Esophageal fistulation, stomach content analysis, fecal analysis,
and ocular-estimate-by-plot are four of the most publicized methods
of determining the diets of large herbivores. The principal objective
of this study was to compare the relative values of each of these
methods based upon information collected from bi-fistulated (esophageal
and rumen) sheep...
An experiment was conducted to evaluate the influence of forest fuels reduction on the diet quality, botanical composition, relative preference, and foraging efficiency of beef cattle grazing at different stocking rates. A split plot factorial design was used, with the whole plots (3 ha) being fuel reduced or no treatment...
Managing cattle to disseminate seeds of desirable plants, or alternatively, to restrict weed seed contamination on rangelands is of interest to managers. Four experiments were conducted to determine effects of ruminant digestion on germination of ingested seeds. A number of plant species representing a variety of seed size and seed...
Yellow starthistle (Centaurea solstitialis L.) is an introduced Asteraceae that has become established on 10 million acres in the Pacific Northwest and California. This weed functions as an annual or short-lived perennial and depends on seeds for reproduction. Strategies of control that reduce plant fitness or lower seed production or...
Properly functioning riparian systems are vital to the health of watersheds and provide an important forage and habitat resource for livestock and wildlife. Riparian grazing management strategies that are economically feasible and achieve environmental goals are needed by resource managers and livestock producers. The objective of this thesis was to...
Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ecosystems, however, these biodiversity hotspots are increasingly under threat of exotic plant invasion. Evaluation of plant species distribution patterns in mountain...
Spring chinook salmon spawning occurs in late summer when it is common for cattle to be present in pastures that have streams where fish spawning occurs. This two-year study addressed three main objectives relative to behavioral interactions between cattle and spring chinook salmon during the spawning life history stage. These...
Field trips are well recognized by researchers as an educational approach with the potential to complement and enhance classroom science teaching by exposing students to unique activities, resources, and content in informal settings. The following investigation addresses teachers' field trip practices in three related manuscripts:
(1) A study examining the...
Nutritional ecology of unhunted and sympatric populations of
Roosevelt elk, Cervus elaphus roosevelti, and Columbian black-tailed
deer, Odocoileus hemionus columbianus, was investigated in old-growth
forests of the Hoh Valley in Olympic National Park, Washington, from
September 1979 to November 1981. Seasonal diets of both cervids
generally were comprised of common...
This exploratory study posited that being in an insecure marriage would increase marital conflict and perceived relational aggression when the couple is experiencing economic constraints. The cross-sectional design assessed two groups of marriages: secure and insecure. A structural equation model using multiple group comparison tested the effect of each type...