I conducted field studies to determine the effect of insect herbivory and
intraspecific plant competition on ragwort Senecio jacobaea. The objectives were to
determine the patterns and causes in the distribution of the ragwort flea beetle
Longitarsus jacobaeae foraging among varying densities of ragwort, to measure the
behavioral and numerical...
Most plant toxicology tests developed in support of environmental laws use a single stress applied to an individual plant. While tests using individual species or stresses require fewer resources and are easier to interpret, they are under increasing criticism for being unrealistic and missing important ecological interactions. The objective of...
Most of the presently grown cultivars of rice (Oryza sativa L.) have poor
competitive ability against weeds if compared with traditional cultivars. Therefore,
effective weed control is an important but often costly and difficult management
practice in rice crop production. If weed competitive ability of rice cultivars could be
improved...
Salmonberry (Rubus spectabilis) and thimbleberry
(Rubus parviflorus) are clonal shrub species common to
reforestation sites in the Oregon Coast Range. These
species have economic importance, because they reduce
conifer seedling growth and survival. A population modeling
approach was used to facilitate study of the biology of
these species and to...
Xylem is nonuniform in its structure and function throughout the plant stem. Xylem structure varies from pith to bark, from root to apical meristem, from stem to branch, at nodes vs internodes, and at junctions of branches, stems or roots compared to the internodal regions nearby. At smaller scales, anatomy...
Control oriented local area networks (COLANs) are being installed in factories at an increasing rate. Traditionally, process control has operated with a master scheduler (computer) monitoring a number of points in a control grid. As the complexity of today's process control needs grow, the need to process information locally increases....
This thesis presents a case study of applying machine learning tools to build a predictive
model of annual infestations of grasshoppers in Eastern Oregon. The purpose of the
study was two-fold. First, we wanted to develop a predictive model. Second, we wanted
to explore the capabilities of existing machine learning...
The purpose of this research was to develop methods for using geographic information system (GIS) analysis and unsupervised classification of Global Vegetation Index (GVI) images to improve carbon budget estimates of the former Soviet Union (FSU). A GIS was used to locate the geographic distribution and estimate the area of...