Life Sciences Commons^™

Restoration Of Aspen Woodland Invaded By Western Juniper: Applications Of Partial Cutting And Prescribed Fire, Jonathon D. Bates, Richard F. Miller

Aspen Bibliography

Western juniper (Juniperus occidentalis spp. occidentalis) woodlands are rapidly replacing quaking aspen (Populus tremuloides) stands throughout the northern Great Basin. Aspen stands provide important habitat for many wildlife species and contain a high diversity of understory shrubs and herbaceous species. We studies two juniper removal treatments to restore aspen woodlands in Kiger Canyon on Steens Mountain, Oregon.

Snow Avalanche Disturbance In Intermountain Spruce-Fir Forests And Implications For The Spruce Bark Beetle (Coleoptera: Scolytidae), Elizabeth G. Hebertson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spruce beetle outbreaks are the primary biotic disturbance affecting forests in the Intermountain spruce-fir zone. Major snow avalanches can produce large quantities of host material for spruce beetle colonization; however, few studies have examined the influence of avalanche disturbance on outbreak initiation. The purpose of my research was to investigate potential relationships between these two disturbance agents. In the first study, I used dendro-ecological analyses to date major avalanche years on the Wasatch Plateau in south-central Utah, and then determined what climate factors were associated with avalanche occurrence. The results indicated that mean January snowfall was significantly related to the …

Quantifying Losses Of Understory Forage In Aspen Stands On The Dixie And Fishlake National Forests, Barton R. Stam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The West has lost up to 60% of its historic aspen stands over the last century, probably as a result of the successional tendency of aspen to be replaced by coniferous species in the absence of periodic fires. One of several major impacts of this change is the loss of understory forage as conifer canopy cover increases. I measured understory biomass in aspen stands ranging from 0% to 81 % absolute conifer cover in the canopy and found that understory production declines exponentially as conifers replace aspen. I also did an economic analysis to determine the value of the forage …

Remote Sensing Of Sagebrush Community Structural Patterns Across Scales, Lisa A. Langs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Throughout the Intermountain West there has been a substantial reduction in both the quantity and quality of sagebrush ecosystems. To assist current range management objectives, numerous efforts have been made to classify and map sagebrush communities using remotely sensed data. However, the amount of detail provided by these broad-scale mapping projects is often limited. This research evaluated the ability of a suite of airborne and satellite imagery to detect sagebrush community structural attributes, specifically percent canopy cover, live cover, density, size-vigor, and spatial arrangement of shrubs. Field data was collected at Camp Williams National Guard Training Facility near Bluffdale, Utah, …

Cougar Exploitation Levels In Utah: Implications For Demographic Structure, Metapopulation Dynamics, And Population Recovery, David C. Stoner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Presently, eleven western states and two Canadian provinces utilize sport hunting as the primary mechanism for managing cougar (Puma concolor) populations. However, the impacts of sustained harvest on population dynamics and demographic structure arc not well understood. Additionally, the lack of cost-effective enumeration techniques and strongly conflicting societal values complicate effective management of this species. Given these concerns, the primary goals of this study were (I) to determine the effects of sustained harvest on cougar populations, and (2) estimate the level and extent of cougar harvest statewide.

I monitored cougar populations on Monroe Mountain in south-central Utah, and …

Greenstrip Establishment And Management In The Intermountain West, Brenda Kristine Younkin-Kury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greenstrips were established at two sites in Utah to determine if seeded, grazed cool-season, perennial grasses would change fire behavior characteristics in areas currently dominated by Bromus tectorum. Frequency data were collected for both grazed and ungrazed seeded species and resident weed species. Moderate spring grazing did not negatively impact the establishment of seeded species at Camp Williams. Grazing at Promontory Point decreased Agropyron desertorum frequency and increased the frequency of Pascopyrum smithii. Biomass data collected for grazed and ungrazed treatments in both years indicated that moderate spring or winter grazing the first two years of establishment did …

Development Of New Aspen Cohorts: How Many Suckers Create An Adequate Condition And The Relationship With Ungulate Impacts?, Brian Ferguson, Dale Bartos, Wayne Shepperd

Aspen Bibliography

No abstract provided.

Executive Summary The Role Of Ungulate Herbivory And Management On Ecosystem Patterns And Processes: A Problem Analysis, John G. Kie, Martin Vavra

Aspen Bibliography

No abstract provided.

Long-Term Environmental Effects Of Conifer Removal To Achieve Aspen Release In Near-Stream Areas Within The Northern Sierras, Kenneth W. Tate, Bobette Jones, Melanie Mcfarland, Tom Rickman, Al Vasquez

Aspen Bibliography

The advanced state of conifer encroachment in aspen stands in the Sierra Nevada and southern Cascades is retarding aspen regeneration, putting an estimated 70 plus percent of stands at immediate risk of extinction with a significant percentage of stands already lost.