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- Land evaluations are not always conducted with adequate understanding of the relevant geologic and climatic contexts and their appropriate scales. This understanding is essential for developing representative sampling, monitoring, and conservation designs, and for pooling results of landscape analysis. To provide context for several regions of the interior northwestern United States, we conducted an ecoregion classification of the interior Columbia River Basin and vicinity (‘the Basin’). We grouped land units that are influenced by the same higher order geology and landform features, and...AuthorsP.F. Hessburg, R.B. Salter, R.B. Richmond, B.G. SmithSourceApplied Vegetation Science. 3: 163-180Year2000
- A comparison of historic and current stand structure and species composition was made in Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa) forest series on the eastern slopes of the Cascade Mountains. We used tree ring analysis of 1,192 tree cores from the Okanogan National Forest to reconstruct historical tree diameter and inferred structural attributes during the past 100 years. Sampled stands currently have more trees per acre and more basal area than were found historically. Overall stand density has increased 307% for Douglas-fir, 81% for ponderosa pine and 138%...AuthorsPeter Ohlson, Richard SchellhaasSourceUnpublished ReportYear2000
- Researchers at the Pacific Northwest Research Station have completed over 100 forest product recovery studies over the past 40 years. Tree, log, and product data from these studies have been entered into a database, which will allow further analysis within, between, and across studies. Opportunities for analysis include stand-to-log-to-final product estimates of volume, quality, and value. Examples of possible database queries include determining the variation in recovery volume and product yield from different age or diameter classes, the relation between percentage of sound log volume...AuthorsJames A. Stevens, R. James BarbourKeywordsSourceRes. Note PNW-RN-528. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 9 pYear2000
- A classification of community types, successional sequences, and landscapes is presented for the piedmont of the Copper River Delta. The classification was based on a sampling of 471 sites. A total of 75 community types, 42 successional sequences, and 6 landscapes are described. The classification of community types reflects the existing vegetation communities on the landscape. The distribution, vegetation composition and structure, soils, and successional status of each community are discussed. The community types were placed within successional sequences reflecting their successional...AuthorsKeith BoggsKeywordsSourceGen. Tech. Rep. PNW-GTR-469. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 244 pYear2000
- In 1998, forest vegetation was monitored for ozone injury on permanent plots in two Sierra Nevada national forests in California, at three locations in Mount Rainier National Park in Washington, and at 68 forest health monitoring (FHM) locations throughout Washington, Oregon, and California. This was the first year that extensive monitoring of forest vegetation for ozone injury was carried out in Oregon and Washington. Injury was detected on ponderosa and Jeffrey pine in the Sierra Nevada permanent plots and on red elderberry at one FHM location in southwest Washington. No injury was...AuthorsSally Campbell, Gretchen Smith, Pat Temple, John Pronos, Regina Rochefort, Chris AndersenKeywordsSourceGen. Tech. Rep. PNW-GTR-495. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 19 pYear2000
- We describe a protocol and provide a summary for point-count monitoring of landbirds that is designed for habitat-based objectives. Presentation is in four steps: preparation and planning, selecting monitoring sites, establishing monitoring stations, and conducting point counts. We describe the basis for doing habitat-based point counts, how they are organized, and how they differ from other approaches using point counts. We discuss links between local scale and larger scale monitoring and methods to evaluate sample size for monitoring. We develop a framework for identifying potential...AuthorsMark H. Huff, Kelly A. Bettinger, Howard L. Ferguson, Martin J. Brown, Bob AltmanKeywordsSourceGen. Tech. Rep. PNW-GTR-501. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 39 pYear2000
- A purposive social assessment across three communities explored reactions of local residents to wildfires in the Wenatchee National Forest in north-central Washington. Research concentrated on identifying the diversity of fundamental beliefs and values held by local residents about wildfire and forest management. Particular emphasis was given to investigating community social structures and potential conflict dynamics surrounding fire recovery efforts. Semistructured interviews were conducted with people representing a diverse set of values, attachments to the National Forest, and beliefs...AuthorsMatthew S. Carroll, Angela J. Findley, Keith A. Blatner, Sandra Rodriguez Mendez, Steven E. Daniels, Gregg B. WalkerKeywordsSourceGen. Tech. Rep. PNW-GTR-479. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 114 pYear2000
- For the past ten years, Douglas-fir on the Oregon and Washington coast has shown a progressive decrease in height and diameter increment as a result of Swiss needle cast, which is caused by Phaeocryptopus gaeumannii. In this contribution, we discuss the effects of silvicultural operations on Swiss needle cast and recommend specific actions to reduce the severity of the disease. We also suggest a method of assessing the severity of Swiss needle cast damage to a stand based on years of needle retention. Our recommendations are based on disease severity and are designed to discriminate...AuthorsGregory M. Filip, A. Kanaskie, K. Kavanagh, G. Johnson, R. Johnson, D. MaguireSourceResearch Contribution 30. Corvallis, OR: Forest Research Laboratory, Oregon State University. 20 pYear2000
- We developed the landscape age-class demographics simulator (LADS) to model historical variability in the amount of old-growth and late-successional forest in the Oregon Coast Range over the past 3,000 years. The model simulated temporal and spatial patterns of forest fires along with the resulting fluctuations in the distribution of forest age classes across the landscape. Parameters describing historical fire regimes were derived from data from a number of existing dendroecological and paleoecological studies. Our results indicated that the historical age-class distribution was highly...AuthorsM.C. Wimberly, T.M. Spies, C.J. Long, C. WhitlockKeywordsSourceConservation Biology. 14(1): 167-180Year2000
- Ecological management of second-growth forest holds great promise for conservation of biodiversity, yet little experimental evidence exists to compare alternative management approaches. Wintering birds are one of several groups of species most likely to be influenced by forest management activities. We compared species richness and proportion of stand area used over time by wintering birds in 16 second-growth Douglas-fir (Pseudotsuga menziesii) stands to determine the effects of management strategy and experimental variable-density thinnings. Management strategies were retaining legacies...AuthorsB. Haveri, A.B. CareyKeywordsSourceWildlife Society Bulletin. 28(3): 643-652Year2000