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- A hierarchical classification system separating stream habitat into habitat units defined by stream morphology and hydrology was used in a pre-enhancement stream survey. The system separates habitat units into macrounits, mesounits, and micro- units and includes a separate evaluation of instream cover that also uses the hierarchical scheme. This paper presents an application of the system to a pre-enhancement survey of habitat and salmonid populations. Application of this method accompanied by snorkel counts of fish allowed us to determine habitat area, salmonid densities within habitat...AuthorsM.D. Bryant, B.E. Wright, B.J. DaviesKeywordsSourceRes. Note. PNW-RN-508. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 20 pYear1992
- Morphology and distribution of salmonid habitats were related to the geomorphology of a river basin at three spatial scales including reach (l02-103 m2), subbasin (2-26 km2), and the watershed (240 km2). Stream reaches on a young fluvial terrace (1700 yr old) adjacent to the main river contain the most extensive areas of rearing and spawning habitats. In tributary subbasins, the area of spawning habitat varies according to discharge rates and channel gradients. The most extensive salmonid habitats are located along wide glacial deposits in geologically unconstrained areas of the main...AuthorsL Benda, T.J. Beechie, R.C. Wissmar, A. JohnsonSourceCanadian Journal of Fish and Aquatic Science. 49: 1246-1256Year1992
- A study was undertaken to develop methods for extensive inventory and analysis of wildlife habitats. The objective was to provide information about amounts and conditions of wildlife habitats from extensive, sample based inventories so that wildlife can be better considered in forest planning and policy decisions at the regional scale. The new analytical approach involves identifying habitats present on field plots, estimating area present in each habitat condition, and linking the habitat classifications with wildlife-habitat relationship models to describe habitat suitability for...AuthorsJanet OhmannKeywordsSourceRes. Pap. PNW-RP-440. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 48 pYear1992
- Potential Problems With Q-Values Many ponderosa pine stands have a limited number of size classes, and it may be desirable to carry very large trees through several cutting cycles. Large numbers of trees below commercial size are not needed to provide adequate numbers of future replacement trees. Under these conditions, application of stand density index (SDI) can have advantages over the use of Q-values in defining stocking levels. Calculation of SDI for uneven-aged stands must be done by summing values for individual trees or diameter classes. An example using SDI to derive stocking...AuthorsP.H. CochranSourceRes. Note PNW-RN-509. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 12 pYear1992
- The aggregate timberland assessment system is a time-based deterministic timber projection model. It was developed by the USDA Forest Service to address broad policy questions related to future timber supplies for the 1989 Renewable Resources Planning Act timber assessment. An open framework design allows for customizing inputs to account for regional and subregional growth and yield characteristics, predictions of change in land use, assumptions of future timber management practices, and projections of future demand for stumpage. As inputs, timberland inventories are aggregated into...AuthorsJ.R. Mills, J.C. KincaidKeywordsSourceGen. Tech. Rep. PNW-GTR-281. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research StationYear1992
- We compared survival, reproduction, and body mass of radio-marked and non radio-marked spotted owls (Strix occidentalis) to determine if backpack radios influenced reproduction or survival. In most study areas and years, there were no differences (P > 0.05) in survival of males and females or in survival of radio-marked versus banded owls. There was no difference (P = 0.31) in mean mass of owls before and after they had worn radio transmitters. Radio-marked owls produced fewer (P < 0.01) young than did owls that were not radio-marked. because of the possible relationship between lower...AuthorsC.C. Foster, E.D. Forsman, E.C. Meslow, G.S. Miller, Janice A. Reid, F.F. Wagner, A.B. Carey, J.B. LintKeywordsSourceJournal of Wildlife Management. 56(1): 91-95Year1992
- The PP PRUNE program allows users to conduct a financial analysis of pruning ponderosa pine (Pinus ponderosa Dougl. ex Laws.). The increase in product value and rate of return from pruning the butt 16.5-foot log can be estimated. Lumber recovery information is based on actual mill experience with pruned and unpruned logs. Users supply lumber prices by grade, the cast of pruning, and tree descriptions from growth and yield information. The program estimates the difference in value for trees and stands with and without pruning and the difference in present net worth from adding pruning to a...AuthorsN.A. Bolon, R.D. Fight, J.M. CahillKeywordsSourceGen. Tech. Rep. PNW-GTR-289. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 18 pYear1992
- Results of the first 20 years of the Stampede Creek levels-of-growing-stock study in southwest Oregon are summarized. To age 53, growth in this site III Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand has been strongly related to level of growing stock. Marked differences in volume distribution by tree sizes are developing as a result of thinning. Periodic annual increment is about twice the mean annual increment in all treatments, which indicates that the stand is still far from culmination.AuthorsRobert O. CurtisSourceRes. Pap. PNW-RP-442. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 47 pYear1992
- Results of the Hoskins LOGS study in western Oregon are summarized and management implications discussed through the fifth and final planned treatment period. To age 40 thinnings in this low site I Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stand resulted in large increases in diameter growth with reductions in basal area and volume growth and yield. Growth was strongly related to the level of growing stock. Culmination of cubic-foot mean annual increment does not appear to be near for any of the treatments.AuthorsDavid D. Marshall, John F. Bell, John C. TappeinerKeywordsSourceRes. Pap. PNW-RP-448. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 68 pYear1992
- This book examines the potential of Silvicultural approaches for managing animal damage in forests at two levels: management of free-to-grow stands and sitespecific practices that foster prompt and successful regeneration. Introductory chapters provide a historical perspective of animal damage management in the Pacific Northwest, describe the elements of an integrated approach to forest protection, review the principles of vegetation management and wildlife management, and examine the influence of Silvicultural practices on habitat and animal damage. Individual chapters are devoted to the...AuthorsHugh C. BlackKeywordsSourceGen. Tech. Rep. PNW-GTR-287. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 439 pYear1992