical and physiological changes during cork oak acorn development are poorly understood. In this study, the transcriptome of the cork oak acorn, including the seed, was characterized in five stages of development, from early development to acorn maturation, to identify the dominant processes in each stage and reveal transcripts with important functions in gene expression regulation and response to water. A total of 80,357 expressed sequence tags (ESTs) were de novo assembled from RNA-Seq libraries representative of the several acorn developmental stages. Approximately 7.6 % of the total number of transcripts present in Q. suber transcriptome was identified as acorn specific. The analysis of expression profiles during development returned 2,285 differentially expressed (DE) transcripts, which were clustered into six groups. The stage of development corresponding to the mature acorn exhibited an expression profile markedly different from other stages. Approximately 22 % of the DE transcripts putatively code for transcription factors (TF) or transcriptional regulators, and were found almost equally distributed among the several expression profile clusters, highlighting their major roles in controlling the whole developmental process. On the other hand, carbohydrate metabolism, the biological pathway most represented during acorn development, was especially prevalent in mid to late stages as evidenced by enrichment analysis. We further show that genes related to response to water, water deprivation and transport were mostly represented during the early (S2) and the last stage (S8) of acorn development, when tolerance to water desiccation is possibly critical for acorn viability. To our knowledge this work

The influence of season on carbon allocation to suberin and other stem components of cork oak saplings.

Science.gov (United States)

Aguado, Pedro L; Curt, M Dolores; Pereira, Helena; Fernández, Jesús

2017-02-01

The growth pattern of cork oak (Quercus suber L.), an important component of South Mediterranean woodlands, is seasonal. Seasonality has been found for shoot, radial and cork ring growth as well as for carbon (C) photoassimilation, nutrients remobilization and water relations, among other physiological aspects. However, little is known about the seasonality of C allocation to cork oak chemical compounds, including suberin, a major component of cork. In order to achieve this goal, an isotopic tracer experiment was conducted using 18-month-old cork oaks so that the fate of C photoassimilated in different seasons could be traced into biochemical (main organic) stem components. Two distinct patterns of C allocation, associated with the stages of active plant growth and dormancy, were identified and described. Evidence was provided that translocation of photoassimilated C to stems does not cease during the dormancy period and that suberin is the major C sink for the C assimilated throughout the whole active growth period, as compared with other stem components. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Desenvolupament d'una tècnica d'empelt de surera ("Quercus suber L.") sobre alzina ("Quercus ilex L.")

OpenAIRE

PERIS RODRIGO, JOSEP ENRIC

2013-01-01

El Trabajo Final de Carrera trata principalmente de buscar la técnica de injerto que más se ajuste para realizar injertos de alcornoque (Quercus suber L.) sobre encina (Quercus ilex L.). Para ello se han probado diferentes técnicas de injerto realizadas en diferentes épocas del año, en condiciones ambientales de exterior y en condiciones de invernadero, utilizando material vegetal de alcornoque adulto y juvenil. Con ello se persigue determinar qué técnica de injerto ofrece mejores resultados ...

Estimation of soil respiration using automated chamber systems in an oak (Quercus mongolica) forest at the Nam-San site in Seoul, Korea.

Science.gov (United States)

Joo, Seung Jin; Park, Soon-Ung; Park, Moon-Soo; Lee, Chang Seok

2012-02-01

Soil respiration (R(soil)) is the largest component of ecosystem respiration produced by the autotrophic and heterotrophic respirations. Its variability on multiple time scales strongly depends on environmental variables such as temperature and moisture. To investigate the temporal variations of R(soil) in a cool-temperate oak (Quercus mongolica) forest at the Nam-San site in Seoul, Korea, continuous measurements of R(soil) using the automated chamber systems, air and soil temperatures and soil moisture are made for the period from April 2010 to March 2011. The observed data indicate that the R(soil) shows a remarkable seasonal variation in accordance with temperatures with high in summer and low in winter. The R(soil) is found to be strongly correlated with soil temperature (T(s)) at the 5cm depth throughout the year. However, the high fluctuation of R(soil) is found to be related with soil moisture content (M(s)) during the forest growing season. The estimated annual Q(10) value using the 1.5m-high air temperature is found to be 2.4 that is comparable with other studies in temperate forest ecosystems. The optimal regression equation of R(soil) with the T(s) at 5cm depth and the M(s) at 15cm depth is found to be R(soil)=124.3 exp (0.097T(s))-55.3 (M(s))(2)+2931.9 (M(s))-38516 for T(s)≥0°C and R(soil)=0 for T(s)soil). The annual total soil respiration estimated by the optimal regression equation is found to be 1264gCm(-2) with a maximum of 685gCm(-2) in the summer season and a minimum of 33gCm(-2) in the winter season. The present study can be implemented for the determination of the carbon balance of a cool-temperate Q. mongolica forest with the provision of photosynthesis. Copyright © 2011 Elsevier B.V. All rights reserved.

The healing effect of combined hydroalcoholic extract of Teocurium polium and the seed hull of Quercus brantii on burn wounds in rats

Directory of Open Access Journals (Sweden)

Mohammadi Jamshid

2016-10-01

Full Text Available Plants and their extracts have considerable potential for wound healing. So, The aim of this study was to evaluate the wound healing effect of combined hydroalcoholic extract of Teocurium Polium (TP and the seed hull of Quercus brantii (Persian oak (QB and comparing with silver sulfadiazine (SSD ointment (1% in rats. Animals were divided into six groups consist of normal (untreated, physiologic serum, TP, seed hulls of Quercus brantii (QB, combination of TP and QB and the other group was SSD. Burn area size, epidermal and dermal diameter, number of hair follicle, histopathology of the burn skin and concentration of plasma malondialdehide (MDA were determined in different groups. Animals treated with QB and TP, SSD and combination of two extracts (QB +TP showed a significant reduction in the burn area. Serum MDA decreased significantly in animals treated with QB, TP and QB+TP. Histological comparison has shown that TP, QB and combination of them significantly increased reepithelialization in burn wounds, as compared to normal group. In conclusion, our results demonstrated that topical application of TP and QB has a significant effect on the burn wound healing.

Ectomycorrhizal fungal diversity and community structure associated with cork oak in different landscapes.

Science.gov (United States)

Reis, Francisca; Valdiviesso, Teresa; Varela, Carolina; Tavares, Rui M; Baptista, Paula; Lino-Neto, Teresa

2018-05-01

Cork oak (Quercus suber L.) forests play an important ecological and economic role. Ectomycorrhizal fungi (ECMF) are key components for the sustainability and functioning of these ecosystems. The community structure and composition of ECMF associated with Q. suber in different landscapes of distinct Mediterranean bioclimate regions have not previously been compared. In this work, soil samples from cork oak forests residing in different bioclimates (arid, semi-arid, sub-humid, and humid) were collected and surveyed for ectomycorrhizal (ECM) root tips. A global analysis performed on 3565 ECM root tips revealed that the ECMF community is highly enriched in Russula, Tomentella, and Cenoccocum, which correspond to the ECMF genera that mainly contribute to community differences. The ECMF communities from the rainiest and the driest cork oak forests were distinct, with soils from the rainiest climates being more heterogeneous than those from the driest climates. The analyses of several abiotic factors on the ECMF communities revealed that bioclimate, precipitation, soil texture, and forest management strongly influenced ECMF structure. Shifts in ECMF with different hyphal exploration types were also detected among forests, with precipitation, forest system, and soil texture being the main drivers controlling their composition. Understanding the effects of environmental factors on the structuring of ECM communities could be the first step for promoting the sustainability of this threatened ecosystem.

Analysis of the expression of putative heat-stress related genes in relation to thermotolerance of cork oak.

Science.gov (United States)

Correia, Barbara; Rodriguez, José Luis; Valledor, Luis; Almeida, Tânia; Santos, Conceição; Cañal, Maria Jesús; Pinto, Glória

2014-03-15

Cork oak (Quercus suber L.) is a research priority in the Mediterranean area and because of cork oaks' distribution these stands are experiencing daily stress. Based on projections of intensifying climate change and considering the key role of exploring the recovery abilities, cork oak seedlings were subjected to a cumulative temperature increase from 25°C to 55°C and subsequent recovery. CO2 assimilation rate, chlorophyll fluorescence, anthocyanins, proline and lipid peroxidation were used to evaluate plant performance, while the relative abundance of seven genes encoding for proteins of cork oak with a putative role in thermal/stress regulation (POX1, POX2, HSP10.4, HSP17a.22, CHS, MTL and RBC) was analyzed by qPCR (quantitative Polymerase Chain Reaction). A temperature change to 35°C showed abundance alterations in the tested genes; at 45°C, the molecular changes were associated with an antioxidant response, possibly modulated by anthocyanins. At 55°C, HSP17a.22, MTL and proline accumulation were evident. After recovery, physiological balance was restored, whereas POX1, HSP10.4 and MTL abundances were suggested to be involved in increased thermotolerance. The data presented here are expected to pinpoint some pathways changes occurring during such stress and further recovery in this particular Mediterranean species. Copyright © 2013 Elsevier GmbH. All rights reserved.

Approaches to restoration of oak forests on farmed lowlands of the Mississippi river and its tributaries (Avances en la restauración de bosques de roble en tierras bajas agrícolas del Río Mississippi y sus tributaries)

Science.gov (United States)

E.S. Gardiner; D.C. Dey; John Stanturf; B.R. Lockhart

2010-01-01

The lowlands associated with the Mississippi River and its tributaries historically supported extensive broadleaf forests that were particularly rich in oak (Quercus spp.) species. Beginning in the 1700s, deforestation for agriculture substantially reduced the extent of the original forest, and fragmented the remainder into small parcels. More recently, declines in...

Recent growth coherence in long-term oak (Quercus spp.) ring width chronologies in the Czech Republic

Czech Academy of Sciences Publication Activity Database

Dobrovolný, Petr; Rybníček, Michal; Büntgen, Ulf; Trnka, Miroslav; Brázdil, Rudolf; Stachoň, Z.; Prokop, O.; Kolář, Tomáš

2016-01-01

Roč. 70, 2-3 (2016), s. 133-141 ISSN 0936-577X R&D Projects: GA MŠk(CZ) LO1415; GA ČR GA13-04291S; GA MŠk(CZ) EE2.3.20.0248 Institutional support: RVO:67179843 Keywords : Tree-ring width chronology * Oak species * Tree-age structure * Site-specific conditions * Hydroclimate sensitivity * Czech Republic Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.578, year: 2016

Recommended Species for Vegetative Stabilization of Training Lands in Arid and Semi-Arid Environments

Science.gov (United States)

1985-09-01

bitterbrush Purshia glandulosa Apache plume Fallugia paradoxa Arizona fesce Festuca arizonica Ashe juniper Juniperus ashei Australian saltbush Atriplex...elm Ulmus crassifolia *Cheatgrass Bromus tectorum -Chinkapin oak Quercus muhlenbergii Cholla Opuntia, spp. * Cicer milkvetch Astragalus cicer Clovers...Linum lewisii Little bluestem Schizachyrium scoparium *Littleleaf palo verde Cercidium microphyllum *Live oak Quercus virginiana Lovegrasses Eragrostis

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

The influence of chemical characteristics of precipitation on tree health in Banjica Forest (Belgrade, Serbia

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Radovanović M.

2012-01-01

Full Text Available The most represented tree species in the Banjica Forest are Acer negundo, Quercus robur, Acer pseudoplatanus, Populus nigra, Fraxinus pennsylvanica, Fraxinus ornus and Robinia pseudoacacia. According to the ICP Forests combined assessment (degree of defoliation and decolorization, endangered species are Populus nigra (64.3% of heavily damaged trees, Quercus robur (45.5%, Fraxinus pennsylvanica (37.0% and Acer negundo (26.6%, while the situation is much better for Acer pseudoplatanus and Fraxinus ornus. For Robinia pseudoacacia, 83% of trees are without decolorization, however, defoliation is established. In the period from April to October 2009, the average pH of rainwater was 5.46, and 5.18 in the period from November 2009 to March 2010. The concentration of SO42- in the period from April to October 2009 amounted to an average of 24.21 mg/l, and 28.87 mg/l in the period from November 2009 to March 2010. The concentration of SO42- and pH values is a possible explanation for the condition of the trees. [Acknowledgments. The results are a part of the project III47007 funded by the Ministry of Education and Science of the Republic of Serbia.

Monitoring drought impact on Mediterranean oak savanna vegetation using remote sensing

Science.gov (United States)

González-Dugo, Maria P.; Carpintero, Elisabet; Andreu, Ana

2015-04-01

A holm oak savanna, known as dehesa in Spain and montado in Portugal, is the largest agroforest ecosystem in Europe, covering about 3 million hectares in the Iberian Peninsula and Greece (Papanastasis et al., 2004). It is considered an example of sustainable land use, supporting a large number of species and diversity of habitats and for its importance in rural development and economy (Plieninger et al., 2001). It is a combination between an agricultural and a naturally vegetated ecosystem, consisting of widely-spaced oak trees (mostly Quercus Ilex and Quercus suber) combined with a sub-canopy composed by crops, annual grassland and/or shrubs. It has a Mediterranean climate with severe periodic droughts. In the last decades, this system is being exposed to multiple threats derived from socio-economic changes and intensive agricultural use, which have caused environmental degradation, including tree decline, changes in soil properties and hydrological processes, and an increase of soil erosion (Coelho et al., 2004). Soil water dynamics plays a central role in the current decline and reduction of forested areas that jeopardizes the preservation of the system. In this work, a series of remotely sensed images since 1990 to present was used to evaluate the effect of several drought events occurred in the study area (1995, 2009, 2010/2011) on the tree density and water status. Data from satellites Landsat and field measurements have been combined in a spectral mixture model to assess separately the evolution of tree, dry grass and bare soil ground coverage. Only summer images have been used to avoid the influence of the green herbaceous layer on the analysis. Thermal data from the same sensors and meteorological information are integrated in a two source surface energy balance model to compute the Evaporative Stress Index (ESI) and evaluate the vegetation water status. The results have provided insights about the severity of each event and the spatial distribution of

Climate effects on cork growth in Cork oak plantations in Sicily (Italy

Directory of Open Access Journals (Sweden)

2009-03-01

Full Text Available Cork oak (Quercus suber L. is usually dominant in silvopastoral systems in many areas of Sicily, where the trees are debarked periodically for cork production. In spite of the importance of cork and cork oak stands in Sicilian forests and the potential economic scenarios, few research works have been carried out on these systems. Given the importance of cork thickness in cork quality evaluation, the main objective of this work is to study cork growth in cork oak productive stands spread on the north (Nebrodi Mountains and south-east (Iblei Mountains of Sicily. Image analysis techniques were used on cork surfaces of transverse sections of planks to measure cork rings. Dendrochronological analysis was applied to study annual fluctuation on rings growth in relation to various climate parameters in a cork cycle production. Results showed that rainfall, summer drought and temperature are determining factors in controlling cork growth. In siliceous areas of Nebrodi Mountains correlation between cork growth index and rainfall indicates that the rain period from May to September strongly influences phellogen activity. Temperature and water stress indices, on the other hand, show a negative correlation with cork growth. In clay and evolved soils of volcanic plateau of Iblei Mountains January precipitation shows a positive correlation with cork growth index. Also absolute minimum temperature in June and absolute maximum temperature in September show a positive correlation when temperature possibly has influence on phellogen activity during growing season.

First record of the oak gall wasp genus Neuroterus Hartig, 1840 (Hymenoptera, Cynipidae, Cynipini from Central America with description of three new species from Panama and Costa Rica

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E. Medianero

2017-05-01

Full Text Available Three new species of Neuroterus Hartig, 1840 (Hymenoptera: Cynipidae: Cynipini are described from Panama and Costa Rica: Neuroterus elvisi sp. n., Neuroterus pulchrigalla sp. n., and Neuroterus glandiphilus sp. n. The new species are the first of the genus Neuroterus recorded from Central America and the Neotropical region. The new species induce galls on Quercus bumelioides Liebm. (Fagaceae, sect. Quercus, White Oaks. Additional evidence of the presence of other unidentified species of Neuroterus in the sampled area is presented. Diagnostic morphological characters, gall descriptions, distributions, host plant and other biological data of the new species are given and discussed. http://urn:lsid:zoobank.org:pub:48D0C1E1-1D0C-40D8-B890-FFC85AE7A213

The importance of drought-pathogen interactions in driving oak mortality events in the Ozark Border Region

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Wood, Jeffrey D.; Knapp, Benjamin O.; Muzika, Rose-Marie; Stambaugh, Michael C.; Gu, Lianhong

2018-01-01

Forests are expected to become more vulnerable to drought-induced tree mortality owing to rising temperatures and changing precipitation patterns that amplify drought lethality. There is a crucial knowledge gap regarding drought-pathogen interactions and their effects on tree mortality. The objectives of this research were to examine whether stand dynamics and ‘background’ mortality rates were affected by a severe drought in 2012; and to evaluate the importance of drought-pathogen interactions within the context of a mortality event that killed 10.0% and 26.5% of white (Quercus alba L.) and black (Q. velutina Lam.) oak stems, respectively, in a single year. We synthesized (i) forest inventory data (24 years), (ii) 11 years of ecosystem flux data with supporting biological data including predawn leaf water potential and annual forest inventories, (iii) tree-ring analyses of individual white oaks that were alive and ones that died in 2013, and (iv) documentation of a pathogen infection. This forest displayed stand dynamics consistent with expected patterns of decreasing tree density and increasing basal area. Continued basal area growth outpaced mortality implying a net accumulation of live biomass, which was supported by eddy covariance ecosystem carbon flux observations. Individual white and black oaks that died in 2013 displayed historically lower growth with the majority of dead trees exhibiting Biscogniauxia cankers. Our observations point to the importance of event-based oak mortality and that drought-Biscogniauxia interactions are important in shaping oak stand dynamics in this region. Although forest function has not been significantly impaired, these drought-pathogen interactions could amplify mortality under future climate conditions and thus warrant further investigation.

City of Freeport, Florida, State Road 20 Water Main Installation, Final Environmental Assessment, Eglin Air Force Base, Florida

Science.gov (United States)

2010-07-01

If contamination, drought or natural disaster, such as a hurricane, impacted one water supply, an interconnection with neighboring municipalities...Scientific Name Sandhills Ecological Association Longleaf Pine Pinus palustris Red-cockaded Woodpecker Picoides borealis Turkey Oak Quercus laevis...canadensis Flatwoods Ecological Association Longleaf Pine Pinus palustris Wood Duck Aix sponsa Runner Oak Quercus pumila Red-winged Blackbird Agelaius

Association of genetic and phenotypic variability with geography and climate in three southern California oaks.

Science.gov (United States)

Riordan, Erin C; Gugger, Paul F; Ortego, Joaquín; Smith, Carrie; Gaddis, Keith; Thompson, Pam; Sork, Victoria L

2016-01-01

Geography and climate shape the distribution of organisms, their genotypes, and their phenotypes. To understand historical and future evolutionary and ecological responses to climate, we compared the association of geography and climate of three oak species (Quercus engelmannii, Quercus berberidifolia, and Quercus cornelius-mulleri) in an environmentally heterogeneous region of southern California at three organizational levels: regional species distributions, genetic variation, and phenotypic variation. We identified climatic variables influencing regional distribution patterns using species distribution models (SDMs), and then tested whether those individual variables are important in shaping genetic (microsatellite) and phenotypic (leaf morphology) variation. We estimated the relative contributions of geography and climate using multivariate redundancy analyses (RDA) with variance partitioning. The modeled distribution of each species was influenced by climate differently. Our analysis of genetic variation using RDA identified small but significant associations between genetic variation with climate and geography in Q. engelmannii and Q. cornelius-mulleri, but not in Q. berberidifolia, and climate explained more of the variation. Our analysis of phenotypic variation in Q. engelmannii indicated that climate had more impact than geography, but not in Q. berberidifolia. Throughout our analyses, we did not find a consistent pattern in effects of individual climatic variables. Our comparative analysis illustrates that climate influences tree response at all organizational levels, but the important climate factors vary depending on the level and on the species. Because of these species-specific and level-specific responses, today's sympatric species are unlikely to have similar distributions in the future. © 2016 Botanical Society of America.

THE USE-POTENTIAL OF QUERCUS ALIENA VAR. ACUTESERRATA FOR URBAN PLANTATIONS – BASED ON HABITAT STUDIES IN THE QINLING MOUNTAINS, CHINA

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Henrik SJÖMAN

2015-12-01

Full Text Available Traditionally, a limited number of species and genera dominate the tree stock in streets and urban sites, and recent surveys in European and North American cities show that few species/genera continue to dominate. Yet, over the past decades, a growing proportion of those commonly used species have shown increasing difficulties to cope with urban sites. This has led to considerable and persistent arguments for using a more varied range of trees, including stress-tolerant species, at urban paved sites. This study examined forest systems occurring between 1300-2200 m asl. in the Qinling Mountains, China, in order to evaluate the oriental white oaks (Quercus aliena var. acuteserrata Maximowicz ex Wenzig growth and development in warm and dry forest habitats and hence evaluate its potential for urban paved sites in northern parts of central Europe and in adjoining milder parts of northern Europe. In total, 102 oriental white oak where found in the studied plots and here showed very promising development in habitats experiencing drier conditions than those in park environments in Copenhagen, and is therefore interesting for urban paved sites were the demands of a greater catalogue of tolerant trees are highly needed.

Oak (Quercus spp.) response to climate differs more among sites than among species in central Czech Republic

Czech Academy of Sciences Publication Activity Database

Rybníček, Michal; Čermák, P.; Prokop, O.; Žid, T.; Trnka, Miroslav; Kolář, Tomáš

2016-01-01

Roč. 75, jan (2016), s. 55-65 ISSN 1641-1307 R&D Projects: GA MŠk(CZ) LO1415; GA MŠk(CZ) LD13030; GA MŠk(CZ) EE2.3.20.0265; GA ČR GA13-04291S Institutional support: RVO:67179843 Keywords : Central Europe * oak * precipitation * temperature * tree rings Subject RIV: EH - Ecology, Behaviour Impact factor: 0.776, year: 2016

Diplopimarane, a 20-nor-ent-pimarane produced by the oak pathogen Diplodia quercivora.

Science.gov (United States)

Andolfi, Anna; Maddau, Lucia; Basso, Sara; Linaldeddu, Benedetto T; Cimmino, Alessio; Scanu, Bruno; Deidda, Antonio; Tuzi, Angela; Evidente, Antonio

2014-11-26

In this study a new 20-nor-ent-pimarane, named diplopimarane, was isolated together with sphaeropsidins A (9) and C (10), and (+)-epiepoformin (11) from organic crude extracts of Diplodia quercivora, a recently described oak pathogen originally found on declining Quercus canariensis trees in Tunisia. Diplopimarane was characterized as (1S,2R)-2,8,8-trimethyl-2-vinyl-1,2,3,4,5,6,7,8-octahydrophenanthrene-1,9,10-triol by spectroscopic, X-ray, optical, and chemical methods. It exhibited a wide range of activities including remarkable phytotoxicity on nonhost plants such as tomato cuttings, moderate antifungal activity against important plant pathogens, and moderate zootoxicity against Artemia salina. Its derivatives (2-4 and 6) were also tested for their phytotoxic and zootoxic activities. All these derivatives proved to be active against A. salina at 200 μg/mL, while 2 and 6 were also active on tomato cuttings. The other secondary metabolites (9, 10, and 11) herein reported for D. quercivora exhibited phytotoxic, antifungal, and zootoxic activity. This is the first report on the secondary metabolites secreted in vitro by this oak pathogen that could be key components of its adaptative strategies.

Species-specific Mechanisms Contributing to the Mesophication of Upland Oak Stands in the Absence of Fire

Science.gov (United States)

Babl, E. K.; Alexander, H. D.; Siegert, C. M.; Willis, J. L.; Berry, A. I.

2017-12-01

Upland oak forests of the eastern United States are shifting dominance towards shade-tolerant, fire-intolerant species. This shift is hypothesized to be driven by anthropogenic fire suppression and lead to mesophication, a positive feedback loop where shade-tolerant, fire-sensitive species (i.e. mesophytes) create a cool, moist understory, reducing forest flammability and promoting their own proliferation at the expense of pyrophytic, shade-intolerant species such as oaks. There have been few empirical studies identifying mechanisms of mesophication, and these studies have yet to extensively explore potential mesophytes other than red maple (Acer rubrum). To address this issue, we sampled four hypothesized mesophytes (A. rubrum, A. saccharum, Carya glabra, and Fagus grandifolia) and two upland oak species (Quercus alba and Q. montana) across a gradient of sizes (20-60 cm DBH) in western Kentucky. We quantified canopy, bark, and leaf litter traits among upland oaks and mesophytes that may lead to differences in forest flammability. Preliminary results show that mesophytes had thinner and smoother bark than upland oaks and an increased canopy volume (normalized to stem volume), traits known to influence water movement through the canopy and understory microclimate. Maple leaf litter also decomposed faster, which could decrease fuel loads; after 6 months, red and sugar maple leaf litter lost 37% of original mass compared to 32%, 22%, and 14% mass loss in hickory, oak, and American beech litter, respectively. Furthermore, volumetric soil moisture of the soil organic layer beneath the canopies of mesophytes was 62% moister two days following a rainfall event compared to oaks. These differences in soil organic layer water retention after rainfall could lead to fuel discontinuity. These findings suggest that mesophytes may alter future forest flammability through their bark, canopy, and leaf litter traits which may modify fuel moisture, loads, and continuity and that a

Oak bark allometry and fire survival strategies in the Chihuahuan desert Sky Islands, Texas, USA.

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Schwilk, Dylan W; Gaetani, Maria S; Poulos, Helen M

2013-01-01

Trees may survive fire through persistence of above or below ground structures. Investment in bark aids in above-ground survival while investment in carbohydrate storage aids in recovery through resprouting and is especially important following above-ground tissue loss. We investigated bark allocation and carbohydrate investment in eight common oak (Quercus) species of Sky Island mountain ranges in west Texas. We hypothesized that relative investment in bark and carbohydrates changes with tree age and with fire regime: We predicted delayed investment in bark (positive allometry) and early investment in carbohydrates (negative allometry) under lower frequency, high severity fire regimes found in wetter microclimates. Common oaks of the Texas Trans-Pecos region (Quercus emoryi, Q. gambelii, Q. gravesii, Q. grisea, Q. hypoleucoides, Q. muehlenbergii, and Q. pungens) were sampled in three mountain ranges with historically mixed fire regimes: the Chisos Mountains, the Davis Mountains and the Guadalupe Mountains. Bark thickness was measured on individuals representing the full span of sizes found. Carbohydrate concentration in taproots was measured after initial leaf flush. Bark thickness was compared to bole diameter and allometries were analyzed using major axis regression on log-transformed measurements. We found that bark allocation strategies varied among species that can co-occur but have different habitat preferences. Investment patterns in bark were related to soil moisture preference and drought tolerance and, by proxy, to expected fire regime. Dry site species had shallower allometries with allometric coefficients ranging from less than one (negative allometry) to near one (isometric investment). Wet site species, on the other hand, had larger allometric coefficients, indicating delayed investment to defense. Contrary to our expectation, root carbohydrate concentrations were similar across all species and sizes, suggesting that any differences in below ground

Oak bark allometry and fire survival strategies in the Chihuahuan desert Sky Islands, Texas, USA.

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Dylan W Schwilk

Full Text Available Trees may survive fire through persistence of above or below ground structures. Investment in bark aids in above-ground survival while investment in carbohydrate storage aids in recovery through resprouting and is especially important following above-ground tissue loss. We investigated bark allocation and carbohydrate investment in eight common oak (Quercus species of Sky Island mountain ranges in west Texas. We hypothesized that relative investment in bark and carbohydrates changes with tree age and with fire regime: We predicted delayed investment in bark (positive allometry and early investment in carbohydrates (negative allometry under lower frequency, high severity fire regimes found in wetter microclimates. Common oaks of the Texas Trans-Pecos region (Quercus emoryi, Q. gambelii, Q. gravesii, Q. grisea, Q. hypoleucoides, Q. muehlenbergii, and Q. pungens were sampled in three mountain ranges with historically mixed fire regimes: the Chisos Mountains, the Davis Mountains and the Guadalupe Mountains. Bark thickness was measured on individuals representing the full span of sizes found. Carbohydrate concentration in taproots was measured after initial leaf flush. Bark thickness was compared to bole diameter and allometries were analyzed using major axis regression on log-transformed measurements. We found that bark allocation strategies varied among species that can co-occur but have different habitat preferences. Investment patterns in bark were related to soil moisture preference and drought tolerance and, by proxy, to expected fire regime. Dry site species had shallower allometries with allometric coefficients ranging from less than one (negative allometry to near one (isometric investment. Wet site species, on the other hand, had larger allometric coefficients, indicating delayed investment to defense. Contrary to our expectation, root carbohydrate concentrations were similar across all species and sizes, suggesting that any differences in

Large-scale patterns of Quercus ilex, Quercus suber, and Quercus pyrenaica regeneration in central-western Spain

DEFF Research Database (Denmark)

Plieninger, Tobias; Rolo, Víctor; Moreno, Gerardo