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- This paper describes the operation of the microcomputer program HEIWEST, which was developed to automate calculation of the western Oregon elk habitat effectiveness index (HEI). HEIWEST requires little or no training to operate and vastly simplifies the task of measuring HEI for either site-specific project analysis or long-term monitoring of elk habitat. It is especially useful as a project analysis tool where many silvicultural alternatives are evaluated for their effects on elk habitat. The program also can be used to calculate interior habitat and edge length for indices for forest...AuthorsAlan Ager, Mark HitchcockSourceGen. Tech. Rep. PNW-GTR-303. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 12 pYear1992
- The Alaska vegetation classification presented here is a comprehensive, statewide system that has been under development since 1976. The classification is based, as much as possible, on the characteristics of the vegetation itself and is designed to categorize existing vegetation, not potential vegetation. A hierarchical system with five levels of resolution is used for classifying Alaska vegetation. The system, an agglomerative one, starts with 888 known Alaska plant communities, which are listed and referenced. At the broadest level of resolution, the system contains three formations-fore...AuthorsL.A. Viereck, C.T. Dyrness, A.R. Batten, K.J. WenzlickKeywordsSourceGen. Tech. Rep. PNW-GTR-286. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 278 pYear1992
- The rooting percentages of 14 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) clones were examined annually from 1974 to 1988. The trees were 10 and 13 years old in 1974 and were pruned to 2.0 m in 1978 and 1979 and then recut annually to 0.5, 1.0, or 1.5 m, starting in 1983. The pruned trees showed no evidence of decreased rooting percentage even after 15 years; average rooting increased from 0.5 m tall ramets exhibited better rooting than cuttings from 1.0 or 2.0 m tall ramets, and cuttings from 1.0 m tall ramets rooted better than cuttings from 2.0 m tall ramets. Rooting of cuttings...AuthorsD.L. CopesSourceCanadian Journal of Forest Research. 22: 1888-1894Year1992
- The 1730-ha Serpentine Slide Research Natural Area (RNA) is located in central Alaska in the White Mountains National Recreation Area. It is managed by the U.S. Department of the Interior, Bureau of Land Management, Steese-White Mountains District. Serpentine Slide was selected as a Research Natural Area (RNA) because it contains an alpine exposure of serpentinite; a 9-ha natural earth flow that has destroyed most vegetation in its path; bottom-land white spruce and balsam poplar forests growing on coarse gravels and sands of a major clearwater river flood plain; and warm, dry hill...AuthorsG.P. JudayKeywordsAlaska, beaver, Castor canadensis, earthslide, ecosystems, goshawk, Accipiter gentilis, grizzly bear, Ursus arctos, hill prairie, Research Natural Area, Natural Areas (Research), northern wood frog, Rana sylvatica, old-growth forest, scientific reserves, serpentine, semipalmated plover, Charadrius semipalmatus, white spruce, Picea glaucaSourceGen. Tech. Rep. PNW-GTR-271. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 66 pYear1992
- A series of experiments was conducted over 4 years to test and develop methods to produce acceptable red alder planting stock and to assess quality and outplanting performance of resulting stock. Results indicated that red alder planting stock can be produced as containerized seedlings (plugs) or as bare-root nontransplant and transplant trees. In general, bare-root stock is larger and, hence, preferred over containerized trees, especially for planting on harsh sites or on any site where time considerations are important.AuthorsM.A. Radwan, Y. Tanaka, A. Dobkowskl, W. FangenSourceRes. Pap. PNW-RP-450. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 13 pYear1992
- The seasonal and spatial patterns of dispersal of white spruce (Picea glauca (Moench) Voss) seed were studied from 1986 to 1989 in floodplain stands along the Tanana River near Fairbanks, Alaska. Analysis of the 1987 crop showed that production of filled seed was strongly related to estimated production of total seed and unrelated to selected stand structural characteristics. A mathematical expression, developed to estimate dispersal of filled seed into clearcut openings, predicted dispersal between 10 and 120 meters from the edge of an opening. The pattern of wind during the seed-dispersal...AuthorsAndrew Youngblood, Timothy A. MaxKeywordsSourceRes. Pap. PNW-RP-443. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 17 pYear1992
- Cones were collected from 272 trees at 189 locations uniformly distributed over the east slopes of the Oregon Cascade Range and Warner Mountains. Variation in seed and seedling traits was related to (1) seed source latitude, distance from the Cascade crest, elevation, slope, and aspect in multiple regression analyses; and (2) seed zone and elevation band in classification analyses. Provisional seed transfer guidelines are presented. These include a regression equation for guiding seed transfer and estimating transfer risk, and a new outline of fixed seed zones.AuthorsFrank SorensenKeywordsSourceRes. Pap. PNW-RP-453. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 30 pYear1992
- A proceedings of a conference held to stimulate interaction among people working in areas of forest protection and silviculture and on issues of national and international concern relative to forest insect and disease management, education, and research. National issues addressed were forest productivity, stewardship, biological diversity, and new perspectives and how these issues affect environmentally sound management of forest pests.AuthorsD.C. Allen, L.P. AbrahamsonKeywordsSourceGen. Tech. Rep. PNW-GTR-294. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 182 pYear1992
- Forest Service air resource managers in the Pacific Northwest are responsible for protecting class 1 wilderness areas from air pollution. To do this, they need scientifically defensible information to determine critical concentrations of air pollution having the potential to impact class 1 wilderness values. This report documents the results of a workshop where current information on air pollution effects on aquatic and terrestrial resources and visibility was gathered from participating scientists and managers. Critical air pollution concentrations were determined for sulfur dioxide,...AuthorsJ. Peterson, D. Schmoldt, D. Peterson, J. Eilers, R. Fisher, R. BachmanKeywordsSourceGen. Tech. Rep. PNW-GTR-299. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 83 pYear1992
- A recent lumber recovery study of pruned and unpruned ponderosa pine (Pinus ponderosa Dougl. ex Laws.) was used to project the financial return from pruning ponderosa pine in the Medford District of the Bureau of Land Management and in the Ochoco and Deschutes National Forests. The cost of pruning at which the investment would yield an expected 4-percent real rate of return was positive on sites where individual tree growth is fairly high, pruning is done as early as biologically possible given crown removal limitations, and the harvest is 30 to 70 years after pruning. The better situations...AuthorsRoger D. Fight, Natalie A. Bolon, James M. CahillKeywordsSourceRes. Pap. PNW-RP-449. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 17 p.Year1992