Treesearch
Search National Treesearch
Displaying 3,561 - 3,570 of 6,856 Publications
- Population growth in Oregon, Washington, and Alaska is expected to increase demand for outdoor recreation on public land. This trend will be tempered by changes in the sociodemographic composition of the population. Among sociodemographic characteristics, different ages and incomes correspond to different participation rates. Although older Americans are participating more, participation is still lower among this group for active pursuits. Hence, as the population ages, demand for passive activities may increase. Low-income people participate at a much lower rate than higher income people...AuthorsTroy E. Hall, Heather Heaton, Linda E. KrugerKeywordsSourceGen. Tech. Rep. PNW-GTR-778. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 108 pYear2009
- Forests of the Pacific Northwest have been an epicenter for the evolution of truffle fungi with over 350 truffle species and 55 genera currently identified. Truffle fungi develop their reproductive fruit-bodies typically belowground, so they are harder to find and study than mushrooms that fruit aboveground. Nevertheless, over the last five decades, the Corvallis Forest Mycology program of the Pacific Northwest Research Station has amassed unprecedented knowledge on the diversity and ecology of truffles in the region. Truffle fungi form mycorrhizal symbioses that benefit the growth and...AuthorsJames M. Trappe, Randy Molina, Daniel L. Luoma, Efren Cázares, David Pilz, Jane E. Smith, Michael Castellano, Steven L. Miller, Matthew J. TrappeKeywordsSourceGen. Tech. Rep. PNW-GTR-772. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 194 p.Year2009
- The primary objectives of the study were to characterize the critical properties of wood flour produced using highly deteriorated beetle-killed spruce for wood-plastic composite (WPC) production and evaluate important mechanical and physical properties of WPC extruded using an industry standard formulation. Chemical composition analysis indicated no significant differences in wood constituents between highly deteriorated and sound wood. Preliminary investigation with Fourier transform infrared spectroscopy (FTIR), however, indicated partial degradation or depolymerization of carbohydrate...AuthorsV. Yadama, Eini C. Lowell, N. Petersen, D. NichollsSourcePolymer Engineering and Science. 49(1): 129-136Year2009
- This synthesis examines international opportunities for utilizing biomass for energy at several different scales, with an emphasis on larger scale electrical power generation at stand-alone facilities as well as smaller scale thermal heating applications such as those at governmental, educational, or other institutional facilities. It identifies barriers that can inhibit bioenergy applications, and considers international cases of successful bioenergy production with a focus on Europe and Brazil. Based on the review of international bioenergy applications, important ecosystem service...AuthorsD.L. Nicholls, R. Monserud, D. DykstraKeywordsSourceForest Ecology and Management 257(8): 1647-1655Year2009
- Log moisture content has an important impact on many aspects of log home construction, including log processing, transportation costs, and dimensional stability in use. Air-drying times for house logs from freshly harvested trees can depend on numerous factors including initial moisture content, log diameter, bark condition, and environmental conditions during drying. In this study, we evaluated air-drying properties of young-growth Sitka spruce (Picea sitchensis (Bong.) Carr) and of western hemlock (Tsuga heterophylla (Raf.) Sarg.) from logs harvested in southeast Alaska. For each...AuthorsDavid L. Nicholls, Allen M. BrackleyKeywordsSourceGen. Tech. Rep. PNW-GTR-782. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 18 pYear2009
- The Vegetation Diversity and Structure Indicator (VEG) is an extensive inventory of vascular plants in the forests of the United States. The VEG indicator provides baseline data to assess trends in forest vascular plant species richness and composition, and the relative abundance and spatial distribution of those species, including invasive and introduced species. The VEG indicator is one of several sets of measures collected by the Forest Inventory and Analysis (FIA) Program of the USDA Forest Service to assess forest health. This document describes the sampling design, field data...AuthorsBethany K. Schulz, William Bechtold, Stanley J. ZarnochKeywordsSourceGen. Tech. Rep. PNW-GTR-781. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 53 pYear2009
- Removing dams that are outdated, unsafe, or pose significant economic or environmental costs has emerged in the last 10 years as a major river restoration strategy. The removal of the 45-foot-high Marmot Dam on the Sandy River in 2007 resulted in the biggest sediment release accompanying any dam removal to date. It also provided an unprecedented opportunity for a team of scientists from the Pacific Northwest Research Station and other organizations to predict, monitor, and evaluate the river environment before, during, and after the event. The dam removal was successful on many levels. The...AuthorsNoreen Parks, Gordon GrantKeywordsSourceScience Findings 111. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 5 pYear2009
- This report highlights significant research findings and accomplishments by scientists at the Pacific Northwest (PNW) Research Station during fiscal year 2008. The mission of the PNW Research Station is to generate and communicate scientific knowledge that helps people understand and make informed choices about people, natural resources, and the environment. The work featured in this report illustrates the breadth and the depth of research underway that enables the station to accomplish this mission and deliver timely information to those in the management and policy arenas.AuthorsRhonda MazzaKeywordsSourcePortland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 89 pYear2009
- Timber harvest following wildfire leads to different outcomes depending on the biophysical setting of the forest, pattern of burn severity, operational aspects of tree removal, and other management activities. Fire effects range from relatively minor, in which fire burns through the understory and may kill a few trees, to severe, in which fire kills most trees and removes much of the organic soil layer. Postfire logging adds to these effects by removing standing dead trees (snags) and disturbing the soil. The influence of postfire logging depends on the intensity of the fire, intensity of...AuthorsDavid L. Peterson, James K. Agee, Gregory H. Aplet, Dennis Dykstra, Russell T. Graham, John F. Lehmkuhl, David S. Pilliod, Donald F. Potts, Robert F. Powers, John D. StuartSourceGen. Tech. Rep. PNW-GTR-776. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 51 pYear2009
- Wood has become an important energy alternative in Alaska, particularly in rural areas where liquid fuel costs can be substantial. In some cases, wood fuel is readily available to communities, increasing the attractiveness of wood energy. Wood energy systems in rural Alaska can also lead to employment gains as well as benefits to local cash economies. Many Alaska villages are now considering wood as a fuel source for community heating, several have completed feasibility studies, and others are moving forward with design and construction activities. Cordwood is readily available in many...AuthorsDavid L. Nicholls, Tom MilesSourceGen. Tech. Rep. PNW-GTR-783. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 17 p.Year2009