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310 results found
Old-growth coniferous forests differ significantly from young-growth forests in species composition, function (rate and paths of energy flow and nutrient and water cycling), and structure. Most differences can be related to four key structural components of old growth: large live trees, large snags…
Author(s): Jerry F. Franklin, Kermit Jr. Cromack, William Denison, Arthur McKee, Chris Maser, James Sedell, Fred Swanson, Glen Juday
Keywords: Ecosystems, old-growth stands, stand composition, stand structure, Douglas-fir, Pseudotsuga menziesii, western hemlock, Tsuga heterophylla
Source: Gen. Tech. Rep. PNW-GTR-118. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 48 p
Year: 1981
A 51-yr record of observations in stands planted at six spacings, ranging from 4 to 12 ft, illustrates clearly the beneficial effects of wide initial spacing and the detrimental effects of carrying too many trees relative to the size to which they will be grown. Not only are trees larger, but…
Author(s): Donald L. Reukema
Keywords: Plantation spacing (-growth, stand density, stand development, Douglas-fir, Pseudotsuga menziesii
Source: Res. Pap. PNW-RP-253. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 21 p
Year: 1979
This report summarizes the results of lumber recovery studies at four sawmills in western Oregon and western Washington; two dimension mills, one grade mill, and one timber mill were included. Results from individual mills are reported and discussed. The four mills were also combined to approximate…
Author(s): Susan Willits, Thomas D. Fahey
Keywords: Douglas-fir, Pseudotsuga menziesii, lumber recovery, lumber yield, Oregon, Washington
Source: Res. Pap. PNW-RP-400. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 32 p
Year: 1988
Natural regeneration was abundant, regardless of grazing and grass seeding treatments,after shelterwood cutting to three overstory densities (27, 73, and 119 square feet of basal area per acre) in mixed conifer stands in the Starkey Experimental Forest and Range in eastern Oregon. After 6 years,…
Author(s): K.W. Seidel, J. Michael Geist, Gerald S. Strickler
Keywords: Shelterwood cutting method, regeneration (natural), grass, forage, grazing, grand fir, Abies grandis, Douglas-fir, Pseudotsuga menziesii var. glauca, Oregon (eastern)
Source: Res. Pap. PNW-RP-417. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 32 p
Year: 1990
The gravitational component of water potential contributes a standing 0.01 MPa m1 to the xylem tension gradient in plants. In tall trees, this contribution can significantly reduce the water potential near the tree tops. The turgor of cells in buds and leaves is expected to decrease in direct…
Author(s): D.R. Woodruff, B.J. Bond, F.C. Meinzer
Keywords: Pseudotsuga menziesii, Douglas-fir, gravitational component, water potential, height growth, osmotic adjustment, pressure-volume curve, turgor maintenance
Source: Plant, Cell, and Environment. 27: 229-236
Year: 2004
WestPro is an add-in program designed to work with Microsoft Excel to simulate the growth of uneven-aged Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in the Pacific Northwest region of the United States. Given the initial stand state, defined as the number of softwood and…
Author(s): Rebecca Ralston, Joseph Buongiorno, Benedict Schulte, Jeremy Fried
Keywords: Douglas-fir, Pseudotsuga menziesii, uneven-aged, management, economics, ecology, WestPro, simulation, software, growth model, diversity
Source: Gen. Tech. Rep. PNW-GTR-574. Portland, OR : U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 25 p
Year: 2003
Production of merchantable wood in even-aged Douglas-fir stands can be increased substantially by precommercial thinning. Guidelines for, and gains from, precommercial thinning both strongly depend on the size of trees wanted at the first commercial cut; the larger this size, (1) the fewer trees…
Author(s): Donald L. Reukema
Keywords: Douglas-fir, precommercial thinning, stand improvement, stocking control, stocking density
Source: Gen. Tech. Rep. PNW-GTR-030. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 10 p
Year: 1975
Trends of mean annual increment and periodic annual increment were examined in 17 long-term thinning studies in coast Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) in western Washington, western Oregon, and British Columbia. Maximum ages included ranged from about 90…
Author(s): Robert O. Curtis
Keywords: Growth and yield, mean annual increment, rotation, Douglas-fir, Pseudotsuga menziesii, alternative silviculture, ecosystem management
Source: Res. Pap. PNW-RP-485. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 49 p
Year: 1995
Silvicultural knowledge and practice have been evolving in the Pacific Northwest for nearly a century. Most research and management activities to date have focused on two major topics: (1) methods to regenerate older, naturally established forests after fire or timber harvest; and (2) growth and…
Author(s): R.O. Curtis, D.S. DeBell, C.A. Harrington, D.P. Lavender, J.B. St. Clair, J.C. Tappeiner, J.D. Walstad
Keywords: Ecosystem management, multiple use, silvicultural systems, wildlife habitat, thinning, landscape management, forest ecology, Douglas-fir
Source: Gen. Tech. Rep. PNW-GTR-435. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 123 p
Year: 1998
Large, fallen trees in various stages of decay contribute much-needed diversity to terrestrial and aquatic habitats in western forests. When most biological activity in soil is limited by low moisture availability in summer, the fallen tree-soil interface offers a relatively cool, moist habitat for…
Author(s): Chris Maser, James M. Trappe
Keywords: Fallen trees, decay (wood), decomposition, old-growth stands, Douglas-fir, Pseudotsuga menziesii, mycorrhizae, soil moisture
Source: Gen. Tech. Rep. PNW-GTR-164. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 56 p
Year: 1984
https://www.fs.usda.gov/treesearch/search/query?f%5B0%5D=publication_keywords%3ADouglas-fir