Lamprey eel harvesting has systematically and periodically occurred along the Siletz River and its tributaries for as many as hundreds, or thousands, or tens of thousands of years that human families and lamprey eel populations have coexisted in the Siletz Valley ecosystem. Historical, cultural, and biological information for the twentieth...
Legislation to reduce the annual limit of field burning in Oregon has led to increased study of
alternative non-thermal grass-seed management methods. Of these methods, non-thermal residue
management, in combination with crop rotations and different tillage practices, offer potential to
equal or exceed crop production of conventional thermal production systems....
Seasonal reducing conditions play an important role in the cycling of nutrients and soil pore water chemical constituents in the Willamette Valley. Long periods of soil saturation lead microorganisms utilizing organic matter as their carbon source to find alternative electron acceptors other than oxygen. Once oxygen has been depleted microorganisms...
Rapid and accurate analytical methods are needed to assess the impacts of agricultural chemicals on soil and water resources. Solid-phase extraction (SPE) was evaluated as an alternative method to conventional liquid-liquid extraction for the quantitative analysis of the herbicide DCPA and its metabolites in ground waters. Strong anion exchange (SAX)...
Much interest has recently been shown in using fecal samples to monitor
hormone concentrations in free-roaming animal populations. This process is noninvasive
and, therefore, provides easy sample collection and assures no stress-related,
physiological responses that might alter the hormonal data. Concerns have been
expressed, however, that the hormone concentrations detected...
Pole-sized, live western larch Larix occidentalis Nutt.) were inoculated with Ophiostoma pseudotsugae(Rumb.) von Arx or Leptographium abietinum (Peck) Wingf., two blue stain fungi associated with the Douglas-fir beetle (Dendroctonous pseudotsugae Hopkins), to assess their pathogenicity. Inoculation with O. pseudotsugae resulted in a significantly greater percentage of necrotic phloem compared to...
Surfactants, or surface active agents, are the active ingredients in detergents used for
domestic cleaning applications, such as dish washing and laundering. They are effective cleaning
agents by concentrating at interfacial regions, lowering the surface tension of water, and forming
micelles that solubilize oils (West, 1992). Surfactants are amphiphilic, because...
Leaves of healthy strawberry plants were inoculated with either vinclozolin-sensitive or vinclozolin-resistant isolates of Botrytis cinerea at one of three concentrations: 5x104, 1x105, and 5x105 conidia/ml. One week following inoculation, representative leaves were harvested and cut into 9mm2 leaf pieces. Some pieces were immediately plated onto selective Botrytis medium while...
Using a spectrometer and photomultiplier tube, I measured the electromagnetic radiation transmittance properties of three types of tissue-- ventral skin, cardiac muscle, and liver tissue--in the red-sided garter snake Thamnophis sirtalis parietalis between the wavelengths of 450 and 850 nanometers (nm). Control readings were taken using a 10⁻² neutral density...
Evaporative loss rates of pesticides, following application to turfgrass, were measured using the Backward-Time Lagrangian stochastic Dispersion model (Flesch, Wilson, Journal of Applied Meteorology, 34, pp. 1320-1332. All pesticides were applied to a 22.8 m x 22.8 m orchard ryegrass turf plot near Corvallis, Oregon. Solar radiation, ambient temperature, surface...
Polycyclic aromatic hydrocarbons (PAHs) are a class of usually planar
compounds consisting of fused aromatic rings that are formed by the incomplete
combustion of organic materials. PAHs are ubiquitous in the environment, coming from
a number of sources, such as cigarette smoke, the burning of wood for residential heating,
and...
Ontogenetic niche shifts are critical times in a fish's life that need to be passed for
survival, growth and recruitment (Gerking 1994, Osenberg et al. 1994). These niche
shifts are identified by a change in feeding from one prey type to another. These shifts in
feeding occur throughout growth and...
The development of winter 6-row malting barley varieties is an objective of the OSU program. The program's winter germplasm is quite susceptible to Barley Yellow Dwarf Virus (BYDV). The program recently released the spring 2-row variety Orca, which carries the Yd2 gene for BYDV resistance. The objective of this project...
Needle length in young ponderosa pine (Pinus ponderosa Dougl. ex Laws var. ponderosa) was assessed for its ability to estimate site quality of afforested land in Neuquén, Argentina. The objective was to determine the best aspect on the tree, number of needle age classes, and number of trees that would...
This report examines the feasibility of using the bivalve Corbicula flumina as a biomarker for environmental contaminants in the Willamette River. Compounds such as DDT, dioxins, furans, and PCBs persist in the environment, pose health related concerns, and due to their lipophilic nature accumulate in biological organisms. The success of...
This study examined the management situation for the Columbiaroot-knot nematode (Meloidogyne chitwoodi) in potato, using an approach with systems thinking and interactive meetings. The focus of current research for control of this nematode was evaluated. Control practices include crop rotation, and this study also evaluated popcorn cultivars for their potential...
An important by-product of the kraft pulping process, black liquor is currently used in most pulp mills to produce steam in a recovery boiler. Two important black liquor characteristics are viscosity and burning (firing) characteristics, which determine the operating efficiency of the recovery boiler. Kraft black liquor is a complicated...
Nitrosomonas europaea is an autotrophic ammonia-oxidizer that has been found to cometabolize various halogenated hydrocarbons. This ability to cometabolize various compounds (many of which are considered contaminants) has caused N. europaea to be considered a potential bioremediational organism. However, ifN. europaea is to be used for bioremediation purposes, it will...
A broad range of factors influence wine grape quality and manipulation of these factors has stimulated interest among grape growers, wine makers, and research scientists alike. One such factor affecting wine grape quality is crop level, particularly for Pinot noir. Since the capacity of a vine to ripen fruit depends...