This dissertation describes arthropod responses to and effects on decay processes in ponderosa pine, a dominant forest canopy tree in northern California. We used both descriptive and experimental field techniques to establish how arthropod assemblages depend on and are important to the disintegration of woody structures in forests of this...
Ponderosa pine is an important species both commercially and ecologically in western North America. This study considers the incidence of insect and disease pests on a series of replicated ponderosa pine research plantations in northern California. The studies, on an environmental gradient, contain a series of silvicultural treatments including vegetation...
The pine butterfly (Neophasia menapia C. Felder & R. Felder) (Lepidoptera: Pieridae) is a relatively host-specific defoliator of ponderosa pine (Pinus ponderosa Dougl. ex Laws). From 2008 to 2012, the Malheur National Forest was subject to an outbreak of pine butterfly in ponderosa pine, peaking at ~100,000 ha of forest...
Whitebark pine (Pinus albicaulis) is an iconic North American high-elevation tree species currently threatened by climate change, mountain pine beetle, and white pine blister rust (WPBR), a lethal disease caused by the non-native fungal pathogen Cronartium ribicola. In collaboration with the USDA Forest Service Dorena Genetic Resource Center, germplasm was...
Western white pine historically dominated northern Idaho’s forested landscape and was the Inland Empire’s most economically important tree. White pine blister rust, caused by the exotic fungus Cronartium ribicola, played a principal role in the decline of western white pine. The pathogen causes branch and bole cankers, which usually girdle...
Cultural practices in snap bean production were evaluated at the Oregon State University Vegetable Research Farm Corvallis, Oregon. In addition, decision-making in snap bean production was assessed on five farms in the Coburg-Junction City-Harrisburg regions of the Willamette Valley, Oregon. A field experiment with cover crop and tillage techniques was...
The objective of this dissertation is to introduce low-cost processing methods for the fabrication of ZnO transparent thin-film transistors (TTFTs). A novel method for depositing ZnO body layers via spin-coating of a zinc nitrate-based spin solution is presented. The processing conditions of spin-coated ZnO are optimized to produce continuous and...
The goal of this project was to develop an integrated pest management strategy
for the control of a powder-post beetle (Dinoderus minutus F.). This species causes
serious damage in Philippine bamboo. Developmental threshold and thermal constants
were examined and natural enemies and ftmgi associated with beetles were investigated.
Finally, the...
Several plant hormones, including ethylene and jasmonates, are known to mediate responses against biotic and abiotic stress. The first and second objectives of this thesis were (i) to elucidate the role of ethylene in defense responses against Botrytis cinerea and specifically (ii) to determine the potential contribution of ethylene response...
Hypersensitive response-like (HR-like) needle reactions to infection by the white pine blister rust pathogen, Cronartium ribicola, have been reported for several species of five needle pines native to western North America. The best-studied examples are in Pinus monticola and P. lambertiana. In these species a "needle spot" phenotype has been...