In collecting our representative flowering
plants, we have endeavored to secure a specimen of each
common genus of annuals and biennials as well as a few
shrubs. The notes, drawings, and classification of fifty of these plants constitute the main part of our thesis. Following are the classifications of various...
Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the Willamette Valley, have decreased dramatically due to loss or degradation of habitat. More research is needed on sustaining the populations of butterflies in...
This book contains descriptions of 15 native and 16 nonnative fish (including origin, distribution, key characteristics, size, distinguishing features, color, diet, and other remarks) found in the Willamette River Basin's seasonal watercourses, with over a hundred photos to aid in identification. It also offers a succinct explanation of the Willamette...
This thesis is a documentation of a selected number of nineteenth century quilts studied by the investigator in the Willamette Valley.
The quilts were located in museums and in individual's homes. A questionnaire, that was developed for this study of quilts, was
filled out as each quilt was examined. Slides...
The future expansion of agricultural production in the Willamette
Valley will depend to a large degree upon the feasibility of introducing
irrigated agriculture on the poorly drained soils in the Valley. A
r earch program has been initiated to investigate the feasibility of
rigation on poorly drained soils with the...
Permeability, effects of age, and water table fluctuations were
studied for nine drainfields in five soil types ranging from well to
poorly drained. Three sites were in Willamette, one in Woodburn,
two in Amity, two in Concord, and one in Dayton soils. Before
permeability of drainfields could be evaluated, methods...
A Willamette sandy shot loam was treated with ZnC1₂, CdC1₂, or sewage sludge to determine the chemical fate of added Cd and Zn in the soil and their influence on the growth of corn and wheat seedlings. Cadmium was added as CdC1₂ at rates of 0, 5, 20, or 80...
The wetlands are distinguished from other lands of the Mid-Willamette Valley by excessive soil moisture. The wetlands, as defined for this study, consist of 20 soil series (in 22 soil mapping units) which are classified by the Soil Conservation Service as having excessive wetness as the major factor limiting their...
Relationships among the surface wind, horizontal synoptic-scale
pressure gradient and topography are studied in the Willamette Valley
in western Oregon. Terrain features alter the standard surface wind-pressure
gradient relationship such that the angle between the surface
wind and the surface geostrophic wind is most frequently 60°.
In winter the surface...
Published April 1981. 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
Published February 1961. 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
Published March 1936. 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
Published April 1935. 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
Published March 1925. 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
Published April 1964. 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
Questionnaires were mailed to farmers in six counties of the
Willamette Valley requesting the kind and size of enterprises and the
gross income received from the enterprises on each farm.
Enterprises were defined both as general livestock or crop categories
and as individual crop or livestock enterprises. Two computer
programs...
Increased seeding rates (7.5, 10, 15.20 pounds per acre) and closer row spacing (12, 6 and 3 inches between rows) resulted in an increased stand of alfalfa during the early years of production. Yield of DuPuits alfalfa was not increased with the additional plants in stand. Vernal alfalfa showed a...
Published August 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
Published August 1981. 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
Published August 1946. 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
Published July 1939. 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
Published August 1938. 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
Published May 1932. 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
Published October 1933. 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
Published December 1928. 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
Clearcutting is a sound silvicultural practice when exercised
in the proper environmental location. Foresters have learned through
bitter experience that clearcutting Douglas-fir forests, located on
droughty south-facing slopes, often leaves uncorrectable regeneration
problems. Thousands of acres of unproductive grass and brush throughout
the Douglas-fir region are unavoidable reminders of inappropriate...
Published June 1945. 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
Published August 1924. 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
This study was initiated to characterize the distribution of Fe-Mn nodules and to elucidate trends of Fe, Mn, and P relative to the intensity of the annual cycles of reduction and oxidation. Nodules were enriched in Fe, Mn, and P relative to the soil matrix making them an integral part...
Hydrologic processes within mineral flat wetlands, along with their
connections to groundwater and downstream surface water in lowland agricultural
catchments are poorly understood, particularly under different land uses. In the three
field studies included in this thesis, we examined infiltration, wetland hydroperiod,
groundwater recharge dynamics, surface runoff generation, and water...
Over one third of the earth’s land surface has been modified to some extent for agricultural purposes. The large global footprint of agriculture, combined with the knowledge that existing reserve networks are likely insufficient for long-term conservation of native biodiversity, has necessitated that agricultural systems contribute to conservation of native...
In the last 200 years there have been significant declines in the amount and structural complexity of oak-dominated forests and savannahs in the Pacific Northwest. Restoring oak systems often involves selectively thinning stands of oaks in order to reduce competition for sunlight. In choosing which trees to cut, land managers...
Quercus garryana dominated plant communities are found in
the interior coastal valleys and on foothills from southeastern
Vancouver Island, British Columbia, south to San Francisco,
California. They occur as savannas, intermixed with a variety of
conifers, and in almost pure stands. The diversity of habitats
occupied by the species and...
In the United States, many of the thorniest natural resource conflicts occur on private lands. This is especially true in the Willamette Valley of Western Oregon where the hallmark habitat type, Oregon white oak woodland and savanna, is imperiled. Almost exclusively found on private land, Oregon white oak is threatened...
Vertically shoot positioned (VSP) training systems are common in Oregon's Willamette Valley, where deep fertile soils and high regional precipitation task growers with curbing vegetative vigor within this system. Management strategies, such as canopy hedging and cluster-zone leaf removal, are used to improve microclimate within the canopy and around the...
The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity....
The Willamette Valley of Oregon has high rates of winter precipitation that cause leaching losses of residual fertilizer nitrogen (N) as nitrate (NO₃). Cover crops may have potential to mitigate N loss. Shallow groundwater was sampled for 11 years from plots planted in summer vegetables with and without winter cover...
Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, and home landscapes increases so does demand for information on the basic biology of a group of species that have...
Pedestrian distraction at roadway crossings has been correlated with a higher risk of pedestrian-vehicle collisions due to the pedestrian's cognitive, visual, and motor attention being drawn to a wide variety of secondary tasks.
This study is different from previous field studies of pedestrian midblock crossings in that the geometric layout...
Role of temperature and photoperiod on development of the filbert leafroller, Archips rosanus L., (Lepidoptera: Tortricidae) from the Willamette Valley, Oregon was studied in the laboratory and in the field. Both temperature and photoperiod had a significant influence on the developmental rate of this species from neonate larva to adult...
I monitored demography, movement, and reproductive behavior of gray-tailed voles, Microtus canicaudus, in experimental habitat patches with and without corridors. I tested the hypotheses that reproductive rate, juvenile recruitment, and population size and growth rate would be affected negatively by immigrants that were introduced to resident groups (+ male and...
Rotating wheat with other crops is a common practice in the Willamette Valley of
western Oregon. Depending upon previous crop and soil type, current N fertilizer
recommendations for wheat in the Willamette Valley vary widely. Excessive fertilizer
poses environmental risk, whereas lower N inputs than required by the crop represent...
'Golden Delicious' winter squash (GDWS), Cucurbita maxima Duchesne, provides significant amounts of pollen (24 mg) and nectar (236 μl), but with a low reward of 14% nectar sugar. The quantity of nectar produced per GDWS flower differed between sites and floral sex. The GDWS male flowers had 25% higher sugar...
The effect of primocane removal and training time on yield components and cold hardiness of 'Marion' trailing blackberry was studied. In 1991, primocanes were either not cut, or cut at ground level from plants on a single occasion at one month intervals from late April to late July. Four canes...
Three different ground cover management strategies were compared at the OSU research vineyard near Alpine, Oregon. Botanical diversity was actively increased in two diverse treatments. Another treatment was botanically uniform and contained creeping bentgrass (Agrostis stolonifera). The composition of the vineyard floor vegetation and grapevine performance as affected by the...
Published September 1982. 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
A step-by-step guide to riparian tree and shrub planting in the Willamette Valley. Provides information on project planning, plant materials, site preparation, planting techniques, site maintenance, and monitoring and evaluation. Intended to help landowners, watershed council members, agency personnel, and others communicate about, plan, and implement woodland plantings near streams...
This study integrates various vineyard practices that may improve nitrogen availability to the vine, particularly during ripening. Different strategies aimed at increasing yeast assimilable nitrogen in the fruit at harvest have been evaluated. This study seeks to improve fermentation behavior and wine quality through vineyard practices used for nitrogen management....
Crop thinning trials were studied during two seasons at two locations in the northern Willamette Valley of Oregon. At Willakenzie Estate (site #1), research vines were Pinot noir clone Dijon 113 on 3309 rootstocks trained to a double Guyot. Vines were established in 1996 at a spacing of 2.5 x...
Soil response and function were investigated following the adoption of an integrated reduced-tillage and cover-cropped vegetable system in the Willamette Valley of Western Oregon. The experiment was conducted over three cropping seasons (2002-2004) at the Oregon State University Vegetable Research Farm (Corvallis, OR). The design was a randomized complete-block with...
The Oregon Long-Term Soil Quality Project was initiated to identify soil
properties that respond rapidly to alternative management practices. Such practices
included winter cover cropping, which was implemented at two experimental research
stations and several grower fields throughout the Willamette Valley. The goal of this
thesis was to identify the...
Directly below commercial mint fields, percolation in excess of 10 ppm of nitrogen as nitrate (NO3 --N), the EPA drinking water standard, occurs for much of the year (Figure 1, page 2). Concentrations rise rapidly after irrigation starts in June, indicating that this nitrogen is being pushed through by irrigation...
Published December 2003. 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
Relatively little is known about wintering bird communities in lowlands of the Pacific Northwest, yet, the condition of winter habitats potentially can pose a major constraint on bird populations. I initiated a study to determine: (1) Which avian species use lowland riparian and wetland habitats in the Willamette Valley during...
Low-permeability geologic units may offer significant chemical and hydraulic protection of adjacent aquifers, and are important for managing groundwater quality, especially in areas with significant non-point source contamination. Nitrate in the Willamette Valley is attenuated across the Willamette Silt, a semi-confining unit overlying a regionally important aquifer. To quantify the...
Published January 1931. 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
Published June 1927. 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
Published June 1923. 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
Many agricultural sustainability issues are related to biological processes which are central to the ecological function of soils. Soil physical properties are the architecture in which these processes are carried out. Cover crops hold promise as one of the techniques which can ameliorate poor soil structure and improve bulk density...
The nature and extent of niparian vegetation change from 1972 to
1981 in the Willamette River Greenway in Benton and Linn Counties,
Oregon was quantitatively investigated. The study was primarily by
aerial imagery analysis and associated field verification. A classification
of vegetation and land cover within the study area was...
Data from fertilizer experiments with potatoes in the Willamette Valley from 1961 through 1971 show that responses have been measured from nitrogen, phosphorus, potassium, magnesium, and lime. Responses from these nutrients have been related to soil and/or plant analysis values. In recent years most of the potato production has moved...
This publication is part of a 1-year project funded by the Oregon Department of Agriculture, Alternatives to Field Burning Program. Crop substitution is one strategy for reducing smoke from field burning. The objective of the project was to evaluate the potential for hybrid poplar as an alternative crop for poorly...
In ecological restoration, species that are sown to increase the native plant
diversity range in establishment ability. Some species readily establish, while others
rarely do. This study set out to investigate some of the potential processes influencing
species establishment, as well as the traits that are associated with the success...
In 2003 and 2004 vigor zones were delineated in two commercial vineyard
sites based on vine growth variation to assess fruit and wine phenolic chemistry. In
2004, the effects of shading on the accumulation of phenolic compounds were also
investigated. Model extractions were done from the shading experiment and the...
Groundwater nitrate contamination is a well-documented issue in the Southern Willamette Valley (SWV) of Oregon, as a Groundwater Management Area (GWMA) has recently been declared. As a GWMA, groundwater nitrate monitoring must occur until regional concentrations are below 7 mg/L NO3-N. However, the presence of temporal variability can make it...
Previous studies of bird communities in the mid-Willamette Valley, Oregon, indicated that Oregon white oak (Ouercus garryana) stands supported more cavity-using bird
species than sympatric stands of Douglas-fir (Pseudotsuga menziesii). Mature Oregon oak stands are being harvested and few are regenerating. I compared cavity availability for hole-using fauna among 10...
This thesis investigates the success of and challenges facing small farmers operating direct marketing farm businesses in Oregon's Willamette Valley. This qualitative study utilizes participatory methods to gain the unique perspectives of small farmers regarding their success and challenges. Small farms are important players in local food systems and ensuring...
Birds perform valuable ecological functions and are useful environmental indicators. Avian distributions and diversity are predicted to change over the next 50 years. Little information exists on the role of local and regional conditions in fluctuations of avian communities over time. Historic datasets present a legacy of information that helps...
This investigation has analyzed and described the impact of
place on one of man's activities -- the production of sugar beet seed.
It is apparent that in this activity man's relationship to the earth is
especially close and dependent upon a number of factors. These
are localizing factors. Sugar beets...
Wheat is an important cereal crop in the Willamette Valley of
Oregon and the stiff-strawed, high yielding winter varieties are
the predominate types grown although spring varieties are not uncommon.
Because of the mild, often open winters; present in the
Willamette, it is not unusual to be able to seed...
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...
A study was undertaken in the Willamette Valley, Oregon, to document
1971 land use patterns as well as land use change in a smaller study
area in the 16 years prior, and to relate these to soil characteristics.
Quantification of these inter-relationships was aided by use of computer
tabulation and...
Modern agricultural erosion was studied using ¹³⁷Cs from
fallout as an indicator of erosion/deposition. The study area was a
285 ha agricultural watershed in the hilly western margin of the
Willamette Valley, a high winter rainfall zone in which fall-planted
crops are commonly grown.
Objectives of the study were (i)...
Seed yield in perennial ryegrass is the product of yield components
that develop during the life of the plant. Crop yield potential is
defined by the number of fertile tillers, spikelets per spike, and
florets per spikelet. It has been shown that perennial ryegrass
realizes only a small percentage of...
There are two major problems associated with soil acidity and
lime response investigations:
A. Determining how much lime (100% "available" CaCO₃ equivalent)
is required to raise a soil pH (or degree of acidity) from its
existing level to a specified level - presumably where need for
lime is eliminated.
B....
Body size explains much of the interspecific variation in the physiology, behavior, and morphology of birds, such as metabolic rate, diet selection, intake rate, gut size, and bill size. Based on mass-specific metabolic requirements and relative energetic costs of activities, being a certain body size has both advantages and disadvantages....
This study investigated the local and sustainable food movements in the Willamette Valley of Oregon. The aim of the research was to better understand the current condition of the phenomenon, what it means to the communities studied and the future role it will play in the state. Other research objectives...
Preservation of rare plant species often requires establishment of new populations. Survivorship surveys are the most common method of post-introduction monitoring. However, they provide an incomplete picture of establishment success. This study is an attempt to develop a model for determining establishment success by determining the factors affecting recruitment in...
Chewings fescue [Festuca rubra L. subsp. fallax (Thuill.) Nyman] is a desired turfgrass with dense sod forming capabilities and superior shade tolerance. Thermal residue management (open-field burning) has traditionally been used to remove post-harvest residue and maintain seed yield over the life of the stand. However, alternative non-thermal residue management...