A study was performed to assess the uptake and retention patterns
of cesium-134 in the gray-tailed vole, Microtus canicaudus Miller. To
furnish a realistic source of contaminated food for the voles, wheat
seedlings were raised in hydroponic solutions to provide radiocesium
labeled wheat clippings. The hydroponic system was designed to...
Through its Policy Analysis section, the Forest Service has conducted a Long Term Training Program in Systematic Analysis (hereinafter called the Program) at Michigan State University, then later, jointly at both Michigan State and Oregon State University f or twenty years. Approximately one hundred graduates of the Program are r-ijW...
An investigation was conducted on factors influencing sex ratio in Eurytemora. Fifteen generations of brother/sister mating have produced family lines with a high proportion of either males or females of Eurytemora affinis. On this basis, a polygenic mechanism of sex
determination is proposed for E. affinis. Laboratory experiments on the...
Cheatgrass (Bromus tectorum L.) and yellow starthistle (Centaurea
soistitialis L.) have invaded over 3 million ha of grasslands in the western U.S.
Future management will require an understanding of the conditions,
mechanisms, and processes which control species dominance, community
dynamics, and desirable plant establishment in these alien dominated annual
rangelands....
The effect of nitrogen on influencing the competitive balance between a shrub, Artemisia tridentata ssp. wyolningensis (ARTRW) and a perennial grass Stipa
thurberiana (STTH) in a sagebrush steppe community was determined. Nitrogen levels were altered on 5x5 in plots by applying 4.5 gun2 of nitrogen in the form of ammonium...
The purpose of this study, to examine the relevance of U.S.
graduate education in agriculture to careers in agricultural
development of East African agriculturalists, was examined in
terms of three problems:
Problem 1: Was U.S. graduate education in agriculture
relevant to careers in agricultural development of East
African agriculturalists?
Problem...
The response to glyphosate [N-(phosphonomethyl) glycine] of two
dodder species Cuscuta campestris Yuncker (field dodder) and Cuscuta
indecora Chiosy (largeseed dodder) parasitizing alfalfa (Medicago
sativa L.) was compared. In the absence of glyphosate, alfalfa was
killed or severely injured by parasitism from uncontrolled dodder.
Results of field experiments in which...
The purpose of this study was to determine the concerns of past participants of the Summer Agriculture Institute regarding the use of agriculture as a context for teaching and to determine how they implement curriculum integration. The study used the Concerns-Based Adoption Model as a theoretical framework, which resulted in...
This qualitative study informed by a phenomenological approach explored the experiences of students when deciding to disclose bias-related incidents. Through an individual interview and follow-up focus group, eight participants shared their experience with bias-related incidents, decision to disclose or not to disclose, and perception of university resources. Five themes emerged...
Freeze/thaw cycles are numerous in agricultural soils of the Pacific Northwest. Potential loss of soil by erosion is high whenever a soil thaws from the surface creating a saturated soil overlying an impermeable frozen layer. Field studies were conducted to investigate the effect of surface residue on soil freezing. Residue...
Leaf elongation is a major indicator of plant growth. It is
controlled by complex interactions of many factors including light
intensity, photoperiod, water availability, atmospheric conditions,
and plant water stress. In this study, the response of leaf elongation
to length of photoperiod and to plant water stress as indicated by...
The effect of a static quadrupole interaction on the 133-482 Kev
gamma-gamma angular correlation in Ta-181 has been studied by the
delayed coincidence method. Using a source of Hf-181 in polycrystalline
hafnium metal, the anisotropy was measured as a function of
time between the formation and decay of the 482...
A number of investigators have proposed equations to predict
the permeability of porous media. Most of their equations are based
on the distributions of the sizes of the various contributing pores in
the medium. Presently the pore size distributions of agricultural
soils are most commonly obtained from soil water release...
The contemporary student veteran population is growing rapidly as service members who served in the Afghanistan and Iraq conflicts take advantage of the Post 9/11 Veteran Educational Assistance Act of 2008 to receive educational benefits to attend college (Cook & Kim, 2009). However, student veterans entering college today have a...
Atmospheric boundary layers become stably stratified at night over land when the surface becomes colder than the air layer above. In stable nocturnal boundary layers (SNBL), turbulence becomes weak and intermittent, terrain-induced phenomena such as drainage currents or gravity-waves emerge and the surface heterogeneity is enhanced. Because of their complexity...
The in planta growth of three wild type strains of phytopathogenic bacteria and three nonpathogenic mutant strains was studied to determine if mutations eliminating the ability of the mutant strains to cause disease had affected their growth in leaf tissue. The mutant strains were obtained by Tn5 mutagenesis of Pseudomonas...
Laboratory experiments were used to investigate the mechanism
of plant response to water stress by determining the sensitivity of leaf
elongation, photosynthesis and transpiration in young corn plants to a
decrease in leaf water potential.
In initial experiments, 9 day old corn plants were grown at soil
water potentials of...
At present the adsorption kinetic of ions by soil particles is considered to be a surface reaction. When the transport of solutes in soils is described using the one-dimensional flow equation, it becomes a serious problem that lateral diffusion of ions from the bulk solution towards the soil surfaces is...
Several large-scale marine heatwave events occurred during the last 10 years in the North Pacific. A particular extreme marine heatwave in the North Pacific called the blob created an unprecedented high peak of sea surface temperature (SST) during 2013/14. MHW events had significant impacts on downstream weather and precipitation patterns...
Over the last two decades, farmers markets have gained prominence based on their contributions to local economies, support of small-scale farmers, and ability to reconnect consumers and producers of food. Farmers markets vary substantially both in the goals they set and the outcomes they achieve. This study examines whether and...
Over the past twenty years, the national three-year graduation rate for community college students has ranged from 44% to roughly 31% in 2013 (NCES, 2013). As a way to address such low graduation rates, colleges have implemented a myriad of services and programs (i.e., tutoring, mentoring, etc.). Another intervention is...
This study investigates how teachers develop and extend their understanding and knowledge of teaching and learning with digital technologies in a primarily online Master of Science program. The investigation focuses on exploring the relationship between developing an online community of learners and the construction of technological pedagogical and content knowledge...
Douglas-fir seedlings were inoculated with different species of
ectomycorrhizae-forming fungi in order to test the concept that
ectomycorrhizae enhance the drought tolerance of seedlings and to
investigate the mechanisms responsible for this effect.
Seedlings were transplanted at age 6 to 8 weeks into pots
containing pasteurized loam soil and inoculated...
Oregon is one of several states to implement a new and innovative minimum wage policy. The Oregon policy defines three regions with each having a separate initial minimum wage and a different set of incremental increases over the next seven years. This paper explores how this policy change may impact...
The use of efficient basis functions to model and represent flows with
internal sharp velocity gradients, such as shocks or eddy microfronts, are
investigated. This is achieved by analysing artificial data, observed atmospheric
turbulence data and by the use of a Burgers' equation based spectral
model. The concept of an...
Community colleges today are experiencing monumental shifts in their operating
environments. Some of these changes are known, but many of them are not. They
include shifts in curriculum, funding, and societal expectation to name a few. Through
the constructs of high quality work environment and organizational fluidity theory, this
research...
In regions where soil temperatures limit plant growth, artificial
soil warming may be an economically feasible practice. This hypothesis
was evaluated in a soil warming experiment near Corvallis, Oregon.
This experiment was prompted by the observation that multiple
use of waste heat discharged in the condenser cooling water of thermal...
Post-secondary education institutions across the United States are increasingly allocating resources to promote international education exchange programs as a pedagogical praxis to develop students into global citizens. Underlying such notions of global citizenship is the assumption that students will also develop a stronger post-national or cosmopolitan identity as a result...
Noise induced hearing loss is a subject of growing
concern. Over the past 15 years, several well-documented
studies have been completed which express the relationships
between industrial noise exposure and damage to normal and
pathological ears. This research has provided knowledge of
considerable importance to developing successful hearing
conservation programs....
Farmers typically use three applications of glyphosate to control weeds in no-till fallow. Some are now experimenting with an unconventional modification to this widely used approach. This modified approach is based on an intentional delay in the time of the first spraying. Farmers delay their first spraying because they want...
Full Text:
for No-Till Fallow in the Driest Region of the
Inland Pacific Northwest
Larry K. Lutcher*
Farmers
Farmers typically use three applications of glyphosate to control weeds in no-till fallow. Some are now experimenting with an unconventional modification to this widely used approach. This modified approach is based on an intentional delay in the time of the first spraying. Farmers delay their first spraying because they want...
Full Text:
Larry K. Lutcher* 5
Farmers typically use three applications of glyphosate to control weeds in no
The physical properties of the purified cardiac muscarinic acetylcholine receptor have been examined by D₂O/H₂O sucrose gradient sedimentation and sephacryl S-300 gel filtration in Triton X-405 and dodecyl-β-maltoside. From the sedimentation experiments, the partial specific volume of the receptor-Triton X-405 complex were 0.813 cm³/g and 5.30 S, respectively and the...
This research was conducted on three study areas on elk winter
ranges in Northeast Oregon. One was on the Starkey Experimental
Forest and Range and the others were in the same vicinity. Plant
appendages, spring and fall defoliation and fall growth of bluebunch
wheatgrass were evaluated in terms of quality...
In 1976 and 1977 I examined three broad problems associated with the recruitment of young mallards, Anas platyrhynchos, in the Prairie Pothole Region of North Dakota. The three problems studied were: the effects of interspecific nest parasitism on production; the chronology and magnitude of total-brood loss during the brood-rearing period;...
Arthropod communities in pear are conceptualized as hierarchically
organized systems in which several levels of organization or subsystems
can be recognized between the species population level and the community
as a whole. An individual tree is taken to be the community habitat with
arthropod subcommunities developing on leaf, fruit and...
To learn more about the role β-galactosidase plays in rate of
acid production in milk by lactic acid bacteria, several lactobacilli
were examined for this enzyme. Cells from different species were
grown in lactose broth to induce β-galactosidase activity. The specific
activities of whole, solvent treated cells, and of cell-free...
Phytophthora lateralis Tucker and Milbrath, causal agent of a serious fungus root rot of Chamaecyparis lawsoniana, has seriously damaged natural stands in southwestern Oregon forests and affected ornamentals throughout the Pacific Northwest. Progress with an effective control program in the field has been limited by lack of critical knowledge of...
The surface wind and stress responses to sea surface temperature (SST) are examined using collocated moored buoy and satellite observations in the Gulf Stream and the eastern equatorial Pacific. Using 17 buoy pairs, differences in the wind speed, 10-m equivalent neutral wind speed (ENW), and surface wind stress magnitude between...
An analytic model for implementation of participatory process control was
designed from a literature review of management theory, organizational development,
statistical process control and base study methodology. A fieldwork research
plan was developed using case study methods to explain the functional flow of the
model. The research data on a...