Treesearch

Squirrel communities simultaneously composed of abundant populations of Glaucomys, Tamias, and Tamiasciurus are: (1) a result of high production of seeds and fruiting bodies by forest plants and fungi and complexity of ecosystem structure, composition, and function; (2) indicative of high carrying capacity for vertebrate predators and (3) characteristic of old, natural forests in the Pacific northwest, USA. I hypothesized that silvicultural manipulation of canopies of second-growth forests could result in spatial heterogeneity that would reproduce the biocomplexity and plant-fungal...

Small mammals have been proposed as indicators of sustainability in forests in the Pacific Northwest and elsewhere. Mammal community composition and species abundances purportedly result from interactions among species, forest-floor characteristics, large coarse woody debris, understory vegetation, and overstory composition. Coarse woody debris is thought to be particularly important because of its diverse ecological functions; covers from 10 to 15% have been recommended based on retrospective studies of forests and small mammals. Unfortunately, ecological correlations are not necessarily...

We hypothesized that creating a mosaic of interspersed patches of different densities of canopy trees in a second-growth Douglas-fir (Pseudotsuga menziesiz) forest would accelerate development of biocomplexity (diversity in ecosystem structure, composition, and processes) by promoting spatial heterogeneity in understory, midstory, and canopy, compared to typical managed forests. In turn, increased spatial heterogeneity was expected to promote variety in fine-scale plant associations, foliage height diversity, and abundance of small mammals. Three years following treatment, understory...

Managing second-growth forests to conserve biodiversity has been proposed by both foresters and conservation biologists. Management, however, can have unintended consequences, including reduction in native species diversity and increased invasion by exotic species. Our goal was to determine if inducing heterogeneity in managed forest canopies could promote a diversity of native species without contributing markedly to invasion by exotic species. We examined 1- and 3- year responses of understory plants to variable-density thinning of 55- to 65-year-old stands of Pseudotsuga menziesii...

This paper examines the socioeconomic effects of alternative management strategies for Forest Service and Bureau of Land Management lands in the interior Columbia basin. From a broad-scale perspective, there is little impact or variation between alternatives in terms of changes in total economic activity or social conditions in the region. However, adopting a finer scale and examining affects on the counties that are likely to be most impacted by federal lands management reveals that many of these counties may be better off under one alternative in the short term, but better off under...

Significant changes over the past 150 years in aquatic, terrestrial, landscape, and socioeconomic systems have altered biophysical systems in the interior Columbia basin. Changes and conflict in public policy concerns, such as resource use vs. restoration vs. conservation are especially evident in more than 34% of total forest and rangeland in the United States that are federally administered. In the last decade, design and implementation of complex land management strategies has become an issue for public land managers. In turn, the scientific community is often challenged to develop...

Knowledge of the survival of the Pileated Woodpecker (Dryocopus pileatus) is essential in managing viable populations of the species. In eight study areas in northeastern Oregon, survivorship of adult Pileated Woodpeckers was 0.60 after 6 mo, 0.47 after 12 me, and 0.35 after 18 mo. Of three juveniles radio-tagged in late summer or fall, two survived to breed the next year. Of 13 juveniles radio-tagged as nestlings, 23-54% survived 3.5 mo. In these populations adult mortality exceeded recruitment of young into the breeding population. Survival may have been influenced by transmitter...

The abundance of birds and amphibian larvae was compared between fenced and unfenced stock ponds in 1993 to determine if fencing improved the habitat for these species in northeastern Oregon. Stock ponds that were fenced had significantly higher densities of bird species, guilds, and taxonomic groups than stock ponds that were unfenced. No differences in the relative abundance of larvae of Pacific treefrogs (Pseudacris regilla) or long-toed salamanders (Ambystoma macrodactylum) were found between fenced and unfenced ponds. Fencing at least a portion of stock ponds in forested areas...

Summary estimates are presented of forest resource area, timber volume, and growth and mortality of timber on unreserved national forest land in the Chatham inventory unit of the Tongass National Forest. Pacific Northwest Research Station, Forest Inventory and Analysis crews collected inventory data from 1995 to 2000. Productive forest land area (timberland) was estimated at 1,302 thousand acres, cubic-foot volume on timberland at 7,561 million cubic feet, and net annual growth and mortality at 31,613 and 28,341 thousand cubic feet, respectively.

While many people interested in natural resources management propose science-based decisions, it is not clear what “science-based” means. Science-based decisions are those that result from the full and complete consideration of the relevant science information. We offer five guidelines to focus the scientist’s contributions to science-based decisionmaking and use the experience of using science in the development of natural resource management decisions for the Tongass National Forest and for the federal lands in the interior Columbia River basin as examples to illustrate our guidelines.