Treesearch

The forest and agriculture sectors are linked by having a portion of their land bases suitable for use in either sector. A substantial part of the southern land base is suitable for either forestry or agriculture use, with most of forestation on U.S. agriculture land in the South. We examine how land exchanges between forestry and agriculture are influenced by specific federal conservation and farm support policies, including changes in the Conservation Reserve Program. Reallocation of land is a significant part of the sectors' responses to the policies, along with intensification of...

Research interest in the forests of Alaska can be traced from the 1990s back to 1741, when Georg Steller, the surgeon on Vitus Bering's Russian expedition, visited Kayak Island, collected plants, and recorded his observations. Given the scope and scale of potential research needs and relatively high expenses for travel and logistics in Alaska, support for forest research in Alaska, from this first European contact through the present era of scientists working with the U.S. Department of Agriculture, Forest Service, seldom was adequate. Forest Service scientists at Juneau, Fairbanks, and...

New silvicultural prescriptions for ecosystem management on both public and private timberlands in western North America will likely result in an influx of relatively small-diameter sawtimber for processing. Since sawmills currently process a majority of sawtimber harvested in western North America (more than 80% in some regions), this study concentrated on determining the value of small-diameter sawtimber delivered to sawmills. Data were collected during the summer of 1997 to describe a representative random-length sawmill and a representative stud mill for the inland region of the United...

It is commonly expected that self-thinning will maintain small-diameter stands at near-normal densities and allow dominant trees to grow reasonably well. Such self-thinning did not occur in the unthinned plots in a thinning study in the Methow Valley of northern Washington, even though there was some suppression-caused mortality. A shift from suppression-caused mortality to insect-caused mortality took place when quadratic mean diameters (QMDs) reached 7 inches. Thinning to spacings wider than 9.3 feet reduced growth of both basal area and cubic volume per acre but greatly in-creased...

Ectomycorrhizal fungi (EMF) consist of about 5,000 species and profoundly affect forest ecosystems by mediating nutrient and water uptake, protecting roots from pathogens and environmental extremes, and maintaining soil structure and forest food webs. Diversity of EMF likely aids forest ecosystem resilience in the face of changing environmental factors such as pollution and global climate change. Many EMF are increasing in commercial value and gathered both as edible fruiting bodies and for production of metabolites in an emerging biotechnical industry. Concerns over decline of EMF have...

Wind disturbance plays a fundamental role in shaping forest dynamics in southeast Alaska. Recent studies have increased our appreciation for the effects of wind at both large and small scales. Current thinking is that wind disturbance characteristics change over a continuum dependent on landscape features (e.g., exposure, landscape position, topography). Data modeling has revealed the existence of distinct wind disturbance regimes, grading from exposed landscapes where recurrent, large-scale wind events prevail to wind-protected landscapes where small-scale canopy gaps predominate....

Two measures of stumpage prices and timber volumes from individual National Forests have been compiled for the Pacific Northwest Region, USDA Forest Service. The first measure is the price and volume of timber sold (1984-96) for the major species for each National Forest. The second measure is the price and volume of timber harvested (1988-96) from individual National Forests. Several price-related issues are discussed including seasonality in the data, the role of prices in monitoring market activity, and the impact of the recent drop in Forest Service timber sales.

Characteristics of an outbreak of the Douglas-fir tussock moth (Orgyia pseudotsugata (McDunnough)) in 1991-95 on the Burns Ranger District of the Malheur National Forest (eastern Oregon) are given and compared with an earlier infestation in the same area in 1963-65. Results of monitoring with pheromone traps, evaluating populations by sampling larvae, and predicting trends and defoliation are reported in detail for the latest outbreak. Temporal patterns of each outbreak also are described and compared with the classic behavior of other tussock moth outbreaks. Findings of this analysis, and...

The impact of increasing the number of crosses per parent (k) on the efficiency of roguing seed orchards (backwards selection, i.e., reselection of parents) was examined by using Monte Carlo simulation. Efficiencies were examined in light of advanced-generation Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) tree improvement programs where information is available from previous generations, seed orchards have reduced genetic variation as a result of selection, and dominance variation is small compared with additive variation. Both the efficiency of reselection and its associated...

Forest carnivores in the Pacific Northwest include 11 medium to large-sized mammalian species of canids, felids, mustelids, and ursids. These carnivores have widely differing status in the region, with some harvested in regulated furbearer seasons, some taken for depredations, and some protected because of rarity. Most large carnivores have declined in numbers or range from human encroachment, loss or modification of forest habitat, accidental deaths (e.g., mortality from vehicles), illegal kills, and our inability to adequately monitor and protect populations. Efforts to reverse these...