Treesearch

Once found throughout the Rocky Mountains and forests of the northern states, the lynx now hides in pockets of its former range while feeding mostly on small animals like snowshoe hares. A team of government and university scientists review the newest scientific knowledge of this unique cat's history, distribution, and ecology. The chapters on this web site provide information for current scientific and public debates regarding the fate of the lynx in the United States. Chapters look at the relationships among lynx, its habitat, and its prey. The attributes of northern versus southern lynx...

An apparatus and method for the moisture content measurement of compressible materials using pressure to firmly hold surface probes against the marerial to be measured. The apparatus uses moisture measurement circuitry employed in frequency domain impedance or time domain reflectometry devices to obtain moisture content readings from materials. These moisture content readings are based on the apparent dielectric constant of the measured material. Subsurface air voids or gaps found in loose layered materials undesirably influence moisture measurement readings by reducing the apparent...

Prescribed fire is used as a site treatment after timber harvesting. These fires result in spatial patterns with some portions consuming all of the forest floor material (duff) and others consuming little. Prior to the burn, spatial sampling of duff thickness and duff water content can be used to generate geostatistical spatial simulations of these characteristics. Results from field studies indicated that spatial patterns of duff characteristics occurred, and they were then modeled by kriging, simulation and a trend-surface modeling techniques. The higher elevations of the study unit...

The subgenus Tridentatae of Artemisia (Asteraceae: Anthemideae) is composed of 11 species of various taxonomic and geographic complexities. It is centered on Artemisia tridentata with its three widespread common subspecies and two more geographically confined ones. Meiotic chromosome counts on pollen mother cells and mitotic chromosome counts on root tips were made on 364 populations (X = 3.1 plants per population). These population counts are ~60% of all Tridentatae counts. Some are first records for taxa. The Tridentatae are a polyploid complex (x = 9) with ploidy levels from 2x to 8x,...

We collected 2,665 hr of behavioral information using video surveillance on 19 Mexican Spotted Owl (Strix occidentalis lucida) pairs between 25 April and 26 July 1996. Prey deliveries per day increased as the nesting season progressed, with an average of 2.68 prey deliveries during incubation, 4.10 items during brooding, and 4.51 items during the nestling phase. The highest delivery rates were concentrated between l-3 hours before sunrise (02:00-05:00) and l-3 hours after sunset (18:00-21:00). Trip duration during diurnal hours increased 14 fold from incubation through the nestling phase,...

This report stems from Congressional concern over the equivalency between Federal payments to counties containing Federal resource management lands, the likely tax liability, and other county-level benefits and costs associated with those lands. Results indicate that the overall tax liability on Federal lands is almost three times the Federal payments. A survey of county executive officers indicates that the direct fiscal costs or benefits to county governments from Federal lands and programs are modest.

Long-term monitoring of ecological and hydrological processes is critical to understanding ecosystem function and responses to anthropogenic and natural disturbances. Much of the world's knowledge of ecosystem responses to disturbance comes from long-term studies on gaged watersheds. However, there are relatively few long-term sites due to the large cost and commitment required to establish and maintain them. Knowledge gained from these sites is also important for predicting responses to future disturbances, such as climatic change, and these sites should be the focal point for the...

This paper investigates an optimization approach to determining the placement and timing of habitat protection for the western prairie fringed orchid. This plant’s population dynamics are complex, creating a challenging optimization problem. The sensitivity of the orchid to random climate conditions is handled probabilistically. The plant’s seed, protocorm and above-ground stages are all accounted for in a case example from the Sheyenne National Grassland in North Dakota. Sensitivity of the case example model to dispersal assumptions and climate condition probabilities is demonstrated.

An online bibliography was compiled to furnish a literature basis for implementing of land management activities and planning research endeavors in the Madrean Biogeographic Province, which includes the Madrean Archipelago region in the southwestern United States. Citations are listed alphabetically by author in categories appropriate to the subject-matter presented. The large number of citations preclude hard-copy publication. The complete bibliography is available on the USDA Forest Service, Rocky Mountain Research Station's Flagstaff office web site at www.rmrs.nau.edu/publications/madre...

Forest scientists ask that everyone, from the home gardener to the forest manager, help revive western white pine by planting it everywhere, even in nonforest environments such as our neighborhood streets, parks, and backyards. White pine, long ago considered the "King Pine," once dominated the moist inland forests of the Northwest, eventually spawning whole industries and historical movements. Now-since the arrival of Euro-Americans and the stubborn blister rust disease-this sun-loving giant barely survives on about 5 percent of its former domain. This is the story of the decline of the...