Thesis submitted to the graduate faculty of Chadron State College in partial fulfillment of the requirements for the degree of Master of Arts in Education. / "October, 2008". Includes bibliographical references (p. 59-64). Also available in PDF via the World Wide Web.

Thesis (M.S.)--Oregon State University, 2008-01-15. / Printout. Includes bibliographical references (leaves 31-36). Also available on the World Wide Web.

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 95-100). Also available on the World Wide Web.

Graduation date: 2003

Thesis (M.S.)--University of Nevada, Reno, 2007. / "August, 2007." Includes bibliographical references. Online version available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 27-31). Also available on the World Wide Web.

Graduation date: 2004

Glasshouse and growth-chamber experiments were conducted to evaluate primisulfuron phytotoxicity and the influence of adjuvants on downy brome and Kentucky bluegrass. GR₅₀ (50% growth reduction) values were 0.97 ± 0.57 and 8.07 ± 1.85 g/ha for downy brome and Kentucky bluegrass, respectively. Primisulfuron was applied to downy brome and Kentucky bluegrass at 3 placement sites; foliar, soil, and foliar plus soil. Foliar or foliar plus soil applications were more effective at reducing downy brome dry weights than the soil application of primisulfuron, while Kentucky bluegrass was injured more from the soil or foliar plus soil applications than from the foliar application of primisulfuron. Primisulfuron at 5 g/ha applied alone reduced downy brome dry weights by 5%, whereas, when an adjuvant was added, dry weights were reduced by 52 to 83%. Primisulfuron was more phytotoxic to downy brome at alternating temperatures of 8-16 C and 16-24 C than at 0-8 C. Phytotoxicity of primisulfuron was less when downy brome plants were stressed for soil moisture after herbicide treatments than when the plants were not stressed or only stressed before treatment. / Graduation date: 1999

Thesis (Ph. D.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 123-135). Also available on the World Wide Web.

In the canyon grasslands of Garden Creek Ranch Preserve in Idaho, where the threatened plant Silene spaldingii occurs and invasion by the exotic species Centaurea solstitialis and Bromus tectorum is proceeding rapidly, I examined environmental and community patterns of site invasion, and evaluated the apparent influence of invasion on Silene population vigor. In addition, two separate lightning fires at the preserve presented the opportunity to examine the short-term influence of late-season fire on this species and its associated bunchgrass plant community. I found that Silene-supporting sites most often invaded by exotics were on relatively gentle slopes that received more incident radiation. This pattern may relate, in part, to light requirements of Centaurea solstitialis. Invaded sites were also typically at higher elevations, which may indicate they were moister and therefore more productive. The plant communities in invaded Silene-supporting sites were similar to plant communities in uninvaded sites, although invaded sites tended to have greater legume and exotic annual grass cover. Exotic species invasion did not appear to influence negatively the vigor of Silene populations, as indicated by similar plant height and comparable levels of flowering, fruit and seed set in invaded and uninvaded populations. The similarity in Silene vigor between invaded and uninvaded sites may reflect a moderating influence of site productivity in invaded populations, or may indicate that mature Silene plants and the exotic species partition space or resources differently, potentially reducing competition between them. However, Silene recruitment may be limited by competition from weeds; my data did not allow a rigorous test of this possibility. Fire apparently decreased cover of Festuca idahoensis and increased cover of Lupinus sericeus in the first year after burning, while cover of Pseudoroegneria spicata, exotic grasses, and most other forb species did not differ between burned and unburned areas. Silene cover and abundance within populations were similar before and after fire. Burning did not appear to influence levels of flowering, change the number of flowers or capsules produced per stem, or alter the number of seeds per capsule. Burning decreased plant size slightly, and decreased the proportion of flowers that matured to seed-filled capsules. Silene and the plant communities that support this species appear well suited to late season fire, however the response to burning in other seasons or at higher frequencies remains unknown in this study area. / Graduation date: 2003