Treesearch

Fire suppression associated with decades of cattle grazing can result in bush encroachment in savannas. Textural analyses of historical, high resolution images was used to characterize bush densities across a South African study landscape. A control site, where vegetation was assumed to have changed minimally for the duration of the image record (1955-1996), was used to standardize textural values between multidate images. Standardized textural values were then converted to estimates of percent woody canopy cover using a simple linear regression model. Results indicate a 30% relative...

This study describes the trip and visitor characteristics, evaluations, and preferences of day users in wilderness, by contrasting them with overnight users. Data from the Three Sisters (OR), Desolation (CA), Bob Marshall (MT), Charles Deam (IN), Caney Creek (AR), Shining Rock (NC), and Cohutta (GA) Wildernesses are presented. Primary conclusions were that: (1) day users and overnight users are not profoundly different; (2) day users are more tolerant of relatively crowded conditions and less likely to see an immediate need to limit use (at least in places that receive substantial day...

Bromus tectorum L. (cheatgrass or downy brome) is an important exotic weed in natural ecosystems as well as in winter cereal cropland in semiarid western North America. The systemic, seedling-infecting head smut pathogen Ustilago bullata Berk. commonly infects cheatgrass stands, often at epidemic levels. We examined factors controlling U. bullata infection levels in greenhouse studies with parental lines of four B. tectorum populations from contrasting habitats and U. bullata bulk teliospore collections from within the four populations. The U. bullata infection process appeared to have...

Geographic Information Systems (GIS) are increasingly being used in all areas of natural resource management. This paper first presents a brief primer on GIS, and then discusses potential applications of GIS to wilderness management in the areas of inventorying, monitoring, analysis, planning, and communication. Outlined are the limitations and pitfalls that could compromise the effectiveness of a wilderness GIS, and several suggestions are included for improving the chances of successfully using GIS in wilderness management.

This annotated reading list provides an introduction to the issue of recreation fees on public lands. With an emphasis on wilderness recreation fees, this compilation of historical and recent publications is divided into the following sections: historical context, arguments for and against fees, pricing mechanisms and the effects of price, public attitudes toward fees, the influence of fees on recreation visitation and use patterns, and methods to estimate fee revenue and determine priorities for expenditures.

The workshop was convened to assess progress and offer further ideas regarding scientific contributions to (1) understanding relationships between visitor use density and wilderness experiences and (2) applying such knowledge to decisions about use limitation in wilderness and parks. The first paper provides an overview of the topic and the papers presented at the workshop. Subsequent papers include reviews of previous research, discussion of issues related to use limitation, exploration of the solitude concept and of visitor conflict, and explications of alternative research methodologies.

We present an annotated bibliography that provides information on and reference to the literature on outdoor recreation use valuation studies. This information is presented by study source, benefit measures, recreation activity, valuation methodology, and USDA Forest Service region. Tables are provided that reference the bibliography for each activity, enabling easy location of studies. The literature review spans 1967 to 1998 and covers 21 recreation activities plus a category for wilderness recreation. There are 163 individual studies referenced, providing 760 benefit measures. Guidelines...

Opportunities for unique visitor experiences are among the defining attributes of wilderness. In order to understand and protect these experiences, natural and social scientists have pursued an ever-expanding program of wildland recreation research. While much of the early research sought to identify simple relationships between setting attributes and visitor experiences, recent research efforts have expanded to address the values people hold for wilderness (including nonrecreation values), a variety of types and dimensions of wilderness experiences, and factors that influence those...

Landscape assessment and planning often depend on the ability to predict change of vegetation. This report compares four modeling systems (FETM, LANDSUM, SIMPPLLE, and VDDT) that can be used to understand changes resulting from succession, natural disturbance, and management activities. The four models may be useful for regional or local assessments in National Forest planning rules. Although these models are limited in their ability to support site-specific decisionmaking, they can prove helpful in understanding and comparing strongly differentiated alternatives. They can also be used to...

Although forest health may be difficult to define and measure, a strong demand exists for assessment of forest conditions at various state, regional, and national scales. Forest Health Monitoring (FHM) is a national program designed to measure the status, changes, and trends of forest conditions annually. This report presents a broad view of forest health issues affecting the Interior West region of Montana, Idaho, Wyoming, Utah, Nevada, Colorado, New Mexico, and Arizona. We found that the forests of the Interior West have changed considerably in the past century. What is more difficult to...