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- Fertilizer placed in the planting hole increased height growth of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) early in the life of the plantation. Later broadcast applications of fertilizer may have had little effect on growth. Wider spacings produced larger trees but less volume per acre than narrower spacings after average tree height exceeded 7 feet. Fertilization produced larger trees and more volume per acre at each spacing.AuthorsP.H. Cochran, R.P. Newman, James W. BarrettSourceRes. Note PNW-RN-500. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 16 pYear1991
- The Timber Resource Inventory Model (TRIM) was used to make several projections of forest industry timber supply for the Douglas-fir region. The sensitivity of these projections to assumptions about management and yields is discussed. A base run is compared to runs in which yields were altered, stocking adjustment was eliminated, harvest assumptions were changed, and management intensity assumptions were changed. The objective was to determine if there is a difference in supply projections and age-class distributions in the short term (20 years) and the long term (50 years) when assumptions...AuthorsSusan J. AlexanderSourceRes. Note. PNW-RN-502. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 20 pYear1991
- Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.AuthorsDebra WarrenKeywordsSourceRes. Bull. PNW-RB-189. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 124 pYear1991
- Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items.AuthorsDebra WarrenKeywordsSourceRes. Bull. PNW-RB-187. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 116 pYear1991
- Before a bird population is measured, the objectives of the study should be clearly defined. Important factors to be considered in designing a study are study site selection, plot size or transect length, distance between sampling points, duration of counts, and frequency and timing of sampling. Qualified field personnel are especially important. Assumptions applying to all bird-counting techniques are discussed. The following techniques and their applications are discussed; simple line transect, fixed-width transect, variable-width transect, simple point count, fixed-radius point count,...AuthorsD.A. Manuwal, A.B. CareyKeywordsSourceGen. Tech. Rep. PNW-GTR-278. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research StationYear1991
- Three arboreal rodents are sensitive indicators of forest ecosystem function in the Pacific Northwest. The northern flying squirrel (Glaucomys sabrinus) is mycophagous, cavity-nesting, and a major prey of the spotted owl (Strix occidentalis). The red tree vole (Phenacomys longicaudus) is restricted to trees and may prove sensitive to forest fragmentation. The Douglas' squirrel (Tamiasciurus douglasi) responds sharply to fluctuations in conifer seed abundance. Live-trapping and mark and recapture methods can be used to estimate densities of northern flying squirrels and some other rodents...AuthorsAndrew B. Carey, Brian Biswell, Joseph W. WittKeywordsSourceGen. Tech. Rep. PNW-GTR-273. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 24 pYear1991
- Seed weight, time of emergence, and three measures of seedling size were recorded for 39 open-pollinated Douglas-fir (Pseudotsuga menziesii var. menziesii[Mirb.] Franco) families in order to assess family variation in seed weight and emergence, and the influence of these seed traits on early growth. Families were planted both as ungerminated seed and as recent germinants to test whether using germinants minimized seed effects on early growth. To evaluate the effect of competition on the relationships of seed weight and rate of emergence to seedling size, individuals of families were...AuthorsJ.B. St. Clair, W.T. AdamsKeywordsSourceForest Science. 37(4): 987-997Year1991
- Statistics on forest area, total gross and net timber volumes, and annual net growth and mortality are presented from the 1983-84 timber inventory of the Stikine Area, Tongass National Forest, Alaska. Available timberland area is estimated at 1.2 million acres, net growing stock volume at 7.2 billion cubic feet, and annual net growth and mortality at 18.8 and 57.0 million cubic feet, respectively.AuthorsGeorge Rogers, Wlllem W.S. van HeesSourceRes. Bull. PNW-RB-185. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 19 pYear1991
- Three experiments were conducted to determine effects of N and P fertilizers on growth and levels of plant-tissue nutrients of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sarg.). Both pole-size trees in closed-canopy stands and potted seedlings were use d . Soil series were Bunker for Douglas-fir and Klone for western hemlock in experiments 1 and 3, and Vesta in experiment 2. For each species in experiments 1 and 2, P and N fertilizers were tested in six or eight treatments using factorial design. In experiment 3, N and P fertilizers...AuthorsM.A. Radwan, J.S. Shumway, D.S. Debell, J.M. KraftSourceCanadian Journal of Forest Research. 21: 1431-1438.Year1991
- Construction specifications and illustrations are provided for several types of barbed wire and pole fences, gates, cattle guards, stiles, spring developments, water troughs, stock ponds, trick tanks, and livestock access trails.AuthorsH. Reed Sanderson, Thomas M. Quigley, Emery E. Swan, Louis R. SpinkKeywordsSourceGen. Tech. Rep. PNW-GTR-250. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 126 pYear1990