Treesearch

Growth and structural changes in a mosaic of even-aged ponderosa pine (Pinus ponderosa) stands were studied for 25 years to determine the long-term impacts of a heavy thinning treatment to a basal-area level of 25 ft2/acre. Basal area and volume growth of these stands has increased since thinning and likely will continue to increase as the residual trees increase in size. Furthermore, future stand integrity should be maintained at relatively low-density levels. It is unlikely, however, that timber production could be sustained at this level. A more plausible scenario is to manage the...

The Western United States has a rich heritage of biological diversity within the wilderness areas. To access human disturbances compared to human-undisturbed sites, the tool of “benchmarking” is used, where sites are compared over time. The resulting data and photographic records are the basis of monitoring used by land managers. Examples are given for three locations, as well as details of monitoring techniques.

Focusing on the Southwest but raising questions that are more broadly applicable, we compare ecological restoration with conventional management regimes -- multiple-use management, ecosystem management, and managing for specific resourse objectives. That restoration assumes a holistic prespective and active intervention does not distinguish it from other approaches to achieving ecosystem health. We find that foresters and restorationists both use ecology, but restorationists use a reference condition as a substitute for specific objectives. We believe that restorationists who advocate...

Many catastrophic wildfires burned throughout forests in Arizona during the spring and summer of 1996 owing to severely dry conditions. One result of these fires was a loss of preexisting tree cavities for reproduction. In ponderosa pine (Pinus ponderosa) forests most cavities are found in dead trees; therefore, snags are a very important habitat component for cavity-nesting species. Thls study focused on the impacts of wildfire on bird populations within 3 ponderosa pine forests throughout northern Arizona. We present preliminary results from the first bird breeding season following the...

Efforts to return natural fire to the Gila National Forest, New Mexico, have resulted in controversy regarding management of snags (standing dead trees). The importance of snags for wildlife, especially cavity-dependent birds, is well documented. Although general uses of snags by birds are known (nesting, roosting, perching, and foraging), we know little about the optimal number of snags needed to sustain populations of snag-dependent species. We know less of the types, numbers, sizes, and vigor of snags that would persist under a natural fire regime. Recently, efforts were initiated to...

We examined effects of a varied-severity wildfire on the community structure of small mammals and populations of the 2 most abundant species, the deer mouse (Peromyscus maniculatus) and the gray-collared chipmunk (Tamias cinereicollis), in northern Arizona ponderosa pine (Pinus ponderosa) forests. We examined 2 fire severities and compared them to unburned controls. The average number of species captured was similar among the 3 plot types: 2.0 on high-severity plots, 3.0 on moderate-severity plots, and 3.5 on control plots. However, the species composition differed among these types....

To increase understanding of roosting habitat of Mexican Spotted Owls (Strix occidentalis lucida) and factors that influence use of roosting habitat, we sampled habitat characteristics at 1790 sites used for roosting by 28 radio-marked Mexican Spotted Owls in three study areas in Arizona and New Mexico. We explored potential patterns of variation in roost-site characteristics by estimating similarity among all possible pairs of roost sites and summarizing patterns in these similarity estimates using a linear model. Factors in the model included owl identity and season. We conducted these...

This paper describes the multi-stage public consultation process and other aspects of the development by the Tasmanian Parks and Wildlife Service of the second (1999) management plan for the Tasmanian Wilderness World Heritage Area (Australia). It describes the background to, and rationale for, the process used in developing the plan; it details the consultation process itself; and it critically examines the lessons learned in the course of developing the plan and considers how the effectiveness of such a process can be assessed.

Over the past few decades, numerous studies have investigated relationships between encounters and the backcountry recreation experience. Although academics and professionals may recognize that meeting others in backcountry areas could result in positive interactions that are beneficial to the experience, research directed at the positive aspects of intergroup relations is still in its inception. This paper examines encounters using a symbolic interactionist framework, grounded in empirical data, and provides an interpretation of the inter-linkages between encounters, experiences, and...

I arrived at Los Alamos on May 14, 2000 to conduct an examination of the home destruction associated with the Cerro Grande Fire. My examination occurred between the afternoon of 5/14 and late afternoon on 5/16. I had contact with the southern command post incident management team, the Los Alamos Fire Department, and the Santa Fe National Forest.The homes were destroyed as the main body of the Cerro Grande Fire burned past Los Alamos to the north-northeast and then toward the northeast between about 1700 on 5/10 to the early morning hours of 5/11. About 200 single and multi-family structures...