The minnow genus Siphateles is distributed throughout the Great Basin and adjacent drainages of western North America. Three species are currently recognized in the genus: S. alvordensis, Alvord chub, S. boraxobius, Borax Lake chub, and S. bicolor, the tui chub. S. bicolor has long been recognized as a widespread species...
This study evaluated the effects of tillage system, rotational tillage sequences, and winter seed burial depth on weed seedling recruitment in irrigated cropping systems. Notill (NT) planting of vegetable crops reduced emergence of hairy nightshade by 77 to 99% and Powell amaranth emergence from 50 to 87% compared to conventional...
Monitoring wildlife habitats has become important to forest ecosystem management because it provides valuable information about the response of forests and their species to harvest practices, impacts from recreational use, conservation efforts, and natural and human-caused disturbances. Monitoring is a complex task that requires a variety of abiotic and biotic...
Balancing resource extraction with protection of Pacific Northwest forest ecosystems requires understanding the population biology of ectomycorrhizal fungi. Design of landscape-scale management and research strategies requires understanding genet size, habitat requirements, and dispersal capabilities. The purpose of this dissertation was to gain knowledge about the distribution of genetic variation, systematics,...
Two North American subspecies of Snowy Plovers (Charadrius alexandrinus) have been described: the Cuban Snowy Plover (C. a. tenuirostris) and the Western Snowy Plover (C. a. nivosus). Coastal populations of the Western Snowy Plover are listed as Threatened under the U.S. Endangered Species Act, while populations of the Cuban Snowy...
Wild barley (Hordeum vulgare subsp. spontaneum) could be a source of useful genes for improving cultivated barley. The useful genes present in Hordeum vulgare subsp. spontaneum may be new alleles at described loci, or these may be entirely new genes in the sense that there is limited allelic variation at...
An experimental reintroduction was performed to determine the best method to create new populations of the tuberous species Perideridia erythrorhiza, a rare vascular plant endemic to southern Oregon. Only a handful of sites are currently present, and many of these are subject to other land uses such as urban development...