Treesearch

A taper equation and associated tables are presented for red alder (Alnus rubra Bong.) trees grown in plantations. The data were gathered from variable-density experimental plantations throughout the Pacific Northwest. Diameter inside bark along the stem was fitted to a variable exponent model form by using generalized nonlinear least squares and a first-order continuous autoregressive process. A number of parameterizations of the exponent were examined in a preliminary analysis, and the most appropriate form was determined. This was achieved by examining alternative models across geographi...

This report examines the growth and development of the tourism industry in Hoonah, Alaska, and its effects on community life and resource use. The report describes the gradual development of tourism in Hoonah and presents resident perceptions of tourism’s effect on the natural and social environment. A multisited ethnographic approach was used featuring indepth, open-ended interviews with local residents, tourism providers, business owners, and government officials. Data were analyzed using Ethnograph, a software program used to assist in coding data based on prominent themes. Results...

We studied the movement patterns of migratory coastal cutthroat trout Oncorhynchus clarkii clarkii in the western Copper River delta, Alaska, near the northern extent of the subspecies' distribution. Life history information for coastal cutthroat trout is scarce within this region. Movement of coastal cutthroat trout was monitored from 1994 to 1996 with radiotelemetry and tag-recapture of fish at a two-way fish weir. Radiotracking of 20 adults was conducted for a period ranging from 5 to 343 d. We observed anadromous and potamodromous migrations by fish that were morphologically indistingui...

Many former Oregon white oak woodland and savanna stands in the coastal Pacific Northwest have been invaded and subsequently overtopped by Douglas-fir during the past century. We examined soil water and microclimate conditions near overtopped oak trees and near oak trees that had been released from Douglas-fir. In each of the three study years, volumetric soil water content declined from ~25 percent to ~10 percent during the early-to-mid growing season near all trees, but this decline was delayed approximately 1 month in the released condition. Throughfall from May through July was...

Thinning of 30- to 70-year-old Douglas-fir (Psuedotsuga menziesii [Mirb.] Franco) stands is a common silvicultural activity on federal forest lands of the Pacific Northwest, United States. Empirical relationships among riparian functions, silvicultural treatments, and different riparian buffer widths are not well documented for small headwater streams. We investigated buffer width and density management effects on ripairan microclimates of headwater streams in Oregon. Spatial variations in stand density, canopy cover, and microclimate were measured along transects extending from stream...

Management of riparian habitats is controversial because land use policies have historically emphasized economic values (e.g., timber production) at the expense of ecological and social values. Attempting to manage these valuable resources to attain the greatest combination of benefits has created a long-term controversy that continues to the present. Our analysis indicates that at mid to large spatial scales, healthy riparian ecosystems and land management activities are not mutually exclusive, but the degree of compatibility is determined by policy decisions based on competing demands...

The marbled murrelet (Brachyramphus marmoratus) ranges from Alaska to California and is listed under the Endangered Species Act as a threatened species in Washington, Oregon, and California. Marbled murrelet recovery depends, in large part, on conservation and restoration of breeding habitat on federally managed lands. A major objective of the Northwest Forest Plan (the Plan) is to conserve and restore nesting habitat that will sustain a viable marbled murrelet population. Under the Plan, monitoring is an essential component and is designed to help managers understand the degree to which...

Abstract: The Fuel Characteristic Classification System (FCCS) includes equations that calculate energy release and one-dimensional spread rate in quasi-steady-state fires in heterogeneous but spatially uniform wildland fuelbeds, using a reformulation of the widely used Rothermel fire spread model. This reformulation provides an automated means to predict fire behavior under any environmental conditions in any natural, modified, or simultated wildland fuelbed. The formulation may be used to compare potential fire behavior between fuelbeds that differ in time, space, or as a result of...

This study explored the use of state and transition models (STMs) to evaluate the effects of natural disturbances and land-use practices on aquatic and riparian habitats. The probability of stand-replacing wildfires, underburns, grazing, floods, and debris flows were used to define historical and current disturbance regimes. Model runs illustrated dramatic changes in riparian vegetation, channel conditions, and habitat suitability for anadromous salmonids resulting from changes in disturbance regimes following Euro-American settlement. Limitations in the use of STMs and their potential...

The extent of Oregon white oak woodland and savanna ecosystems in the Pacific Northwest has diminished significantly during the past century, and planting of Oregon white oak seedlings is often necessary for restoring these plant communities. Our objective was to evaluate the effects of tree shelters, control of competing vegetation, fertilization, irrigation, and planting date on seedling growth and survival. Although survival rates were generally high, solid-walled tree shelters increased mean annual height growth. Plastic mulch increased soil water content and height growth. Controlled-r...