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- Developing and displaying forest structural targets are crucial for sustaining the habitats of the northern goshawk, a sensitive species in Southwestern forests. These structural targets were described in Management Recommendations for the Northern Goshawk in the Southwestern United States (MRNG) (Reynolds, et al., 1992). The MRNG were developed in a unique food-web approach that identified desired forest conditions for the goshawk. These desired conditions were based on syntheses of the habitats of both goshawks and the diverse suite of plants and animals in their food web. Not surprisingl...AuthorsJames A. Youtz, Russell T. Graham, Richard T. Reynolds, Jerry SimonKeywordsSourceIn: Integrated restoration of forested ecosystems to achieve multiresource benefits: Proceedings of the 2007 national silviculture workshop. Gen. Tech. Rep. PNW-GTR-733. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. p. 173-191Year2008
- Soils are fundamental to a healthy and functioning ecosystem. Therefore, forest land managers can greatly benefit from a more thorough understanding of the ecological impacts of fire and fuel management activities on the vital services soils provide. We present a summary of new research on fire effects and soils made possible through the Joint Fire Science Program and highlight management implications where applicable. Some responses were consistent across sites, whereas others were unique and may not easily be extrapolated to other sites. Selected findings include (1) postfire soil water...AuthorsHeather Erickson, Rachel WhiteKeywordsSourceGen. Tech. Rep. PNW-GTR-759. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 17 p.Year2008
- This paper synthesizes the existing literature about traditional and local ecological knowledge relating to biodiversity in Pacific Northwest forests in order to assess what is needed to apply this knowledge to forest biodiversity conservation efforts. We address four topics: (1) views and values people have relating to biodiversity, (2) the resource use and management practices of local forest users and their effects on biodiversity, (3) methods and models for integrating traditional and local ecological knowledge into biodiversity conservation on public and private lands, and (4)...AuthorsSusan Charnley, A. Paige Fischer, Eric T. JonesKeywordsSourceGen. Tech. Rep. PNW-GTR-751. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 52 p.Year2008
- Development of a new turfgrass cultivar requires an evaluation of numerous traits as well as an understanding of environmental factors influencing those traits. Growth or ability to fill in gaps and time of fall dormancy (fall color retention) that indicates cold hardiness are important traits for turfgrasses. This study was initiated to characterize variation in saltgrass [Distichlis spicata L. (Greene)] growth and time of fall dormancy related to climatic and geographical factors at the source location (geographical location of clone origin). Growth traits and time of fall dormancy were...AuthorsHrvoje Rukavina, Harrison HughesSourceJournal of American Society of Horticultural Science. 133(1): 127-132Year2008
- Over a 3-day weekend in the spring of 2004 a group of scientists interested in extending understanding of place as applied in recreation research and management convened a working session in Portland, Oregon. The purpose of the gathering was to clarify their understanding of place-related concepts, approaches to the study of people-place relations, and the application of that understanding in recreation management for the purpose of integrating perspectives from different disciplines, discussing approaches to understanding and measuring sense of place, and other questions around the study...AuthorsLinda. E. Kruger, Troy E. Hall, Maria StiefelKeywordsSourceGen. Tech. Rep. PNW-GTR-744. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 204 p.Year2008
- Eighteen precommercial thinning trials were established in true fir-hemlock stands in the Olympic Mountains and the west side of the Cascade Range during the period 1987 through 1994. This paper updates a previous report, with results for the first 10 years after establishment. Results are given for (1) all trees, (2) the largest 80 per acre of any species, and (3) those noble fir (Abies procera Rehd.) and Pacific silver fir (Abies amabilis Dougl. ex Forbes) included in the largest 80 per acre. Diameter growth of all species increased with increase in spacing. Height growth of Pacific...AuthorsRobert O. CurtisKeywordsSourceGen. Tech. Rep. PNW-GTR-749. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 36 pYear2008
- We describe a protocol to monitor the effectiveness of the Tongass Land Management Plan (TLMP) management standards for maintaining fish habitat. The protocol uses juvenile coho salmon (Oncorhynchus kisutch) in small tributary streams in forested watersheds. We used a 3-year pilot study to develop detailed methods to estimate juvenile salmonid populations, measure habitat, and quantitatively determine trends in juvenile coho salmon abundance over 10 years. Coho salmon have been shown to be sensitive to habitat alterations, and we use coho salmon parr as the primary indicator in the...AuthorsM.D. Bryant, Trent McDonald, R. Aho, B.E. Wright, Michelle Bourassa StahlSourceGen. Tech. Rep. PNW-GTR-743. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 80 p.Year2008
- We developed new equations to predict Oregon white oak (Quercus garryana Dougl. ex Hook.) development with ORGANON, a stand-development model that is widely used in the Pacific Northwest. Tree size, competitive status, crown ratio, and site productivity were statistically significant predictors of growth and mortality. Three scenarios were projected with the new equations, the previous ORGANON model, and the Forest Vegetation Simulator. Compared with the two other models, the new equations predicted greater diameter growth in oak woodland and a greater effect of conifer removal in a...AuthorsPeter Gould, David D. Marshall, Constance A. HarringtonKeywordsSourceWestern Journal of Applied Forestry. 23(1): 26-33Year2008
- We estimated the impact of global climate change on lodgepole pine (Pinus contorta Dougl. ex. Loud. var. latifolia Engelm.) site productivity in Alberta based on the Alberta Climate Model and the A2 SRES climate change scenario projections from three global circulation models (CGCM2, HADCM3, and ECHAM4). Considerable warming is apparent in all three models. On average, the increases in mean GDD5 (growing degree-days >5 °C) are 18, 38, and 65 percent by the 2020s, 2050s, and 2080s, respectively. Change in precipitation is essentially nil. This results in proportional increases in dryness...AuthorsRobert Monserud, Yuqing Yang, Shongming Huang, Nadja TchebakovaKeywordsSourceCanadian Journal of Forest Research. 38: 343-352Year2008
- The physiological mechanisms responsible for reduced extension growth as trees increase in height remain elusive. We evaluated biophysical constraints on leaf expansion in old-growth Douglas-fir (Psuedotsuga menziesii (Mirb.) Franco) trees. Needle elongation rates, plastic and elastic extensibility, bulk leaf water, (ΨL) and osmotic (ΨΠ) potential, bulk tissue yield threshold, and final needle length were characterized along a height gradient in crowns of > 50-m-tall trees during the period between bud break and full expansion (May to June). Although needle length decreased...AuthorsFrederick Meinzer, Barbara J. Bond, Jennifer A. KaranianKeywordsSourceTree Physiology. 28: 197-206Year2008