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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
In order to address policy issues relating to biodiversity, productivity, and sustainability, we need detailed understanding of forest vegetation at broad geographic and time scales. Most existing maps developed from satellite imagery describe only general characteristics of the upper canopy.…
Author(s): Sally Duncan
Source: Science Findings 56. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 1-5
Year: 2003
New height growth and site index curves for red alder (Alnus rubra Bong.) were developed from stem analysis data. The analyses use a reference (site index) age of 20 years and are applicable to natural stands between 5 and 50 years of age in western Washington and northwestern Oregon. The new…
Author(s): Constance A. Harrington, Robert O. Curtis
Keywords: increment (height), site index, site class, red alder, Alnus rubra
Source: Res. Pap. PNW-RP-358. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 14 p
Year: 1985
This report supplements a slide-tape presentation of the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir forests in western Washington and Oregon and the effects of this fertilization on tree growth and water quality. Part II discusses…
Author(s): Richard E. Miller, Roger D. Right
Source: Gen. Tech. Rep. PNW-GTR-083. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 29 p
Year: 1979
Continuing conversion of woodlands, greater restrictions on recreational access, and subdivision are trends seeming to have important implicaitons for future public recreation supply. The nature of these implicaitons has not been adequately explored in previous research, a void that has led to…
Author(s): H. Ken Cordell, Donald B.K. English, Sharon A. Randall
Keywords: private lands, leasing, subdivision, recreation supply, recreational access, access models
Source: Gen. Tech. Rep. RM-GTR-231. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 21 p.
Year: 1993
Summary In most tree species, inbreeding greatly reduces seed production, seed viability, survival and growth. In a previous large-scale quantitative analysis of a black spruce (Picea mariana (Mill.) B.S.P.) diallel experiment, selfing had large deleterious effects on growth but no impact on stable…
Author(s): Kurt Johnsen, John E. Major, Chris A. Maier
Keywords: carbon isotope discrimination, photosynthesis, Picea mariana, stomatal conductance
Source: Tree Physiology 23, 1005–1008
Year: 2003
Traditional methods of measuring tree root biomass are labor intensive and destructive in nature. We studied the utility of ground-penetrating radar (GPR) to measure tree root biomass in situ within a replicated, intensive culture forestry experiment planted with loblolly pine (Pinus taeda L.). The…
Author(s): John R. Butnor, J.A. Doolittle, Kurt H. Johnsen, L. Samuelson, T. Stokes, L. Kress
Source: Soil Science Society of America Journal 67:1607–1615
Year: 2003
The Recreation Opportunity Spectrum (ROS) is one of the most powerful recreation inventory tools ever devised. Originally formulated in the late 1970?s for use on public lands in the Western United States, the ROS was quickly adopted by federal land-management agencies. However, its application to…
Author(s): Thomas A. More, Susan Bulmer, Linda Henzel, Ann E. Mates
Keywords: Recreation Opportunity Spectrum, recreation experience, planning
Source: Gen. Tech. Rep. NE-309. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern Research Station. 25 p.
Year: 2003
Estimated changes in carbon stocks are reported for the forests and wood products of the 50 U.S. States. Carbon stocks on forest land and in harvested wood products increased between 1987 and 1997 at an annual rate of 190 million metric tons. Most of this increase was in biomass, followed closely…
Author(s): R.A. Birdsey, G.M. Lewis
Keywords: global change, forest carbon, forest inventory
Source: Gen. Tech. Rep. NE-310. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northeastern Research Station. 42 p.
Year: 2003
This paper reviews procedures for establishing and maintaining permanent plots for silvicultural and yield research; discusses purposes, sampling, and plot design; points out common errors; and makes recommendations for research plot designs and procedures for measuring and recording data.
Author(s): Robert O. Curtis
Keywords: Plot analysis, permanent sample plots, tree measurement, sample plot design
Source: Gen. Tech. Rep. PNW-GTR-155. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 56 p
Year: 1983
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