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- This document provides land managers with practical suggestions for implementing ecosystem management. It contains 28 papers organized into five sections: historical perspectives, ecological principles, sampling design, case studies, and implementation strategies.AuthorsM.E. Jensen, P.S. BourgeronSourceGen. Tech. Rep. PNW-GTR-318. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 376 p. (Everett, Richard L., assessment team leader; Eastside forest ecosystem health assessment)Year1994
- The traditional approach to wildlife management has focused on single species—historically game species and more recently threatened and endangered species. Several newer approaches to managing for multiple species and biological diversity include managing coarse filters, ecological indicator species, indicator guilds, and use of species-habitat matrices. These and other modeling approaches each have strong points as well as weak points, which include conflicts among objectives for species with disparate needs. We present three case examples of integrating management for single species...AuthorsBruce G. Marcot, Michael Wisdom, Hiram W. Li, Gonzalo C. CastilloKeywordsSourceGen. Tech. Rep. PNW-GTR-329. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 39 p. (Everett, Richard L., assessment team leader; Eastside forest ecosystem health assessment; Hessburg, Paul F., science team leader and tech. ed., Volume III: assessment.)Year1994
- Projections of Alaska timber products output, the derived demand for raw material, and timber harvest by owner are developed from a trend-based analysis. By using a spread-sheet model, material flows in the Alaska forest sectorare fully accounted for. Demand for Alaska national forest timber is projected and depends on product output and harvest by other owners. Key assumptions are made explicit, and the sensitivity of the model output to changes in assumptions is examined.AuthorsD.J. Brooks, R.W. HaynesSourceGen. Tech. Rep. PNW-GTR-334. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 32 pYear1994
- Of the 15 species of bats in the Pacific Northwest, 11 are known to make regular use of the forest canopy for roosting, foraging, and reproduction. This paper reviews roosting requirements, foraging, and the importance of landscape-scale factors to canopy using species in the Northwest. Many northwest bats use several different types of tree roosts. Common roosting sites are in cavities, crevices, and foliage. Factors that may be important in roost site selection include microclimate, roost structure, crown architecture, canopy tree age and species, bark characteristics, foliage density,...AuthorsL. Wunder, A.B. CareySourceNorthwest Science. 68(2): 159Year1994
- The May 18, 1980, eruption of Mount St. Helens in Washington is possibly the best documented geological event in history. The bibliography displays the results of 13 years of biological and related research in a convenient, indexed format. Our intent is to facilitate collaboration between scientists contemplating new research initiatives and experienced investigators who have conducted baseline studies at the volcano. Prospective investigators are encouraged to contact the Monument Scientist and individual authors listed in the research abstracts to find out more about research opportunitie...AuthorsPeter M. Frenzen, Anne M. DelanoKeywordsSourceGen. Tech. Rep. PNW-GTR-342. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 160 pYear1994
- BIOPAK is a menu-driven package of computer programs for IBM-compatible personal computers that calculates the biomass, area, height, length, or volume of plant components (leaves, branches, stem, crown, and roots). The routines were written in FoxPro, Fortran, and C. BIOPAK was created to facilitate linking of a diverse array of vegetation datasets with the appropriate subset of available equations for estimating plant components, such as biomass and leaf area. BIOPAK produces reports that are formatted for people and files that are compatible with other software. Other reports document...AuthorsJoseph E. Means, Heather A. Hansen, Greg J. Koerper, Paul B Alaback, Mark W. KlopschKeywordsSourceGen. Tech. Rep. PNW-GTR-340. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 184 pYear1994
Snag abundance for primary cavity-nesting birds on nonfederal forest lands in Oregon and Washington.
More than 100 species of vertebrates in the Pacific Northwest use standing dead trees (snags) at one time or another in their lifecycle (Thomas et al. 1979a, Neitro et al. 1985). With few exceptions, investigators have found significant correlations between snag density and the abundance of primary cavity-nesters in North American coniferous forests (Raphael and White 1984:47-53, Madsen 1985, Zarnowitz and Manuwal 1985, McComb et al. 1986, Land et al. 1989, Carey et al. 1991, Schreiber and deCalesta 1992). Similar relationships have been detected for secondary cavity-nesters (Schreiber and...AuthorsJanet Ohmann, William C. McComb, Abdel Azim ZumrawiSourceWildlife Society Bulletin. 22: 607-620Year1994- Results of the Iron Creek installation of the levels-of-growing-stock study in Douglasfir (Pseudotsuga menziesii (Mirb.) Franco) are summarized. To age 42 (planned completion of the experiment) volume growth in this site II Douglas-fir plantation has been strongly related to level of growing stock, partially offsetting the decrease in volume growth percent expected with increasing growing stock. Basal area growth-growing stock relations were much weaker than those for volume. Marked differences in tree size distributions have resulted from thinning. Periodic annual volume increments are...AuthorsRobert O. Curtis, Gary W. ClendenenKeywordsSourceRes. Pap. PNW-RP-475. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 77 pYear1994
- This paper examines by climax conifer series, historical and current roles of many important pathogens and insects of interior Northwest coniferous forests, and their unique responses to changing successional conditions resulting from management. Insects and pathogens of the subalpine fir and mountain hemlock series historically reduced inter-tree competition for site resources, and generated most of the coarse woody debris between fires. Severity of growth and mortality effects was proportional to the abundance of susceptible seral species such as Douglas-fir, grand fir, and lodgepole...AuthorsP.F. Hessburg, R.G. Mitchell, G.M. FilipKeywordsSourceGen. Tech. Rep. PNW-GTR-327. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 72 p. (Everett, Richard L., assessment team leader; Eastside forest ecosystem health assessment; Hessburg, Paul F., science team leader and tech. ed., Volume III: assessment.)Year1994
- We analyzed historical and current vegetation composition and structure in 49 sample watersheds, primarily on National Forests, within six river basins in eastern Oregon and Washington. Vegetation patterns were mapped from aerial photographs taken from 1932 to 1959, and from 1985 to 1992. We described vegetation attributes, landscape patterns, the range of historical variability, scales of change, and disturbance hazards. Forest cover increased eight percent in three river basins, but remained relatively unchanged in the other basins. Forests became more dense in vertical and horizontal...AuthorsJ.F. Lehmkuhl, P.F. Hessburg, R.L. Everett, M.H. Huff, Roger D. OttmarKeywordsSourceGen. Tech. Rep. PNW-GTR-328. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 88 p. (Everett, Richard L.; team leader; Eastside forest ecosystem health assessment; Hessburg, Paul F., science team leader and tech. ed., Volume III: assessment.)Year1994