Treesearch

Regression equations are presented for estimating biomass of five western hardwoods: red alder (Alnus rubra Bong.), giant chinkapin (Castanopsis chrysophylla (Dougl.) A. DC.), bigleaf maple (Acer macrophyllum Pursh), Pacific madrone (Arbutus menziesii Pursh), and tanoak (Lithocarpus densiflorus (Hook. & Arn.) Rehd.). Estimators are given for total crown biomass, cumulative proportions for separating crown weight into foliage and four timelag fuel diameter classes, bark weight, and bole volume (inside bark) to any specified top diameter. With one exception, the equations use diameter at...

A survey in the Blue Mountains of north-eastern Oregon and southeastern Washington showed that, on the average, partial cuts in the grand fir/big huckleberry community were well stocked with a mixture of advance, natural post-harvest, and planted reproduction of a number of species. Partial cuts in the mixed conifer/pinegrass community had considerably fewer seedlings; some plots were understocked. Much of the understocking appeared to be related to low and irregular overstory density, lack of advance reproduction, reproduction destroyed by logging, and heavy grass cover.

Twenty-two forages from Admiralty Island, southeastern Alaska, were monitored bimonthly for one year to assess seasonal changes in their chemical composition: neutral detergent fiber, acid detergent fiber, cellulose, lignin/cutin, invitro dry-matter digestibility, total nitrogen, phosphorus, potassium, calcium, magnesium, sodium, copper, manganese, iron, and zinc. Seasonal fluctuations were pronounced but generally paralleled the pulse of plant growth in spring-summer. Only minor differences were found in chemical composition of forages from two study areas and results of this study did...

Logging-damage surveys and tree-dissection studies were made in commercially thinned, naturally established young-growth true fir stands in the Lassen National Forest in northern California. Significant damage occurred to residual trees in stands logged by conventional methods. Logging damage was substantially lower in stands thinned using techniques designed to reduce injuries from felling and skidding. A total of 243 wounded white and red firs in 11 stands were felled, dissected, and analyzed for decay. All wounds were infected by decay fungi. Decay losses associated with wounds were 6.8...

A growth-simulation model for central Oregon lodgepole pine (Pinus contorta Dougl.) has been constructed by combining data from temporary and permanent sample plots. The model is similar to a conventional yield table with the added capacity for dealing with the stand-density variable. The simulator runs on a desk-top computer.

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...