Treesearch

Sand lance (Ammodytes) constitute a major prey for at least some populations of over 100 species of consumer, including 40 species of birds, 12 species of marine mammals, 45 species of fishes, and some invertebrates. Variation in the availability of sand lance (and other forage fishes) can have major effects on the breeding success and survival of their predators. Commercial fishing and other pressures on sand lance populations potentially have ramifying effects on many species of wildlife.

Diameter increments for individual trees increased curvilinearly and stand basal area increments decreased curvilinearly as spacing increased from 6.6 to 26.4 feet. Average height growth of all trees increased linearly, and stand cubic volume growth decreased linearly as spacing increased. Large differences in tree sizes developed over the 35 years of study with various spacing treatments. Plots without understory grew more during the first 20 years of study but soil quality decreased. During the last 15 years, growth rates on plots without understory were not superior to plots with...

Forestry policy, planning, and practice have changed rapidly with implementation of ecosystem management by federal, state, tribal, and private organizations. Implementation entails new concepts, terminology, and management approaches. Yet there seems to have been little organized effort to obtain feedback from on-the-ground managers on the practicality of implementing ecosystem management. We convened a colloquium in Forks, WA, in 1997 to assess the state of ecosystem management. We used a recent interagency modeling exercise to formulate six concepts and questions to present to small...

Alaska based on the literature and the author's experience. Storm winds resulting in damage to forest stands are described, and some ecological and management considerations of wind that are of concern to forest managers are reviewed. The author made a general reconnaissance of forest conditions on Prince of Wales Island and adjacent islands based on forest-type maps, aerial photographs, and ground and air checks. Forest conditions associated with blowdown are described and are discussed.

This proceedings contains contributions from each author or group of authors who presented their current research at the bark beetle genetics workshop held 17-18 July 1998 on the campus of the University of Wisconsin in Madison, Wisconsin, USA. This was the second meeting on this subject; the first was held in 1992. The subject of bark beetle genetics is of growing, international interest; researchers from Austria, Hungary, and Mexico, as well as from across the United States have contributed to this proceedings. The topics covered included molecular approaches to genetic analysis of bark...

This paper reviews the methodology used to derive the original estimates for direct employment associated with recreation on Federal lands in the interior Columbia River basin (the basin), and details the changes in methodology and data used to derive new estimates. The new analysis resulted in an estimate of 77,655 direct-effect jobs associated with recreational activities on Federal lands in the basin. This estimate is a little over one-third of the previous estimate. The new estimated direct-effect recreational jobs amount to 4.48 percent of the total estimated jobs in the basin in...

We hypothesized that the relative availability of meat, indicated by contribution to the diet, would be positively related to body size and population productivity of North American brown, or grizzly, bears (Ursus arctos). Dietary contributions of plant matter and meat derived from both terrestrial and marine sources were quantified by stable-isotope analysis (ä3C and ä15N) of hair samples from 13 brown bear populations. Estimates of adult female body mass, mean litter size, and population density were obtained from. two field studies of ours and from other published reports. The population...

This paper examines the costs of meeting explicit targets for increments of carbon sequestered in forests when both forest management decisions and the area of forests can be varied. Costs are estimated as welfare losses in markets for forest and agricultural products. Results show greatest change in management actions when targets require large near-term flux increments, while land area change is largest when long-term increments are needed, Marginal costs per tonne of carbon flux do not vary greatly with the form of the target and are similar to findings of earlier studies for comparable...

Land use planning often is implemented to control development on forests and farmland, but its impact on land use remains untested. Previous studies evaluating such programs have relied on anecdotal evidence rather than on data describing actual land use change. A model of land use is specified as a function of socioeconomic factors, land rent, and landowners' characteristics, to examine how well Oregon's land use planning program has protected forests and farmland from development. The empirical model describes the probability that forests and farmland in western Oregon and western...

Provides current information on lumber and plywood production and prices; employment in the forest industries: international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies: and other related items.