Treesearch

We evaluated the potential of two novel thermally enhanced Landsat Thematic Mapper (TM)-derived spectral indices for discriminating burned areas and for producing fire perimeter data (as a potential surrogate to digital fire atlas data) within two wildland fires (1985 and 1993) in ponderosa pine (Pinus ponderosa) forests of the Gila Wilderness, New Mexico, USA. Image-derived perimeters (manually produced and classified from an index image) were compared to fire perimeters recorded within a digitized fire atlas. For each fire, the highest spectral separability was achieved using the newly...

The production of residual white ash patches within wildfires represents near-complete combustion of the available fuel and releases a considerable quantity of gases to the atmosphere. These patches are generally produced from combustion of large downed woody debris (LDWD) such as fallen trees and snags. However, LDWD are generally ignored in calculations of fuel combusted within environments where surface fires dominate (e.g. southern African savannas). To assess the potential of fractional white ash cover as a remotely sensed measure of LDWD combustion, both the proportion of the surface...

Although fuel reduction treatments are widespread, there is great variability and uncertainty in the cost of conducting treatments. Researchers from the Rocky Mountain Research Station, USDA Forest Service, have developed a model for estimating the per-acre cost for mechanical fuel reduction treatments. Although these models do a good job of identifying factors that influence the costs of treatments, individual fuel treatments are unique, and the associated costs remain highly variable. Therefore, these cost estimates should only be used as a rough first estimate.Other publications in this...

Crown width measurements collected during Forest Inventory and Analysis and Forest Health Monitoring surveys are being used to develop individual tree crown width models and plot-level canopy cover models for species and forest types in the Intermountain West. Several model applications are considered in the development process, including remote sensing of plot variables and stand modeling with the Forest Vegetation Simulator. The modeling process is intended to be data driven, consistent with crown architecture and stand dynamics concepts, and compatible with multiple end-user applications.

Local, state, and national agencies charged with managing wildlands in the United States are now seeking to learn more about the public's preferences for managing forests. For this reason agency wildland managers are making use of survey research to supplement their public input processes. Agency managers often choose random-digit dial telephone surveys because of the speed and relatively low cost associated with this mode of administration. This paper assesses the accuracy of responses to a question that asks the location of respondents' homes relative to a National Forest boundary. The...

This study compared aspatial and spatial methods of using remote sensing and field data to predict maximum growing season leaf area index (LAI) maps in a boreal forest in Manitoba, Canada. The methods tested were orthogonal regression analysis (reduced major axis, RMA) and two geostatistical techniques: kriging with an external drift (KED) and sequential Gaussian conditional simulation (SGCS). Deterministic methods such as RMA and KED provide a single predicted map with either aspatial (e.g., standard error, in regression techniques) or limited spatial (e.g., KED variance) assessments of...

The period from 1880 to 1900 is regarded as the period of "spoilation" of western rangelands. In Albert Potters own words, "Quick profits and fortunes lead to speculation and incredible numbers of stock were placed upon the range. Cowman was arrayed against sheep man, big owners against small, and might ruled more often than right." The Government took no action until 1891 when the Creative Act established the Forest Reserve system under the Interior Department's General Land Office (GLO). Lacking authority and undermined by political appointees, the GLO foundered until the reserves were...

Evaluating the effects of managing for one forest resource in terms of associated impacts on other resources is not easy. Yet methods to identify potential trade-offs among forest resources are necessary to inform people about the implications of management options on public land. This paper uses a case study from a forest reserve in the northwestern United States to quantify trade-offs between fire threat (FT) and late-seral forest (LSF) structure at stand and landscape levels. Simulation of forest dynamics was done with and without silvicultural treatments. A landscape optimization...

This status report presents the results of 43 permanent forest health study plots (3871 trees, saplings, and seedlings) established in 2000 and 2001 in parts of three areas of the Eastern Arc Mountains - the Taita Hills in Kenya (Ngangao and Chawia), the East Usambara Mountains (Amani Nature Reserve) and the Uluguru Mountains (Morogoro Teachers College and Kimboza) in Tanzania. Three main indicators of forest health - mensuration, visual crown ratings, and tree damage - were collected to provide baseline information on the forested areas. In general, the trees measured are considered...