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- A floral survey in the Olympic National Forest and its surroundings revealed that a considerable number of introduced ruderal plant species have made deep inroads into the stands of native flora. Some of them, which are mainly of European and Asian origin, have been planted deliberately to stabilize the soil along roadsides and after clear cutting and burning. However, they have already established reproductive communities that are capable of spreading rapidly without additional human help as they have already done in almost all regions of the earth subject to a temperate climate. Plotting...AuthorsCharles W. HeckmanSourceNorthwest Science. 73(4): 264-276Year1999
- In the West, thinning and partial cuttings are being considered for treating millions of forested acres that are overstocked and prone to wildfire. The objectives of these treatments include tree growth redistribution, tree species regulation, timber harvest, wildlife habitat improvement, and wildfire-hazard reduction. Depending on the forest type and its structure, thinning has both positive and negative impacts on crown fire potential. Crown bulk density, surface fuel, and crown base height are primary stand characteristics that determine crown fire potential. Thinning from below, free...AuthorsRussell T. Graham, Alan E. Harvey, Terrie B. Jain, Jonalea TonnKeywordsSourceGen. Tech. Rep. PNW-GTR-463. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 27 pYear1999
- We quantified the amount, spatial distribution, and importance of salmon (Oncorhynchus spp.)-derived nitrogen (N) by brown bears (Ursus arctos) on the Kenai Peninsula, Alaska. We tested and confirmed the hypothesis that the stable isotope signature (δ15N) of N in foliage of white spruce (Picea glauca) was inversely proportional to the distance from salmon-spawning streams (r=-0.99 and PAuthorsGrant V. Hilderbrand, Thomas Hanley, Charles T. Robbins, Charles C. SchwartzKeywordsSourceOecologia. 121: 546-550Year1999
- Population dynamics and demography of the Sitka mouse, Peromyscus keeni sitkensis, were studied by mark-recapture live-trapping over a 4-year period in four floodplain and upland forest habitats: old-growth Sitka spruce (Picea sitchensis) floodplain; red alder (Alnus rubra) floodplain; beaver-pond floodplain; and nearby old-growth Sitka spruce-western hemlock (Tsuga heterophylla) upland forest. We did not find the expected source-sink population dynamics resulting from flood disturbance or between-habitat variation in food resources. We found significant between-year differences (P < 0.05)...AuthorsT.A. Hanley, J.C. BarnardKeywordsSourceJournal of Mammalogy. 80(3): 866-879Year1999
- Sang numbers and decay class were measured on a chronosequence of 26 wildfires (ages 1-81 years) on the east slope of the Cascade Range in Washington. Snag longevity and resultant snag densities varied spatially across burns in relation to micro-topographic position. Longevity of snags < 41 cm dbh was greater for thin-barked engelmann spruce (Picea engelmannii), subalpine fir (Abies lasiocarpa) and lodgepole pine (Pinus contorta) than thick-barked Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa). With larger diameter snags, however, Douglas-fir persisted longer than...AuthorsRichard L. Everett, John F. Lehmkuhl, Richard Schellhaas, [and others].SourceInternational Journal of Wildland Fire. 9(4): 223-234Year1999
- Understanding the concepts of place in ecosystem management may allow land managers to more actively inventory and understand the meanings that people attach to the lands and resources under the care of the land manager. Because place assessment has not been used operationally in past large-scale evaluations and analyses, it was necessary in the assessment of the interior Columbia basin (hereafter referred to as the basin) to apply theories based on available literature. These theories were used within two large test areas inside the assessment area boundaries. From the test area experience...AuthorsSteven J. Galliano, Gary M. LoefflerKeywordsSourceGen. Tech. Rep. PNW-GTR-462. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 31p. (Quigley, Thomas M., ed.; Interior Columbia Basin Ecosystem Management Project: scientific assessment)Year1999
- This monograph is an examination of the experience in the Pacific Northwest implementing the Northwest Forest Plan, Economic Adjustment Initiative (NWEAI). First, a brief description of the NWEAI background and framework, and a socioeconomic overview of the region prior to the NWEAI provide the setting. Next, accounts of the NWEAI experience in each of the three states in the region; a chapter on the NWEAI impact on people and communities’ and a review of field level efforts to implement business, local government, and ecosystem management projects build a comprehensive picture of the...AuthorsHarriet H. Christensen, Terry L. Raettig, Paul Sommers, [tech. eds.].KeywordsSourceGen. Tech. Rep. PNW-GTR-484. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 103 p. In cooperation with: Northwest Policy Center, Institute for Public Policy and Management, University of WashingtonYear1999
- The guide describes use of the NetWeaver knowledge base development system. Knowledge representation in NetWeaver is based on object-oriented fuzzy-logic networks that offer several significant advantages over the more traditional rulebased representation. Compared to rule-based knowledge bases, NetWeaver knowledge bases are easier to build, test, and maintain because the underlying object-based representation makes them modular. The modularity of NetWeaver knowledge bases, in turn, allows designers to gradually evolve complex knowledge bases from simpler ones in small, simple steps....AuthorsKeith M. ReynoldsKeywordsSourceGen. Tech. Rep. PNW-GTR-471. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 75 pYear1999
- This strategic plan is a technical discussion of the implementation and development of models and data systems used to manage the air quality impacts of wildland and prescribed fires. Strategies and priorities in the plan were generated by the Express Team (chartered by the National Wildfire Coordinating Group) and a diverse group of 86 subject matter experts who attended a national planning workshop. Air pollution from fires used to manage ecosystems is an issue in many parts of the country. Land managers are rapidly expanding the use of fire for managing ecosystems, while air resource...AuthorsDavid V. Sandberg, Colin C. Hardy, Roger D. Ottmar, J.A. Kendall Snell, Ann Acheson, Janice L. Peterson, Paula Seamon, Peter Lahm, Dale WadeKeywordsSourceGen. Tech. Rep. PNW-GTR-450. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 60 pYear1999
- This paper presents the historic trends and future projections of forest, farm, and urban land uses for the Lake States of Michigan, Minnesota, and Wisconsin. Since the 1950s, forest and farm land have been decreasing, and urban and other land uses have been increasing throughout the Lake States. Forest, crop, and pasture land have decreased in the region by 3.2, 5.4, and 4.0 million acres, respectively, whereas urban and other land uses have increased by 2.1 and 10.3 million acres, respectively. These decreases and increases were most pronounced during the 1950s and 1980s. Land trends and...AuthorsThomas E. Mauldin, Andrew J. Plantinga, Ralph AligSourceRes. Pap. PNW-RP-519. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 24 pYear1999