Treesearch

Forty-two species of insects and mites found on Taxusare discussed, including all those known to occur in North America, of which 27 occur in western North America. Thirty-eight species are phytophagous, and 28 of these have sucking, rather than chewing, mouth parts. It is suggested that some of the chemical compounds present in the foliage of different species Taxus select against chewing insects and favor fluidfeeding arthropods.

This assessment focuses on the regional and community economies of southeast Alaska. A mixed economy composed of subsistence harvest and cash income characterizes the economies of most of the region’s rural communities. Although the share of natural resource-based sectors relative to total employment has remained fairly consistent over the past 10 years, the mix of industries within that share is shifting, with substantial declines in the wood products sector and substantial increases in the recreation-tourism sector. Regional trends are reflected very differently across boroughs, and even...

On degraded subalpine range in Utah, the authors examined the role of soil and parent material nutrients and organic carbon (Corg) in the development of soil and plants on a transect across six strata that formed visible concentric alternating bands of high and low productivity. Relations for soil and parent material phosphorus (P) and sulfur (S) were of particular interest. Odd-numbered strata displayed visibly lower amounts of surface rock cover and greater vegetative cover than even-numbered strata. Data suggest that S of the parent material may play a key role in the development of...

The H.J. Andrews Experimental Forest is a world renowned center for research and education about the ecology and management of forests and streams. Located about 50 miles (80 km) east of Eugene, Oregon, the Andrews Experimental Forest lies in the Blue River Ranger District of the Willamette National Forest. Established in 1948, the Experimental Forest is administered cooperatively by the USDA Forest Service’s Pacific Northwest Research Station, Oregon State University, and the Willamette National Forest. Funding for the research and education programs comes from the National Science...

An analysis of lumber prices provided regressions for price trends during the period 1971-95 for composite lumber grades of major timber species found in the Pacific Northwest west of the crest of the Cascade Range. The analysis included data for coastal Douglas-fir and hem-fir lumber; coastal and inland Pacific Northwest ponderosa, sugar, and western white pines; and inland Pacific Northwest and Rocky Mountain lodgepole pine. Future prices of grades by species group are based on these price trends and the latest average regional lumber values established in the Timber Assessment Market...

Aspects of climate that influence air quality in the Columbia River basin of the Northwestern United States are described. A few, relatively simple, analytical tools were developed to show the spatial and temporal patterns of mean-monthly mixing heights, precipitation scavenging, upper level and surface trajectory winds, and drought that inhibit pollution uptake. Also, potential changes in air quality from the effects of increasing greenhouse gases are discussed.

Fifteen years of research on old-growth and managed coniferous forests have provided sufficient understanding of biodiversity to suggest a basis for ecosystem management. First, natural old forests have a metaphysics values associated with their existence and function can never be addressed fully with the scientific method alone; we cannot recreate old growth. Second, five processes underly forest development: crown-class differentiation, decadence, canopy stratification, understory development, and development of habitat breadth. Habitat breadth results from fine scale spatial heterogeneit...

Export constraints affecting North American west coast logs have existed intermittently since 1831. Recent developments have tended toward tighter restrictions. National, Provincial, and State rules are described.

This report present information on biogeography and broad-scale ecology (macroecology) of selected fungi, lichens, bryophytes, vascular plants, invertebrates, and vertebrates of the interior Columbia River basin and adjacent areas. Rareplants include many endemics associated with local conditions. Potential plant and invertebrate bioindicators are identified. Species ecological functions differ among communities and variously affect ecosystem diversity and productivity. Species of alpine and subalpine communities are identified that may be at risk from climate change. Maps of terrestrial...

Big shifts have been made over the last decade in how society thinks forest lands should be managed. Forest policy has subsequently changed. Land managers now grapple with how to make society's intentions work in the forests of today.This issue of PNW Science Findings presents the Colville study's examination of the vast forests of small-diameter wood in the intermountain West. In this region, land managers are working to decrease the risk to forest health from fire, insects, and disease while improving wildlife habitat and aesthetics. In doing so, they are considering how to create the...