Treesearch

The significant geographic extent of lodgepole pine (Pinus contorta) in the interior West and the large proportion within the mixed-severity fire regime has led to efforts for more ecologically based management of lodgepole pine. New research and demonstration activities are presented that may provide knowledge and techniques to manage lodgepole pine forests in the interior West. First, at the stand and watershed levels, a current application of a suite of restoration treatments to lodgepole pine stands within a watershed in central Montana is discussed. Second, a Bitterroot Ecosystem...

The Rocky Mountains and Southwestern United States, essentially the Colorado River Basin, have been the focus of a wide range of research efforts to learn more about the effects of natural and human induced disturbances on the functioning, processes, and components of the regions’s ecosystems. Watershed research, spearheaded by the USDA Forest Service and its cooperators, leads to a better understanding of the regions’s ecology, and to the formulation of management guidelines to meet the increasing needs of people living in these regions and throughout the Western United States. This paper...

Watershed management, an ancient concept, was defined in Vedic texts from India that date from 1,000 B.C. This concept has been an integral part of forest and rangeland management in North America throughout the 20th century, but its scope has broadened significantly. Although the Forest Reserve Act of 1891 created the reserves that were to become the core of the National Forest System, it was the Pettigrew Amendment to the 1897 Sundry Civil Appropriations Bill that defined the purpose of the forest reserves. The amendment stated that the reserves could be established only to “...improve...

Soil quality standards and guidelines of the USDA Forest Service were some of the first in the world to be developed to evaluate changes in forest soil productivity and sustainability after harvesting and site preparation. International and national development of criteria and indicators for maintenance of soil productivity make it imperative to have adequate threshold variables within the USDA Forest Service. In the Pacific Northwest, soils range from fine-textured Andisols to coarse-textured skeletal Inceptisols. Forest types encompass the highly productive coastal rain forest to...

The Wilderness Act of 1964, which established the National Wilderness Preservation System, contains both a clear definition of wilderness and multiple “nonconforming” exceptions to this definition. Managers are given discretion to manage these nonconforming uses but must do so within the framework of wilderness the Act sought to preserve. This paper presents a process for assessing congressional intent by closely examining both the legislative language and the legislative history. This process is based on the works of legal scholars, case law and judicial practice. The paper then demonstrat...

This paper provides a brief overview of the Southwestern Borderlands Ecosystem Management Research Project. Much of the research program was described in more detail, along with results thus far, in a conference presented in January 1999. Conference proceedings are documented by Gottfried and others (1999). The focus of the project is research on restoring natural processes, improving the productivity of grasslands and woodlands, providing wildlife habitat, and sustaining an open landscape, viable rural economy, and social structure.

"Historical range of variability" and "reference conditions" are two concepts that attempt to characterize ecosystem conditions as they may exist in the absence of pervasive human impacts. However, to define reference conditions from reference landscapes, such as U.S. Forest Service Research Natural Areas, requires a long-term perspective by which to assess whether existing ecosystem conditions are driven by predominately natural rather than human factors. We used fire-scarred trees to reconstruct centuries-long chronologies of surface fires in four research natural areas (three established...

A method is described for predicting the spatial distribution of individual birds using presence data. The approach is demonstrated using a statistical habitat association model developed for resident and migratory birds on a 12 ha plot of ponderosa pine (Pinus ponderosa) heavily infested with southwestern ponderosa pine dwarf mistletoe (Arceuthobium vasinatum subsp. Cryptopodum (Englemann) Hawksworth and Weins). Bird locations and densiometer readings of canopy opening were recorded on a 5 m´5 m sampling grid. Minimum threshold theory was used to fit a logistic regression model to the...

Species richness of local communities is a state variable commonly used in community ecology and conservation biology. Investigation of spatial and temporal variations in richness and identification of factors associated with these variations form a basis for specifying management plans, evaluating these plans, and for testing hypotheses of theoretical interest. However, estimation of species richness is not trivial: species can be missed by investigators during sampling sessions. Sampling artifacts can lead to erroneous conclusions on spatial and temporal variation in species richness....

The idea that local factors govern local richness has been dominant for years, but recent theoretical and empirical studies have stressed the influence of regional factors on local richness. Fewer species at a site could reflect not only the influence of local factors, but also a smaller regional pool. The possible dependency of local richness on the regional pool should be taken into account when addressing the influence of local factors on local richness. It is possible to account for this potential dependency by comparing relative species richness among sites, rather than species...