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Showing 1 to 20 of 80 for “"Douglas fir"”.
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Effects of Thermomechanical Refining on Douglas fir Wood
… In cooperation with a North American MDF Douglas fir plant, two refining energies were used to produce resin and additive-free fibers. Refining reduced fiber dimensions and increased bulk density, more so at the highest energy. Thermoporosimetry showed increases in sub-micron scale …
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Role of mycorrhizal networks in dry Douglas-fir forests
… for interplant resource transfer. Interior Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) is an obligate ectomycorrhizal (EM) tree species that has high potential to form MNs with neighboring trees because of its receptivity to a diverse community of EM fungi. This MN …
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Extractives of Douglas-fir and Their Impacts for Biofuel Saccharification
… treetops, and other unmerchantable timber. Douglas-fir residues have received special attention since Douglas-fir is the most abundant tree in the timberlands of the Western United States. Biofuel from this material has yet to hit full-scale production, but production processes are already …
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Activation energy of Douglas fir char gasification by carbon dioxide
The activation energy of Douglas fir wood char gasified in carbon dioxide was determined. Activation energies were found for chars that had been pyrolyzed in nitrogen at 600, 750, and 900°C. A thermogravimetric analyzer provided the weight versus temperature data used to obtain the activation …
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Seedborne fusarium and root colonization of container-grown douglas-fir seedlings
… Fusarium in root colonization of container-grown Douglas-fir seedlings was studied in two coastal Douglas-fir seedlots; one contaminated with Fusarium and the other with minimal Fusarium. Seedlots were treated using either a standing water imbibition, or a running water imbibition with a …
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Investigating Differences in Douglas-fir and Southern Yellow Pine Bonding Properties
… yellow pine (represented by Pinus taeda) and Douglas-fir (Pseudotsuga menziesii) mature and juvenile wood were examined in terms of density, chemical composition, surface energy, shear stress, % wood failure, and delamination. Density was measured using a QTRS density scanner. Loblolly pine …
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Family x site interaction in a progeny test of coastal Douglas-fir
Genotype x environment interaction in coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) was evaluated for height at the 6th-, 7'11- and 124'. year and diameterat the 12th. year. Data collected from 15 families of the Experimental Project 708 of the BCMF were used. In …
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Genetic variability in Douglas-fir based on molecular genetic markers and morphological traits
Genetic variability in Douglas-fir (Pseudotsuga menziesii (Mirb) Franco) in British Columbia was assessed both by analyzing molecular genetic markers at the population level and by evaluation of quantitative traits in parent trees. Genetic variability in the natural populations of Douglas-fir in …
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Free living nitrogen-fixation in ponderosa pine/Douglas-fir forests in western Montana
… ecosystems is required to minimize N losses to fire, harvesting, and other forms of land management. The influence of fire, fire exclusion and forest restoration treatments on non-symbiotic N-fixation in the forest ecosystem has been poorly studied. Over the past 100 years, fire has been greatly …
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Free living nitrogen-fixation in ponderosa pine/Douglas-fir forests in western Montana
… ecosystems is required to minimize N losses to fire, harvesting, and other forms of land management. The influence of fire, fire exclusion and forest restoration treatments on non-symbiotic N-fixation in the forest ecosystem has been poorly studied. Over the past 100 years, fire has been greatly …
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Effects of Biotic Interactions on Climate-Growth Relationships of Douglas-Fir and Ponderosa Pine
<p>Plant processes depend on the interplay between intrinsic characteristics (e.g., photosynthetic capacity) and external variables, such as light, temperature and water availability. However, these factors are often tightly interconnected and vary significantly among species with different life …
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Effects of Biotic Interactions on Climate-Growth Relationships of Douglas-Fir and Ponderosa Pine
<p>Plant processes depend on the interplay between intrinsic characteristics (e.g., photosynthetic capacity) and external variables, such as light, temperature and water availability. However, these factors are often tightly interconnected and vary significantly among species with different life …
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Dwarf Mistletoe And Its Effect Upon The Growth Of Larch And Douglas Fir In Western Montana
… Arceuthobium pussillum, A. americanum, A, douglasii, A. vaginatum, and A. campylopodum have been recognized in North America. All of them are restricted to coniferous hosts. The aerial portions of the plant are small, not exceeding 2 1/2 inches in length, and constrain very little …
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Mycorrhizal fungus communities of Douglas-fir (Pseudotsuga menziesii) seedlings and trees: effects of proximity to residual trees
The influence of mature Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees in partially harvested stands on seedling growth and colonization by ectomycorrhizal fungi (EMF) is not well understood. To investigate this, Douglas-fir seedlings were planted near (<6 m) and far (>16 m) from 44- to …
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Laminated root rot: ecology relationship and stand productivity impacts in coastal Douglas-fir ecosystems of British Columbia
… (Phellinus) root rot in coastal second growth Douglas-fir ecosystems of southeastern Vancouver Island was investigated in 139 ecosystems centered around 215 growth and yield permanent sample plots (PSP's). The impact of Phellinus root rot on stand productivity was estimated from PSP records and …
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Response of uneven-aged in interior Douglas-fir stands to precommercial thinning in central interior, British Columbia
Proper management of uneven-aged interior Douglas-fir (Pseudotsuga menziesii var. glauca) stands is important for British Columbia’s central and southern interior. These stands constitute one of main components of the operable forest land in these areas, with easy access from main roads and towns. …
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Defining the Regional and Seasonal Climatic Response of Long Douglas-Fir Tree-Ring Chronologies in Central Mexico
… (2007) to document the climate signal of Douglas-fir in central Mexico. Through correlation analysis between five Douglas-fir tree-ring chronologies created by the University of Arkansas-Fayetteville Tree-Ring Laboratory and Zhu and Lettenmaier's (2007) gridded historical climate dataset, …
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