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A computer program, FIRES: Fire Information Retrieval and Evaluation System, provides methods for evaluating the performance of fire danger rating indexes. The relationship between fire danger indexes and historical fire occurrence and size is examined through logistic regression and percentiles. Historical seasonal trends of fire danger and fire occurrence can be plotted and compared. Methods for defining critical levels of fire danger are provided. The paper includes a review of NFDRS philosophy and application, a description of input and output, and a summary of fire danger rating...

Classification trees and linear regression analysis were used to build models to predict probabilities of infestation and amount of tree mortality in terms of basal area resulting from roundheaded pine beetle, Dendroctonus adjunctus Blandford, activity in ponderosa pine, Pinus ponderosa Laws., in the Sacramento Mountains, New Mexico. Classification trees were built for combined habitat types sampled and for each habitat type series or type sampled. Cross-validation estimates of classification accuracy ranged from 0.64 to 0.79. The data suggest that stands attacked by the roundheaded pine...

Ecological units are described at the subsection level of the Forest Service National Hierarchical Framework of Ecological Units. A total of 91 subsections are delineated on the 1996 map "Ecological Units of the Northern Region: Subsections," based on physical and biological criteria. This document consists of descriptions of the climate, geomorphology, geology, vegetation, and soils that characterize each subsection. Included is information on sources of natural disturbances, current land use, and ecological relationships of the major components.

Biological control of pest Bruchidae may provide an important management strategy against infestation of stored grain legumes, a key source of dietary protein in developing countwies. Previous related research has focused on the potential of parasitoids to contwol bruchids; the role of generalist predators in this application has not yet been extensively explored.

On 20 September 1995 at 11:15 MST, during routine mist-netting for a study investigating the use of the middle Rio Grande riparian habitat by migratory land birds at Rio Grande Nature Center, Bernalillo County, New Mexico, we were surprised to discover a light yellowish warbler in one of the nets. After careful examination and comparison, the bird was identified as a hatching-year (by incomplete skull ossification) Wilson's Warbler with albino plumage. The sex was not determined.

We studied timing, abundance, subspecies composition, fat stores, stopover length, and habitat use of Willow Flycatchers (Empidonax traillii) during spring and fall stopover along the Middle Rio Grande, New Mexico. Spring migration started in mid-May and lasted about a month. Fall migration started in early-August and also lasted about a month. The most abundant subspecies was the Southwestern Willow Flycatcher (E. t. extimus), followed by E. t. brewsteri, E. t. adastus, and E. t. traillii. Nearly half of the Willow Flycatchers captured had no observable fat. Spring flycatchers had more...

Using standardized mist-netting capture data from the Rio Grande Nature Center, Albuquerque, New Mexico from 1985-1994, and Breeding Bird Survey data from New Mexico and United States from 1980-1994, we compared local, regional, and national population trends of landbird species that migrate along the middle Rio Grande in fall. Evaluations of relationships among population trends, migratory distance, breeding habitat use, nest type, and foraging guilds revealed that population trends of Rio Grande migrants were relatively species-specific and that population changes were unequally distribut...

Vegetation of the alpine zone of eight mountain ranges in southwestern Montana was classified using IWINSPAN, DECORAN, and STRATA-algorithms embedded within the U.S. Forest Service Northern Region's ECADS (ecological classification and description system) program. Quantitative estimates of vegetation and soil attributes were sampled from 138 plots. Vegetation composition, structure, productivity, associated soil features, and landscape positions are described for the 23 recognized community types that include wetland, snowbed, cushion plant, turf, and grassland physiognomic types. Field...

Andisols support ≈ 200 000 ha of mid-elevation grand fir (Abies grandis [Dougl. ex D.Don] Lindl.) forests in the Pacific Northwest region that are characterized by little or no natural conifer regeneration following removal of the forest canopy. Previous work suggests that the properties of these Andisols have been altered as a result of the establishment of successional communities dominated by bracken fern (Pteridium aquilinum [L.] Kuhn) in deforested areas. In this study, we compared soil properties in a 30-yr-old bracken fern site (clear-cut in 1965), a natural bracken fern site that...

The Butte City Fire occurred on July 1, 1994, west of Idaho Falls, ID. Ignited from a burning flat tire, the blaze was driven by high winds that caused it to cover over 20,500 acres in just over 6.5 hours. Sagebrush (Artemisia tridentata ssp. wyomingensis) is the principal shrub species of this high desert rangeland. With the absence of vegetation after the fire, erosion increased tremendously. Because the fire occurred on the Idaho National Engineering Laboratory, researchers were able to gather weather information from remote meteorological stations positioned on and around the site.