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- Tree improvement programs have generally relied on testing families in open light environments. With increased interest in multiaged silvicultural systems, some people have questioned whether families selected in the open are appropriate for planting in the shade. We grew Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) families from two climatically distinct seed sources for 2 years under four levels of shade. The response to shade differed for several traits between the two populations and among families within populations. The magnitude of variation associated with the...AuthorsJ. Bradley St. Clair, Richard A. SniezkoSourceCanadian Journal of Forest Research. 29: 1751-1763.Year1999
- Landscapes administered for timber production by the U.S. Forest Service in the Pacific Northwest in the 1950s-1980s were managed with dispersed patch clearcutting, and then briefly in the late 1980s with aggregated patch clearcutting. In the late 1990s, use of historical landscape patterns and disturbance regimes as a guide for landscape management has emerged as an alternative to the static reserves and standard matrix prescriptions in the Northwest Forest Plan. Use of historical information to guide management recognizes the dynamic and variable character of the landscape and may offer...AuthorsJ.H. Cissel, F.J. Swanson, P.J. WeisbergSourceEcological Applications. 9(4): 1217-1231Year1999
- Conservation of biodiversity provides for economic, social, and environmental sustainability. Intentional management is designed to manage conflicts among groups with conflicting interests. Our goal was to ascertain if intentional management and principles of conservation of biodiversity could be combined into upland and riparian forest management strategies that would be applicable to various land ownerships and, consequently, help resolve land allocation problems associated with timber supply and threatened wildlife. We used computer simulations to model three divergent management...AuthorsA.B. Carey, B.R. Lippke, J. SessionsSourceJournal of Sustainable Forestry. 9(3/4): 83-125Year1999
- Although the phrase, "planting for ecosystem restoration," is of recent origin, many of the earliest large-scale tree plantings were made for what we now refer to as "'restoration" or "conservation" goals. Forest restoration activities may be needed when ecosystems are disturbed by either natural or anthropogenic forces. Disturbances can impact (1) basic components of the system (e.g., plant and animal composition, soil pools, and atmospheric pools), (2) ecosystem processes, i.e., interactions among basic components, or (3) both components and processes. Early efforts at restoration or...AuthorsConstance A. HarringtonSourceNew Forests. 17: 175-190Year1999
- Management activities of the 20th century, especially fire exclusion, timber harvest, and domestic livestock grazing, have significantly modified vegetation spatial patterns of forests and ranges in the interior Columbia basin. Compositional patterns as well as patterns of living and dead structure have changed. Dramatic change in vital ecosystem processes such as fire, insect, and pathogen disturbances, succession, and plant and animal migration is linked to recent change in vegetation patterns. Recent change in vegetation patterns is also a primary reason for current low viability and...AuthorsPaul F. Hessburg, Bradley G. Smith, Scott D. Kreiter, Craig A. Miller, R. Brion Salter, Cecilia H. McNicoll, Wendel J. HannKeywordsLandscape characterization, ecological assessment, vegetation patterns, interior Columbia River basin, Klamath Basin, Great Basin, ecosystem health, vegetation pattern-disturbance process interactions, insect and disease disturbance, landscape ecology, ecosystem processes, potential natural vegetation modeling, vegetation change, fire effectsSourceGen. Tech. Rep. PNW-GTR-458. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 357 p. (Quigley, Thomas, M., ed., Interior Columbia Basin Ecosystem Management Project: scientific assessment)Year1999
- The effect of a fuels reduction treatment on small mammals was investigated in lodgepole pine (Pinus contorta) and mixed conifer stands by trapping and track surveys in northeastern Oregon. The number of red squirrel (Tamiasciurus hudsonicus) and snowshoe hare (Lepus americanus) tracks decreased in all lodgepole pine treatments after harvest. Only two snowshoe hare tracks were detected in harvested stands of mixed conifer, compared with 46 tracks in unharvested stands. In most treatments the number of red-backed voles (Clethrionomys gapperi) decreased and chipmunks (Tamius spp.) increased...AuthorsEvelyn Bull, Arlene K. BlumtonKeywordsSourceRes. Note PNW-RN-539. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 9 pYear1999
- We provide efficient and accurate methods for sampling snags and large trees on a landscape to conduct compliance and effectiveness monitoring for wildlife in relation to the habitat standards and guidelines on National Forests. Included online are the necessary spreadsheets, macros, and instructions to conduct all surveys and analyses pertaining to estimation of snag and large tree densities and distributions at the subwatershed scale. The methods focus on optimizing sampling effort by choosing a plot size appropriate for the specific forest conditions encountered. Two methods are...AuthorsLisa J. Bate, Edward O. Garton, Michael WisdomKeywordsSourceGen. Tech. Rep. PNW-GTR-425. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 76 pYear1999
- Bushy-tailed woodrats (Neotoma cinerea) and dusky-footed woodrats (N. fuscipes) add substantially to the prey base of many avian and mammalian predators. High biomass of woodrats can reduce markedly area requirements of predators; thus, management for woodrats has potential in conservation. But patterns of abundance of woodrats in the Pacific Northwest are poorly understood. Our objective was to determine local abundances and regional distributions of N. cinerea and N. fuscipes in forests west of the Crest of the Cascade Range in Oregon and Washington. We sampled a variety of forests from...AuthorsAndrew B. Carey, Christine C. Maguire, Brian Biswell, Todd M. WilsonSourceNorthwest Science. 73(2): 65-80Year1999
- Although ecosystem management techniques are designed to enhance species diversity in managed forests, no comprehensive study has been conducted to evaluate effects of such techniques on diversity and productivity of hypogeous fungi (truffles). During this study, truffles were collected in a 55- to 65-year-old Douglas-fir forest from March 1993 through December 1995 at approximately 6-week intervals. Half of the stands served as controls, half were assigned a variable density thinning (VDT) treatment. A VDT stand comprised a mosaic of patches thinned to different densities of standing live...AuthorsW.C. III Colgan, A.B. Carey, J.M. Trappe, R. Molina, D. ThysellSourceCanadian Journal of Forestry Resources. 29: 1259-1268Year1999
- Silvicultural practices can influence black bear (Ursus americanus) foraging preferences for Douglas-fir (Pseudotsuga menziesii) cambial-zone vascular tissues, but little is known about the role of genetics. To study the impact of genetic selection, vascular tissue samples were collected from Douglas-fir trees in six half-sib families from five different sites in north central Oregon. Four replications of three-tree non-contiguous plots were sampled at each site to examine inter- and intra-site variation. Tree growth was measured as tree diameter at breast height and the absolute concentrat...AuthorsBruce A. Kimball, G.R. Johnson, Dale L. Nolte, Doreen L. GriffinKeywordsSourceForest Ecology and Management. 123: 245-251Year1999