Yellow nutsedge is an important weed problem in the furrow irrigated fields in the Treasure Valley of eastern Oregon and southwestern Idaho. Field studies were conducted in 2008 and 2009 to evaluate the effect of PPI S-metolachlor or EPTC followed by POST halosulfuron and dicamba plus glyphosate or glyphosate alone...
Greenhouse studies were conducted to evaluate the influence of selected adjuvants on
glyphosate efficacy on yellow nutsedge and tuber production. Glyphosate was applied
at 0, 0.25, 0.43, 0.87, 1.26 (1x rate), and 1.74 kg ae ha⁻¹ 31 d after yellow nutsedge
was planted. Each rate was mixed with one of...
Responses of biological indicators of soil quality to winter cover cropping were measured on soil samples collected from 6 commercial growers' fields and two experiment research stations in the Willamette Valley of Oregon. The research stations were the North Willamette Research and Extension Center (Aurora, OR), and the Oregon State...
Calls for increased farmer involvement in research and extension programs
have been numerous and well supported. One approach to integrate the collective
knowledge and experience of agricultural scientists and farmers is through whole
farm case studies (WFCS). An interdisciplinary team of 34 research and extension
personnel at Oregon and Washington...
Concerns have been expressed that wheat (Triticum aestivum L.) cultivars selected under optimum conditions may lack adequate adaptation for stress environments. Experimental populations were grown under three environmental conditions 1) optimum, 2) reduced irrigation, and 3) high temperature. Field experiments were conducted at the Center for Northwest Experimental Station (CIANO),...
Wheat is a staple food crop with many applications. The composition and quantity of major and minor flour components greatly influence functional dough properties, processing quality, and end-use suitability. Seven to 15% of the weight of wheat flour is protein and the gluten proteins comprise 80-85% of that. The gluten...
Giant reed (Arundo donax L.) is a candidate to provide feedstock for the Portland General Electric power plant in Boardman, Oregon. Giant reed is a fast perennial grass, producing 23-27 metric tons ha⁻¹ of biomass and has the ability to adapt to diverse environments making it a good candidate for...
Field studies were conducted in 1998 and 1999, to evaluate glyphosate and glufosinate for control of redroot pigweed, common lambsquarters, hairy nightshade, and barnyardgrass in herbicide-resistant sugarbeets. Treatments that included two or three applications of glyphosate, regardless of rate, or glyphosate applied once in combination with BAS 656 07 H...
Both red (Trifolium pratense L.) and white (Trifolium repens L.) clover
seed yields can be highly variable and low in western Oregon. The objectives of
this study were to: i) determine crop water requirements and supplemental
irrigation timing, and ii) quantify the effects of soil and water status on
inflorescence...
There is no information available on water management of birdsfoot
trefoil grown for seed. Information is also not available describing how to
minimize seed losses due to shattering in order to obtain consistently high
birdsfoot trefoil seed yields. The objectives of this research are to: (i) quantify
crop water use,...
Sandy soils are among the least productive soils because of their inability to
store adequate water for plant growth. Their high percolation rate not only allows
water to move quickly beyond the root zone, but also washes nutrients below the reach
of plant roots. High evaporation occurs from the soil...
Oregon State University researchers are expanding their study of mineral nutrition in winegrapes as part of a project sponsored by the Wine Advisory Board. Further research is justified because of increasing grower interest in nutritional factors that affect production and quality. Winegrape growers utilize Oregon State University's Plant Analysis Laboratory...
Jointed goatgrass (Aegilops cylindrica Host) infestations in winter wheat (Triticum aestivum L.) production regions of the central and western USA result in severe economic losses in the wheat market. Field and greenhouse studies were conducted to determine the vernalization requirements of winter wheat, spring wheat, jointed goatgrass, and wheat by...
Vernalization plays a fundamental role in the adaptation of winter cereals to their growing environment by controlling their growth habit, thereby allowing them to escape cold injury. Because of the climatic conditions of the region, dry summers and wet winters, growers sometimes cannot plant all of their winter wheat in...
The objective of this study was to examine the variation among ammonia-oxidizing and denitrifying communities in soils of a natural Fennoscandian boreal forest and of a forest with a long history of fertilization with different levels of nitrogen (N), and to examine whether there are any changes in the microbial...
Algae can be used in a variety of wastewater systems to capture nutrients while fixing carbon dioxide from the atmosphere. I conducted field trials at three locations in Oregon with both corn and potato crops to assess the agronomic value and environmental impact of using the resulting algal biomass as...
A GIS analysis procedure was developed to explore relationships between imagery, yield data, soil information, and other assessments of a field or orchard. A set of conversion utilities, a spreadsheet, and an inexpensive shape file viewer were used to manipulate, plot, and display data. Specific features described include procedures used...
Cultivars of several cereal crops have been developed with acetohydroxyacid synthase (AHAS)
insensitivity to imidazolinone herbicides and are now an important tool for weed management.
Options for screening for imidazolinone resistant lines include direct herbicide application,
biochemical assays for AHAS activity and DNA-based methods. Herbicide and biochemical
assays for AHAS...
Soil surveys provide essential information for making land use and management decisions on publicly-owned lands in the semi-arid Great Basin. Soil maps produced with conventional mapping techniques are time-consuming, costly, and do not explicitly document the soil scientist's mental soil-landscape model. Predictive soils mapping using decision tree analysis (DTA) can...
Ammonia (NH₃)-oxidizing bacteria (AOB) and thaumarchaea (AOA) co-occupy most soils, yet no short-term growth-independent method exists to determine their relative contributions to nitrification in situ. Microbial monooxygenases differ in their vulnerability to inactivation by aliphatic n-alkynes, and we found that NH₃ oxidation by the marine thaumarchaeon Nitrosopumilus maritimus was unaffected...
Oregon is the world’s leading producer of crimson clover (Trifolium incarnatum L.) seed. Recent research has reported that seed yield has been increased in cool-season grass and red clover (T. pratense L.) seed crops with the application of trinexapac-ethyl, a gibberellic acid biosynthesis inhibiting plant growth regulator (PGR) and lodging-control...
Open-field burning has been an effective, economical, and widespread method of post-harvest residue management in creeping red fescue seed production in the Willamette Valley since the late 1940s. However, the use of field burning has been legislatively restricted due to air quality and safety issues. The foliar-applied plant growth regulator...
Published 1975. Revised February 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Industrial emissions of SO₂ and NOₓ, resulting in the formation and deposition of sulfuric and nitric acids, affect the health of both terrestrial and aquatic ecosystems. Since the mid-late 20th century, legislation to control acid rain precursors in both Europe and the US has led to significant declines in both...
This study investigates the use of predictive mapping techniques as well as geotechnical criteria in developing a multiregional soil liquefaction model and subsequent maps. The maps were produced using National Cooperative Soil Survey data, in the gSSURGO format, combined with soil liquefaction data gathered from studies, articles, and traditional seismic...
My research has focused on understanding N and C cycling in soils at small scales. Isotope dilution methods commonly used to estimate gross rates of soil chemical transformations assume homogeneous distribution of label. I explored the effects of diffusion limitations on isotope dilution experiments in soil aggregates using spherical diffusion-reaction...
This manual is designed to serve as a resource for those who organize and conduct training programs in biosolids management. It describes the process of organizing and conducting effective training sessions as well as the technical topics that should be covered.
Seed shattering is a constraint to improvement of seed yield in Lolium perenne L. and as a result, seed retention is an essential trait for this valuable crop. Field studies were conducted near Corvallis, OR in two years (2017-2018 and 2018-2019) to identify genetic variation for seed retention and to...
Transitional areas between upland and aquatic habitats, commonly known as
wetland, were once viewed as unproductive areas and were drained for farming or
pasture. Wetlands are now accepted as significant ecological resources, and their
protection is a mandate of federal, state, and local land managers. Due to the
diversity of...
Improving quality of hard white wheat (HW) cultivars in the Pacific Northwest is important to expand exports to Asia. Asian food processors prefer HW grain that can satisfy an array of baking needs, as well as produce superior quality noodle products. Three experimental populations were developed from single cross and...
The objectives of this thesis were to examine the links between soil microbial community composition and function using the nitrogen (N) cycle as a model for these interactions and to assess the impact of environmental factors such as microclimate, vegetation type, and nutrient availability on microbial diversity and N transformations...
Arctic warming is exposing thawing permafrost to repeated freeze-thaw, a disruptive process that can alter soil biogeochemistry and physical structure. To investigate the impact of permafrost exposure to freeze-thaw, soil response was tested across three scales: 2.5 cm³ aggregates, a forested hillslope, and two sites at contrasting latitudes. XCT imaging...
The use of DNA markers in public sector plant breeding is now the norm. Such markers are common across breeding programs and this commonality enables and enhances collaboration. Therefore, large collaborative research projects that measure several phenotypes across multiple environments coupled with the expanding amount of genotype data attainable with...
Fall-planted barley makes the best use of available precipitation in the Pacific Northwest of the United States. This growth habit is also suitable to many other areas of the world. A prerequisite for production in most of these areas is tolerance of low temperature during the vegetative growth stages. Fall-planted...
Frankia from root nodules of nine different species of Ceanothus were
characterized. DNA was amplified directly from nodular material using the polymerase
chain reaction (PCR). The amplified region includes the 3' end of the 16S rRNA gene,
the intergenic spacer (IGS), and a large portion of the 23S rRNA gene....
The hop (Humulus lupulus L.) is a dioecious, diploid (2n=2x=20) species. Triploid
hops (2n=3x=30) are easily obtained from tetraploid by diploid crosses and are preferred
because of their natural seedlessness and increased vigor. The female inflorescence is used
for flavoring beer. Because brewers require product consistency, the brewing characteristics
of...
Excessive growth by red clover, Trifolium pratense L., grown for seed
interferes with maximum seed production and harvest in Oregon's Willamette Valley.
This study was conducted during 1986 and 1987 on red clover cv. Kenland to
determine if plant height and dry matter production could be inhibited and seed yields...