Seed yield in ryegrass (Lolium spp.) is the
product of the number of fertile tillers per unit area
and seed weight per spike at maturity. These
components of yield develop through a series of growth
stages beginning with tiller bud initiation and
finishing with seed filling. Environmental conditions
during plant...
This study was undertaken to obtain information on the quality of grass seed when windrowed at the high moisture levels necessary for obtaining maximum yields. A secondary goal was to monitor moisture and temperature fluctuations in the windrow and to relate their effects to development and deterioration of the seed....
Orchardgrass and tall fescue seed crops are commonly springplanted
in Oregon, but do not produce a marketable crop during the first
growing season. Establishing orchardgrass and tall fescue with cereal
companion crops would provide income during the seeding year and could
increase seed production profits. This study was conducted to...
Increases in wheat production due to breeding may be reaching
a plateau. The application of N-fertilizer beyond optimum levels
leads to lodging and to an increase in tiller death. The use of
plant growth regulators (retardants) may be an answer for future
increases in production.
Experiments were conducted in 1983...
Vegetation as a soil-forming factor was studied under forest
transition and grass while attempting to keep other soil forming factors
constant in the western part of the Willamette Valley, Oregon. The
physiographic units consist chiefly of the interior foothills and slopes
formed from an old basaltic flow with some interspersed...
Forest associations, secondary succession, and relationships
of plant communities to Roosevelt elk were investigated. Stratification
of vegetation into ecological units and an understanding of secondary
succession by habitat-type were a necessary first step in investigations
into browsing of conifers by elk. The study was jointly conducted
by the Oregon State...
The study was conducted over approximately 191,000 acres in central Klamath County, Oregon. The research had three objectives: first, to describe and classify the seral and near-climax vegetation by using polyclimax principles; secondly, to determine the southern extension of five plant associations and one plant associes as previously described by...
As the management of range lands is intensified or as improvement
activity is increased, a critical need is seen to refine the
understanding of the ecology of these lands. If soil surveys on range
lands are to be meaningful and useful, the relationship between the
fundamental ecological units and the...
A study was initiated in 1961 to characterize seral plant
communities in a part of the Cedar Creek drainage in the Tillamook
Burn. Stratification of vegetation into ecological units was a necessary
first step in conifer-animal damage studies supported by the
Oregon State Game Commission.
Reconnaissance information was recorded in...
The response of Canada milkvetch (Astragalus canadensis var. mortonii) to range and forest improvement practices was studied on a stand of mixed-coniferous forest which was clear -cut and burned in 1963 and 1964, respectively. The field studies were conducted on the Hall Ranch of the Eastern Oregon Experiment Station during...
The research presented in this thesis evaluated the effects of
uranyl (UO₂⁺⁺) upon the absorption of Li, Na, K, Rb, and Cl. Due
to the biological importance of Na and K, these two ions were
studied in the greatest detail.
The results of this research showed that, at UO₂⁺⁺ concentrations...
Field study with 5 tall fescue genotypes treated at the vegetative
growth stage, with 0, 0.28, 0.56, and 0.84 kg/ha of mefluidide
was initiated in July, 1980. The regrowth of these plants were again
treated at the booting growth stage in April, 1981, with the same
rates of mefluidide as...
Studies were conducted from 1962 to 1966 to investigate the
effectiveness of several practices in manipulating medusahead
(Taeniatherum asperum (Sim. ) Nevski) infested and/or dominated
ecosystems by releasing competition in favor of perennial grasses.
Several herbicide treatments were evaluated for selective
control of medusahead and cheatgrass (Bromus tectorum L. )...
Land useable for livestock grazing in the western United States is
diminishing because of spreading municipalities, irrigation developments,
highway construction, recreational demands and withdrawals.
Concurrently, the demand for livestock and livestock products is increasing
because of a rapidly growing population. As a result, production
from the grazing land that remains...
Relationships between soil-water stress and plant-moisture
stress were studied with respect to soil classification and cambial
activity in Douglas-fir.
The study sites were forested with Douglas-fir and located in
McDonald Forest and near Marys Peak in the Oregon Coast Range.
Soil-water depletion was followed by the use of gypsum blocks...
Making quality and winterhardiness in barley are "ultimate" phenotypes composed of
component, quantitatively inherited traits. A 69-point genome map of the seven chromosomes of
barley was used, in conjunction with multi-environment phenotypes for grain yield and malting
quality, to determine the chromosome locations of quantitative trait loci (QTLs). A combined...
Three Nelder plots of 3-year-old red alder (Alnus rubra Bong) were used for this study at the Cascade Head Experimental Forest, Oregon in the growing season of 1988 at an elevation of 330 meters. Each Nelder plot
represented a range of densities from 238 to 101,219 trees per hectare. The...
The objectives of this study were (a) to measure the amount
of cross-pollination caused by three bee species at 10, 20 and 40
rods distance from a foreign pollen source, (b) to measure the effects
of bee species, planting pattern and season on broad sense heritability
estimates for seed yield...
Tall fescue often results in poor liveweight gains. This may be accounted for by variations in perloline content, nitrogen content, or digestibility of the plant. Two groups of tall fescue plants were examined for each of these traits. These groups consisted of (a) fifteen single-crosses of a six parent diallel...
An evaluation of fabric reinforcement of the roadway
structure is made. The study includes a parametric analy
sis using layered elastic theory and a series of large
scale model tests.
The parametric. study analyzes the stresses and
strains of roadway structures with a fabric layer between
tna surface layer and...
The primary goal of this research was to determine the concentration and composition of nucleotides, as nucleoside monophosphates and nucleobases, in the underutilized reproductive organs (milt and roe) of Alaska pollock (Gadus chalcogrammus) and yellowfin sole (Limanda aspera). Changes in concentrations of these nucleotides and nucleotide analogs were observed with...
A study was conducted on German velvetgrass (Holcus mollis L.), a weedy, rhizomateous perennial grass introduced in the
United States in relatively recent years, The purpose of this study
was to learn more about its distribution, growth habits, and control
under conditions found in Western Oregon. German velvetgrass infestations of...
Studies were conducted to determine the nature of the interaction
between atrazine (2-chloro-4-ethylamino-6-isopropylaminos-
triazine) and magnesium on tomatoes. This interaction was
studied under two light regimes: continuous light and a 12-hour
photoperiod. Tomato plants were grown in sand cultures at three
levels of magnesium fertilization. Four weeks after planting,
atrazine...
Investigations were conducted to (1) determine the original
pattern of deposition and thickness of ash in the Ochoco and Blue
Mountain areas of Oregon, (2) determine if discontinuities exist in
the parent material of these soils, (3) determine the degree of mixing
of ash with other materials and evaluate reworking...
Two cultivars of tall fescue (Festuca arundinacea
Schreb.) with contrasting growth habits were studied under
field and growth chamber conditions. Fawn, an established
cultivar since 1964, and TFM, an experimental line, were
observed to grow better during spring and fall months
respectively, in the field. Different temperature regimes
of 10/4,...
Procedures were developed for assaying the biosynthesis of (-)-
kaurene-¹⁴C and other intermediates in gibberellin (GA) synthesis
from mevalonic acid-¹⁴C in cell-free enzyme extracts of immature
pea (Pisum sativum L. cv. Alaska) seeds. This system was utilized
to investigate three aspects of GA biosynthesis: (1) apparent capacities
for (-)-kaurene biosynthesis...
A numerical model, simulating the complex behavior of reinforced soil walls using the finite element method, was developed to evaluate the behavior of a surcharged, geosynthetic-reinforced retaining wall with modular block facing. A nonlinear elastic-plastic constitutive soil material model was calibrated to experimental plane strain test data, while the performance...
A sequence of soil profiles was sampled along a climate-vegetation transect on the dated Mazama pumice fall in central
Oregon. The <2 μ size fraction from each sample was characterized
with respect to the relative significance of amorphous and
crystalline components, and the individual minerals of the latter
group were...
Pre-Tertiary metamorphic rocks, Jurassic granitic intrusions,
and Eocene basalts are exposed along the North Fork of the John Day
River at its confluence with Granite Creek. Geochemical and textural
evidence suggest greenschist-metamorphosed, strongly sheared,
volcanogenic rocks originated in an island-arc environment. These
greenstones were apparently intruded during the Late Permian...
Bacterial contamination is one of the most important problems
both in plant tissue culture research and commercial laboratories. Early
detection of contaminants saves time, effort, and money. Strawberry
runner explants were screened for contaminants during June to August,
1994 and 1995. Most contaminants found were bacterial rather than
fungal. Bacterial...
Total copper concentrations of 10 [mu]g/l to 100 [mu]g/l appeared to
alter the predator-prey interactions of fathead minnows (Pimephales
promelas) and Daphnia pulex. The effect of copper concentration on
the total amounts of D. pulex consumed over a 12-h period varied with
the density of prey stocked hourly in the...
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...
A three-year investigation was conducted during 1980-1982 to
evaluate the potential of using herded sheep as a silvicultural tool
to suppress brush in Douglas-fir (Pseudotsuga menziesii) plantations
of Oregon's Coast Range. Sheep browsing of Douglas-fir was highest
in May soon after bud break. Averaged over the 2 years of grazing,...
Two methods of separating sugars and acids of Bartlett pears
were compared to decide upon a working method for later studies
involving identification and quantitation of sugars and acids during
ripening of pears and in the production and storage of pear concentrate.
The first method involved precipitation of acids with...
The Northern Rubber Boa (Charina bottae) is a small, secretive boa native to the Pacific Northwest. Despite this being possibly the highest latitude boas and one of only two boas native to the continental U.S., it has received surprisingly little attention. Most of the research on the natural history of...
The ringtail (Bassariscus astutus) is a small, nocturnal, meso-carnivore that occupies mid-elevation forests in the southwest portion of Oregon. Ringtail are fully protected within Oregon, but a species of conservation concern as they may be vulnerable to habitat loss and fragmentation. Limited data exists regarding ringtail ecology in forested ecosystems,...
Columbian black-tailed deer (Odocoileus hemionus columbianus) are important economically, ecologically, and culturally as an indigenous species in western Oregon. Oregon Department of Fish and Wildlife (ODFW) observed declines in black-tailed deer populations since the late 1980’s and attributes these declines to reduction in quality and availability of habitat, following the...
Inkjet printing offers a cost effective, highly customizable method for rapid manufacturing of functional devices with minimal material waste. Although this method has been used for a variety of composites, little work has been done in the area of 3D printing magnetic composites. Presented here is a process for inkjet...
Bulk metallic glasses (BMGs) are relatively new amorphous materials that have received much attention in recent years. Rapid cooling methods from the liquid state provides the possibility to bypass crystallization during solidification. Due to the lack of crystal defects such as grain boundaries and dislocations, BMGs can have some special...
The rate of the C¹⁴0₂ release from glucose, specifically labeled
with C¹⁴ at 1, 2, 3+4, and positions, was used to study the relative
participation of pathways of glucose catabolism in red beet slices.
Evidence was obtained which indicated that in mature red beets glucose
was catabolized mainly via glycolysis-tricarboxylic...
One of many important physical properties that must be known
to understand transport phenomena in soils is pore size distribution.
Presently the pore size distributions of soils are most commonly
obtained from soil water characteristic curves. The soil water characteristic
curves are usually obtained by the pressure plate technique.
It...
Independent fission product yields are primary input nuclear
data in the evaluation of nuclear reactor after-heat when using a
nuclide-decay summation method. The error in yield values is one
of the major causes of uncertainty of this calculation. Since only
a small fraction of the fission product yields has been...
Sulfur-coated urea (SCU), a slow release nitrogen fertilizer,
may be economically competitive with conventional fertilizers, but
little is known of the mechanism of urea release from SCU and the
environmental factors which affect the urea release rate. Objectives
of this thesis were: (1) to determine factors which affect the rate...
Bitterbrush [Purshia tridentata (Pursh) DC] plants were burned or
clipped, fall and spring, under different soil moisture conditions on
two sites in east-central Oregon. Treatments, on plants of an erect
growth form on the Juniperus/Artemisia-Purshia site resulted in 38% of
the fall-clipped and 40% of the spring-clipped plants sprouting. None...
The objective of this study was to determine interrelationships among agronomic traits in early and late maturing populations. Two populations were obtained from the crosses, Roussalka/Tesopaco 76 and Yamhill/Aspen. Seeds were space planted with split plot design and nine agronomic traits were observed. In comparative studies between early and late...
The black grass bug genus Irbisia Reuter was revised. Over 18,000
specimens were examined and information concerning the biology, host
plant and distributional relationships of the species was compiled.
In addition to external characters, the male claspers and vesica, and
the female dorsal libiate plate of the bursa copulatrix and...
Three levels of dietary crude protein (8.6, 11.4, and 17.2) were
fed to 24 pony mares to determine the effects on the estrous cycle,
conception rate, and serum progesterone concentrations. Mares were allotted into three treatment groups designated as low protein (LP),
medium protein (MP), and high protein (HP). Following...
The goal of this study was to better understand stream communities through a perspective that might make their structure, organization, and development more understandable. This goal was approached
through the following objectives:
1. To determine the assemblages of stream organisms and define subsystems within a stream community.
2. To explain...
A study was conducted to determine the effects or
temperature, solar radiation, rainfall, and saturated flow
on fecal coliform numbers in sewage sludge-amended soils.
To determine this, four 4.6 X 13.7 m field plots were each
amended in summer and in winter with 800 liters of
anaerobically-digested sewage sludge, and...
An automated multielement flame atomic fluorescence (AF) spectrometer based on microcomputer control was constructed to determine four elements simultaneously. The instrument employs a multiple exit slit monochromator where the light from various exit slits is directed to a single detector with a mirrored funnel. Each element is excited to fluoresce...
The depression of the 1930s had an early effect on the state of Oregon. A
decline in timber and agricultural production resulted in severe unemployment in the
late 1920s. State and local charitable organizations attempted to care for the
unemployed but they did not have the financial resources to do...
Nine feeding trials and four laboratory scale experiments were conducted in this study. The study consisted of: (1) use of grass straw:corn juice (CJ) silages with fishmeal and/or alfalfa hay supplementation in beef heifers, sheep, pregnant dairy heifers, water buffaloes and Hereford cows; (2) use of cull onions:grass straw silages...
The melt intercalation of poly(ethylene oxide) (PEO) between layers of MoO₃ and MPS3 (M=Mn,Cd) is obtained by heating the ground mixture and LiₓMoO₃, KₓMn₁-ₓ/₂PS₃, or KCd₁-ₓ/₂PS₃. The products are characterized by powder X-ray diffraction (XRD). Below the melting temperature of PEO (66 °C), intercalation rates and yields are low. By...
The response of sweet corn (Zea mays L. var. rugosa cultivar
Jubilee) to 12 populations and four nitrogen rates was studied in a
field experiment. Populations ranged from 43, 904 to 329,800
plants/ha with nitrogen levels ranging from 0 to 224 Kg/ha. A systematic
spacing design was used. Plant height,...
The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is a
worldwide pest of numerous agronomic and horticultural plants. Conservation
biological control of this pest can be unreliable due to asynchrony of natural enemies
and certain horticultural practices that have a direct or indirect affect on natural
enemies and the...
The management options chosen by decision makers in
managing wildlife and fisheries have different effects for
diverse user groups. As a result, natural resource management
agencies often seek information to evaluate the effects of
alternative policies on the benefits provided to different
constituencies. Over the past decade, economists have
developed...
During the Pleistocene, an andesitic volcano named Mount
Mazama grew to a probable elevation of 3000 meters in south-
central Oregon. Near the end of the Pleistocene, three diverse
magma types appeared in the eruptive products associated with Mount
Mazama: l)High-alumina basaltic andesite magma associated with an
early plateau and...
This study was conducted to investigate the possible contamination
of foreign pollen at different stages of a wheat breeding
program. These included spaced planted F₂ segregating populations,
replicated yield trials and seed multiplication. The experimental
wheat materials consisted of four different F₂ populations, four
cultivars and two experimental lines.
Two...
Thinning of young Douglas-fir forests has the potential to enhance structural diversity and improve habitat for wildlife. I examined the effects of thinning and thinning intensity on abundance and demographic characteristics of forest-floor small mammals in the Coast Range of Oregon 5 and 6 years after thinning had occurred. Thinning...
The ecological and silvicultural importance of snowbrush,
Ceanothus velutinus, in the areas west of the summit of the Oregon
Cascades was studied. Particular attention has been given its nitrogen-
fixing ability under both field and greenhouse conditions.
On west slopes of the Oregon Cascades snowbrush occurs above
2, 500 feet...
Typical porphyry-type Cu-Mo mineralization predates and underlies the well-known
Main Stage polymetallic veins of the Butte district, Montana. This thesis presents the
first systematic study of the isotopic characteristics of the pre-Main Stage K-silicate and
sericitic wallrock alteration related to the porphyry Cu-Mo stage.
Oxygen and hydrogen isotopic compositions were...
The functioning of marine habitats needs to be understood in the context of the ecological relationships and associations between organisms and the physical and biogenic environment they inhabit. Thus, it becomes important to explore and define habitat features which contribute to these relationships and which are important in the life...
Gallium arsenide shows excellent promise for terahertz generation using mid infrared.
This is for two reasons. First, the indices of refraction for the terahertz (nTHz=3.61 at 1 THz) and mid infrared (nopt=3.431 at 2 μm) are close allowing a long interaction length.
Second, the linear absorption is low at terahertz...
Despite the importance of tropical forest ecosystems in the global carbon cycle, there have been few studies of carbon dynamics in this biome. The magnitude of carbon stocks in the tropics and their changes over time are poorly known since ground-based observations are lacking. In this study, total carbon stocks...
Discrete columns, such as stone and soil-cement columns, are often used to improve the liquefaction resistance of loose sandy ground. In particular, stone columns are considered to increase resistance potential by densification, drainage, and reinforcement mechanisms. For silty soil, the shear stress reduction resulting from the reinforcing effect of stiffer...
Wheat varieties of differential tolerance to Al were used in a
series of nutrient solution experiments to study the inhibitory effects
of Al on growth and nutrient uptake. The pH and the Al and P concentrations
were rigorously maintained to prevent the confounding
effects of Al and P precipitation and...
The production of barley (Hordeum vulgare L.) haploids by crossing with
H. bulbosum is a widely used tool in breeding and genetics. Certain barley
genotypes have low seed set in this interspecific cross, a phenomenon known
as partial incompatibility. Haploid production efficiency and gamete sampling
are important issues with the...
This study involved the use of the two-choice preference test to determine the taste responses of eight, each, of pygmy goats, normal goats, sheep and cattle to ascending concentrations of sucrose (Suc), sodium chloride (NaC1), acetic acid (HAc) and quinine hydrochloride (QHCI). In addition, sheep and cattle were tested at...
Stable expression of transgenes is required for commercial uses of genetically engineered trees. To better understand the stability of transgene expression under field conditions, we studied transgene expression and RNA interference (RNAi)-induced transgene suppression in 2,480 transgenic poplars (460 transgene insertion events) over three years. Stability of expression was assessed...
A pest management program for Tetranychus urticae Koch in Oregon
peppermint was developed based on studies of sampling, plant phenology,
population dynamics and damage thresholds.
A sample size of 45 leaves provided a confidence level of 90%
and a confidence interval of 50%. Estimation of the sample mean was
based...
The records of a population of sex-linked dwarf layers
at the Oregon State Agricultural Experiment Station subjected
to an accelerated selection for hen-housed egg production at
40 weeks of age for a period of over 11 years were analyzed
for selection response, and for the estimation of genetic
parameters. The...
A numerical calculation procedure for the hydrodynamic interference effects between large multiple structures interacting with
linear ocean waves is presented in this study. Viscous effects are
neglected and the hydrodynamic pressure forces are assumed to be
inertially dominated. A finite element method which incorporates
radiation boundary dampers is adopted to...
Habitat use and reproductive success by Merriam's wild turkey
(Meleagris gallopavo merriami) were studied in Wasco County, Oregon,
during 1981-82. This low density turkey population selectively used
forested cover types characterized by a variety of structural
features, species, and age classes. They avoided monotypic forested
cover types, used non-forested cover...