Treesearch

Factors for adjusting wind velocities from the 20-foot standard anemometer height down to an average wildfire midflame height (3.5 ft for the fuels studied) are given for exposed, partially sheltered, and sheltered fuels in Alaska. The values are suitable for predicting wildfire behavior.

Bighorn sheep were once abundant throughout Western North America. Since 1900, however, they have declined in most areas and many populations have been eliminated. Population declines have been attributed to hunting, to parasites and disease, and to competition with domestic livestock for forage, and with humans for space. Wildlife agencies in the western regions of Canada, the United States, and Mexico have initiated programs to maintain or enhance existing populations of bighorn sheep and to reintroduce them into historic ranges. But unless there is better land management, a decline of 8...

This report summarizes a 1980 timber resource inventory of the 16 forested counties in Washington east of the crest of the Cascade Range. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

This Symposium was planned by members of the IUFRO Site Group (S1.02) as part of their on-going activities to facilitate the worldwide exchange of ideas among individual research workers and to promote the dissemination of research results in the area of forest site productivity. The Symposium consisted of three days of indoor sessions followed by a 2-1/2-day field trip through the forests of western Washington, including the Mt. St. Helens blast zone. The Symposium attracted 130 participants from 15 countries. Acknowledgments are made to members of the Symposium planning committee: Stan...

The forest vegetation of 3,600,000 hectares in northeast interior Alaska was classified. A total of 365 plots located in a stratified random design were run through the ordination programs SIMORD and TWINSPAN. A total of 40 forest communities were described vegetatively and, to a limited extent, environmentally. The area covered by each community was similar, ranging from 0.29 to 4.29 percent. A large number of mixed spruce communities were described and suggested to be the result of the study area’s proximity to the northern limit of black spruce (Piceamariana (Mill.) B.S.P.). Average...

Results are reported for three studies that dealt with the influence of timber sale practices on competition for timber in the timber-dependent communities of Medford and Grant County An Oregon and those surrounding the Nezperce National Forest in Idaho. Results are also reported for a fourth study that examines how several firms managed their uncut volume under contract. Although the description of the various local economies is only indicative of others, these studies point out the fragile nature of the economies of timber-dependent communities where most jobs, wages, and government...

U.S. Department of Agriculture regulations permit departures from current National Forest timber harvesting policies when "implementation of base harvest schedules.., would cause a substantial adverse impact upon a community .... " This paper describes the kinds of information needed for forest managers to adequately assess the relevance of the departure issue to particular planning units. The relevance of the departure issue varied, depending on: (1) future timber supply, (2) timber dependency, (3) the long-term feasibility of alternatives to current timber harvesting schedules, and (4)...

Investigations of the ecological behavior of fishes often require studies in both natural and artificial stream environments. We describe a large, recirculating stream aquarium and its controls, constructed for ecological studies at the Forestry Sciences Laboratory in Corvallis.

This paper provides estimates of bird density, diversity, and evenness on 13 clearcut units of the Siuslaw National Forest in the Coast Ranges of Oregon, sampled during 1979,1980, and 1981. Total density of nesting birds ranged from 322 to 588 per 40.5 hectares (100 acres); there were 15 to 19 species nesting on each site.

Herbicides, insecticides, fertilizers, and fire retardants are chemicals used to protect or enhance certain forest resources. Their use may directly affect anadromous fish by exposing them to toxic amounts of the chemical. Indirect effects are also possible through chemically induced alteration of habitat, including direct effects on fish-food organisms.Data on the movement, persistence, and toxicity of chemicals provide a basis for evaluating potential direct effects of chemical use on fish and fish-food organisms. Data are included for seven herbicides (2,4-D, picloram, atrazine, MSMA,...