Treesearch

The following management tools can help meet multiple values—environmental, economic, and aesthetic—when used collectively and according to a well-devised plan. Cavity Tree Creation Coarse Woody Debris Augmentation Underplanting Conservation of Biological legacies Variable-Density Thinning Extended Harvest Rotations

Thinning and retention of biological legacies (large live, dead, and fallen trees and their associated biota) during clearcutting are two practices to promote development of late-seral attributes in second-growth forests. We evaluated the effects of these practices on production of truffles and use of truffles as food by northern flying squirrels and Townsend’s chipmunks in 55-65-yr-old Douglas-fir forests in the Puget Trough of Washington. Truffles were collected at 6-wk intervals from March 1993 through December 1995. Feces were collected from flying squirrels and chipmunks in fall and...

A stand-replacement prescribed fire in an over-mature lodgepole pine (Pinus contorta Dougl. ex Loud.)-subalpine fir (Abies lasiocarpa (Hook.) Nutt.) stand (snag area) and in a mature lodgepole pine thicket (thicket area) resulted in lower plant diversity within the first year after burning, and as fire energy outputs increased, postburn plant cover and diversity decreased. There was no reestablishment of the original plant cover where total heat output exceeded 100 000 kcal/m2. Apparently, most plants in this habitat were not fire resistant. Postfire recovery appears to depend on immigratio...

Greefihouse-induced warming and resulting shifts in climatic zones may exceed the migration capabilities of some species. We used fourteen combinations of General Circulation Models (GCMs) and Global Vegetation Models (GVMs) to investigate possible migration rates required under CO2 doubled climatic forcing.

Small-log utilization or thinning operations followed by a fuel treatment such as prescribed fire can be used to change the composition and structure of fuelbeds, thereby mitigating deleterious fire effects and reducing the potential for catastrophic wildfires in some forested landscapes. We are developing a national system, Fuel Characteristic Classification (FCC), for fuel identification and assessment that accurately depicts the structural complexity and geographical diversity of all fuelbeds including those manipulated by humans. The FCC system can be used to easily assess the effective...

The ventilation climate information system (VCIS) allows users to access risks to values of air quality and visibility from historical patterns of ventilation conditions.

almon runs in the Pacific Northwest have been declining for decades, so much so that many runs are threatened or endangered; others have been completely extirpated (Nehlsen et al. 1991). This "salmon crisis" looms large in the public eye, because it has serious and wideranging economic, cultural, and ecological repercussions. Billions of dollars have gone into industrial and agricultural projects that alter regional rivers in ways that, often unintentionally, make them inaccessible or unsuitable for salmon. Recently, billions more have been spent in largely unsuccessful attempts to restore...

Randomly located transects were used to assess visual soil disturbance on eight units in the Fritz Timber Sale, Colville National Forest. Equipment trails, mostly designated, accounted for about 25 percent of the total area. The cut-to-length harvester and forwarder combination with 130-foot trail spacing produced the least visual disturbance. Leaving slash on trails appeared to reduce displacement and rutting. Rehabilitation of trails, landings, and temporary roads could move seven of the eight units toward compliance with regional standards for detrimental disturbance. Validation of...

Balsam woolly adelgid (BWA) is an introduced insect that has had a significant impact on Abies tree species in the Pacific Northwest. During the late 1950s and 1960s, it caused extensive mortality of grand fir (A. grandis), subalpine fir (A. lasiocarpa), and silver fir (A. amabilis), particularly in the Cascade Range. This insect also affects tree growth and reproduction, potentially decreasing host generation and the role of the host tree in local ecosystems.

In the last decade, Swiss needle cast (SNC), caused by the native fungus Phaeocryptopus gaeumannii, has severely damaged Douglas-fir in the Coast Range of western Oregon. The primary impact of the pathogen on Douglas-fir (the only susceptible tree species) is premature loss of foliage, which results in significant reduction in tree growth. Recent reduction in volume growth from SNC in western Oregon likely exceeds 100 million board feet per year.