Red clover (Trifolium pratense L.) seed yield can be affected by plant growth regulators (PGR) and irrigation; however, the effects of these factors on physiological maturity (PM), harvest maturity (HM), and seed quality are unknown. The objectives of this study were to: 1) determine how irrigation and trinexapac-ethyl (TE, a...
In the midst of double-digit growth in market demand for organic products, there is a lag in the growth of certified organic production in the United States. This thesis investigated the motivations and barriers farmers face when making the transition to organic agriculture. Three distinct organic farmer typologies were identified:...
Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, greater irrigation efficiency must be achieved while simultaneously maintaining or increasing crop yields and farming profitability. Incremental water use decisions are made...
Rivers impacted by human activities often have multiple stressors present. The effects of multiple stressors on biological communities can often be difficult to predict, due to the potential for complex interactions between stressors and communities. This thesis explores the impacts of two stressors often associated with agricultural land use, increased...
Stevia (Stevia rebaudiana) is a perennial herbaceous plant native to Paraguay and used traditionally by the native Guarani peoples for centuries to sweeten medicinal teas. Stevia has only been commercially cultivated over the past 50 years and cultural practice information suitable for implementation by growers is limited. Currently stevia’s commercial...
There is limited information available on production of trailing blackberry, particularly certified organic plantings, which are of interest to growers as there is increased consumer demand and a price premium over conventionally-produced fruit. Various production strategies were evaluated for their effect on yield, biomass production, carbon (C), and nutrient concentrations...
Reservoir systems in the western US are managed to serve two main competing purposes: to reduce flooding during the winter and spring, and to provide water supply for multiple uses during the summer. Because the storage capacity of a reservoir cannot be used for both flood damage reduction and water...
The purpose of this study was to make a preliminary
investigation of the productivity of some of the soils
within the Willamette catena under different systems of
soil management. The study was carried out at four experimental
sites near Corvallis, Oregon, during the 1962 growing
season. The soil at each...
Some consideration has been given to the irrigation of winter
wheat in the Willamette Valley of Oregon. This important crop has
yielded quite well since the development and introduction of the
stiff-strawed, semi-dwarf wheats, but, because of the usually dry
early summers, it has been suggested that irrigation of winter...