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- A number of chemicals of diverse characteristics have arbitrarily been classed together on the basis of their use and given the descriptive name "pesticides." An unfortunate aura of mystery has developed about these chemicals. However, there is nothing unique or mysterious about the chemicals we refer to as "pesticides." Like other chemicals, they have properties which can be accurately measured; they obey all the laws of physics, chemistry, and biology. Chemical and physical properties of a pesticide and interacting environmental factors determine the behavior of pesticides. Behavior in...AuthorsLogan A. NorrisKeywordsSourceGen. Tech. Rep. PNW-GTR-019. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 10 pYear1974
- The extent of water-dependent log handling and storage facilities in southeast Alaska is summarized, along with the available literature on the environmental impact of these facilities. Field studies were conducted at 16 sites and correlated with laboratory studies of leaching rates and toxicity of the four major wood species harvested in southeast Alaska. Significant effects on water quality are believed to occur only under unique conditions and were observed at only 2 of the 16 study sites. Bark deposits with a high demand for oxygen were observed at all active and abandoned log dumping...AuthorsBruce C. PeaseKeywordsSourceGen. Tech. Rep. PNW-GTR-022. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 58 pYear1974
- The evaluation of timber access road alternatives is one of the primary tasks in timber harvest planning and design. During the planning stages, it is also one of the most difficult to accomplish quantitatively because a basis for comparison is related to such values as grade, length, horizontal and vertical curvature, and volumes of excavation and embankment. Within reasonable time constraints, these values are almost impossible to produce with any accuracy. Evaluating several alternatives is usually out of the question.The analysis of timber access road alternatives involves four...AuthorsDoyle BurkeSourceGen. Tech. Rep. PNW-GTR-027. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 40 pYear1974
- This report presents a general overview of factors relevant to the productive and safe use of helicopters for timber harvesting, with emphasis on candidate helicopters and their characteristics.AuthorsP.M. Stevens, Edward H. ClarkeSourceGen. Tech. Rep. PNW-GTR-020. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 16 pYear1974
- Results are reported of a preliminary investigation of feasibility of using wood residue to meet energy and raw material needs in the Pacific Coast States. Magnitude of needs was examined and volume of logging-residue and unused mill residue was estimated. Costs of obtaining and preprocessing logging residue for energy and pulp and particle board raw material were estimated and compared with selling values of mill residue fuel, pulp chips, and particle board. Marginally feasible energy use seemed best suited for inplant steam and power production by the wood industry, Although raw material...AuthorsJohn B. Grantham, Eldon Estep, John M. Pierovich, Harold Tarkow, Thomas C. AdamsSourceGen. Tech. Rep. PNW-GTR-018. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 37 pYear1974
- Large-scale use of the timber resource of southeast Alaska began in 1953 after long efforts to establish a timber industry. Development and present status of the industry and present management of the timber resource are summarized, stressing the biological basis for timber management activities in southeast Alaska today. Ecological and silvicultural considerations related to timber harvest, reforestation, and stand development are discussed. Published and unpublished information are brought together. Current management practices are discussed as a basis for a better understanding of how...AuthorsArland S. Harris, Wilbur A. FarrKeywordsSourceGen. Tech. Rep. PNW-GTR-025. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 116 pYear1974
- The latest inventory of the timber resources of the Inland Empire area of Washington indicates there are 24 billion board feet of sawtimber on 3.9 million acres of commercial forest land. Public agencies administer about 56 percent of the area and 70 percent of the sawtimber volume, farmer and miscellaneous private ownerships account for 37 percent of the area but only 22 percent of the sawtimber volume, and industry 8 percent of the total commercial forest area and 8 percent of the volume. Douglas-fir is the most abundant species, accounting for 30 percent of the sawtimber volume....AuthorsHal A. ArbogastKeywordsSourceRes. Bull. PNW-RB-050. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 68 pYear1974
- One of the most striking characteristics of southeast Alaska is the abundance of water. Large glaciers, icefields, and thousands of streams result from heavy precipitation throughout the year. Published and unpublished data on water regimen, temperature, sedimentation, and chemistry are combined. These serve as a basis for understanding how this valuable resource may be used and protected so that high quality water may always be abundant and available. A brief section on needed research is included.AuthorsDonald C. Schmiege, Austin E. Helmers, Daniel M. BishopKeywordsSourceGen. Tech. Rep. PNW-GTR-028. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 32 pYear1974
- The disease problems of old growth are largely being taken care of by cutting. This same cutting is rapidly converting large areas of old growth to reproduction and young growth. It is in these areas of young growth that our disease problems will most probably arise. With a few exceptions the reproduction and young-growth stands appear quite healthy at this time with the diseases that are present just doing a bit of natural thinning. These new stands should be closely studied. Damage appearing in young stands may be due toor may be corrected bycertain silvicultural practices...AuthorsThomas H. LaurentKeywordsSourceGen. Tech. Rep. PNW-GTR-023. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 36 pYear1974
- Research in southeast Alaska has identified soil mass movement as the dominant erosion process, with debris avalanches and debris flows the most frequent events on characteristically steep, forested slopes. Periodically high soil water levels and steep slopes are controlling factors. Bedrock structure and the rooting characteristics of trees and other vegetation exert a strong influence on relative stability of individual sites. Timber harvesting operations have a major impact on initiation and acceleration of these movements. The cutting of timber itself has been directly linked with...AuthorsDouglas N. SwanstonKeywordsSourceGen. Tech. Rep. PNW-GTR-017. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 27 pYear1974