Treesearch

Fire scar and stand cohort records were used to estimate the number and timing of fire disturbance events that impacted riparian and adjacent sideslope forests in the Douglas-fir series. Data were gathered from 49 stream segments on 24 separate streams on the east slope of the Washington Cascade Range. Upslope forests had more traceable disturbance events than riparian forests in each of the valley types with a mean difference of 8 to 62%. Approximately 55 to 73% of the total traceable fire disturbance for a stream segment occurred on either sideslope and 24 to 27% in the riparian forest....

Anabat bat detection systems record ultrasonic bat calls on cassette tape by using a sophisticated ultrasonic microphone and cassette tape interface. This paper describes equipment setup and some maintenance issues. The layout and function of display panels are presented with special emphasis on how to use this information to troubleshoot equipment problems. The maintenance section describes opening the equipment, identifying an internal battery, removing panels for maintenance, reinstalling a dislodged light sensor, replacing a broken switch, constructing and replacing a critical battery...

Economic value of commercial, recreational, and tribal fishing is one measure of the importance of fisheries in the interior Columbia River basin (the basin) but only part of the values associated with fish of that region. The basin historically has provided substantial intraregional anadromous stock fisheries and contributes to interregional fisheries along the entire west coast of the United States and Canada. Harvest management, construction of dams and irrigation facilities, changes in habitat, and other factors have led to significant declines in some stocks of fish, thereby diminishin...

Populations of Pacific salmon (Oncorhynchus spp.) in southeast Alaska and adjacent areas of British Columbia and the Yukon Territory show great variation in biological characteristics. An introduction presents goals and methods common to the series of reviews of regional salmon diversity presented in the five subsequent chapters. Our primary goals were to (1) describe patterns of intraspecific variation and identify specific populations that were outliers from prevailing patterns, and (2) evaluate escapement trends and identify potential risk factors confronting salmon populations. We...

Urban areas (cities, towns, villages, etc.) cover 3.5 percent of the 48 conterminous states and contain more than 75 percent of the population. urban areas, about 3.8 billion trees cover 27.1 percent of the land. On a broader scale, metropolitan areas (urban counties) cover 24.5 percent of the conterminous United States and contain 74.4 billion trees that cover 33.4 percent of these counties. Between 1950 and 1990, metropolitan areas nearly tripled in size; urban areas doubled in size over the past 20 to 25 years. This report is the first national assessment of urban forest resources in...

The land area required for a marker-aided selection (MAS) program to break-even (i.e., have equal costs and benefits) was estimated using computer simulation for coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in the Pacific Northwestern United States. We compared the selection efficiency obtained when using an index that included the phenotype and marker score with that obtained using only the phenotype. It was assumed that MAS was restricted to within-family selection, that the rotation age was 50 years, and that growth rate (h2 = 0.25), tree form (h2 = 0.25), and (or) wood...

Secondary plant succession and the accumulation of biomass and nutrients were documented at seven ruminant exclosures in Abies and Pseudotsuga forests variously disturbed by logging, burning, and grass seeding. Long-term (25 or more years) foraging by Rocky Mountain mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus) suppressed the development of deciduous shrubs. Ruminant herbivores influenced vegetation to extents equal to those of the initial episodic disturbances. Food preferences of elk were linearly correlated with long-term development of plant taxa. Accumulations...

Studies were made to determine how long Douglas-fir pollen remains viable after suspension in cool water form 0 to 34 days. Linear regression analysis of in vivo and in vitro tests indicated that filled seed efficiency and pollen viability, respectively, decreased about 3 percent per day. The relation may have been nonlinear the first 6 days, as little decrease occurred during that time. An in vitro test of the effect of none, one, or two drying cycles on previously wetted pollens revealed a great decrease in pollen viability after just one drying cycle. The in vivo test of 1-, 2-, and...

Much is known about the ecological effects, economics, and social impacts of clearcutting, but little documented experience with other silvicultural systems exists in southeast Alaska. The Pacific Northwest Research Station and the Alaska Region of the USDA Forest Service have cooperatively established an interdisciplinary study of ecosystem and social responses to alternative silvicultural systems to evaluate their ability to provide for sustainable wood production and protection of other forest values. This information is needed to select appropriate systems for managing old-growth...

Earthworms are key components of many terrestrial ecosystems; however, little is known of their ecology, distribution, and taxonomy in the eastern interior Columbia River basin assessment area (hereafter referred to as the basin assessment area). This report summarizes the main issues about the ecology of earthworms and their impact on the physical and chemical status of the soil. The three main ecological types of earthworms found in the basin assessment area are epigeic, endogeic, and anecic. Each type has a different life history pattern, resource requirement, and ecological function....