Treesearch

The elevated intensity of wildfire seasons in the American West combined with political, environmental, and economic issues surrounding the use of coal and oil are spurring a growing interest in the use of woody biomass as a fuel for heating and electrical generation. David Nicholls, a forest products technologist at the Alaska Wood Utilization Research and Development Center in Sitka, along with his colleagues, have researched the feasibility of using woody biomass from many angles: the potential supply of wood; the economics of gathering, transporting, and processing it; the use of...

The marbled murrelet (Brachyramphus marmoratus) is a seabird in the family Alcidae that forages in nearshore waters of the Pacific Northwest, and nests in adjacent older-forest conifers within 80 km offshore. The species is of conservation concern due to habitat loss and declining numbers, and is listed as Threatened in British Columbia, Canada and in the United States portion of its range south of Canada. Recent monitoring in the United States indicated that murrelet numbers continued to decline there, especially in the waters of Washington State. To better understand this decline, and to...

Interactions between ecological disturbances have the potential to alter other disturbances and their associated regimes, such as the likelihood, severity, and extent of events. The influence of exposure to wind and yellow cedar decline on the landslide regime of Alaskan temperate rainforests was explored using presence-only modeling techniques. The wind regime was found to be a significant influence on the spatial distribution of landslide events. This effect was mediated by slope, with little interactive effects at low angles and stronger influences on steeper slopes. Mechanistically,...

Federal agencies are mandated to measure, manage, and reduce greenhouse gas (GHG) emissions. The General Services Administration (GSA) Carbon Footprint Tool (CFT) is an online tool built to utilize measured GHG inventories to help Forest Service units streamline reporting and make informed decisions about operational efficiency. In fiscal year 2013, the Forest Service Sustainable Operations GHG Tracking Team completed GHG inventories of three Forest Service units to compare top-down (national) and bottom-up (local) inventory reporting approaches. In this report, the Track to Zero Team...

This report investigates the interactions between household location decisions and community characteristics, including green space. Household location decisions are a primary driver of land-use change, and collective location decisions affect community characteristics. At the same time, community characteristics affect location decisions. Neighborhoods or communities that have well-managed green space programs are more attractive to residents, a two-way interaction that tends to be self-reinforcing. Communities with high amenities and public services attract high-income residents,...

Stress in trees is caused by disturbances such as fire, flood, disease, or insect infestations. A single stressor may not be enough to kill a tree, but a combination can be deadly. Tree tissues produce and accumulate ethanol in response to many stressors. Ethanol provides the stressed tissues with an emergency energy source when their normal source of energy from aerobic respiration is impaired by stressors. Many insects, including various bark and ambrosia beetles, can detect ethanol. If the stressed tree releases enough ethanol into the atmosphere, it serves as a signal, attracting the...

Developing forest lands and agricultural lands for other uses has wide-ranging implications. Land development can affect production from forest and agricultural lands, wildlife habitat quality, the spread of invasive species, water quality, wildfire control, and infrastructure costs. In its attempts to mitigate these effects, Oregon implemented statewide land-use planning laws in the early 1970s. Washington established less prescriptive laws in the 1990s. Policymakers, land managers, and various interest groups want to know the effect these laws have had on land use. Scientists with the...

Height and diameter growth of noble fir (Abies procera Rehd.) trees included in the largest 40 stems per acre were compared in a study that included five precommercial thinning spacings plus no thinning, in each of eight replications, at elevations from 2,200 to 4,100 feet in the western Cascade Mountains of Washington and Oregon. Height growth rates were not affected by spacing. The unthinned treatment had slightly greater initial heights, a difference that probably arose from the method used to select leave trees in thinning. Height trends differed markedly from those given in Herman et...

Seed zones and seed transfer guidelines describe where plants are most likely to thrive. Scientists with the Forest Service and Agricultural Research Service undertook a 9-year project to build empirical seed zones for bluebunch wheatgrass, a foundational native grass throughout the West. The research will help the Forest Service and Bureau of Land Management accelerate restoration of native grasses and combat invasive species such as cheatgrass. Scientists documented variation in bluebunch populations, looking particularly at traits important for adaptation to drought and cold. Forest...

Do qualitative classifications of ecological conditions for harvesting culturally important forest plants correspond to quantitative differences among sites? To address this question, we blended scientific methods (SEK) and traditional ecological knowledge (TEK) to identify conditions on sites considered good, marginal, or poor for harvesting the leaves of a plant (beargrass; Xerophyllum tenax) used in tribal basket weaving. We relied on voluntary participation of six expert weavers, a stratified, randomized field sample, discriminant analysis (DA), a standardized color system, and paired...