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...