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. )...
High speed photodetectors are a necessary element in
broad band digital and analog optical communication systems.
In this thesis easily integrable planar high speed
photodetectors made on undoped semi-insulating (SI) GaAs
substrates are modeled and tested. The fabrication process
of the detectors is fully compatible with GaAs
metal-semiconductor field effect...
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...
The study was conducted on the Ochoco National Forest in
central Oregon. Vegetation-soil relationships were evaluated for the
following objectives: 1. Develop a sound ecological foundation on
which total land management decisions may be based. 2. Evaluate
forest succession, stocking, and growth to improve management.
3. Develop accurate range condition...
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...
Whitebark pine (Pinus albicaulis) is an iconic North American high-elevation tree species currently threatened by climate change, mountain pine beetle, and white pine blister rust (WPBR), a lethal disease caused by the non-native fungal pathogen Cronartium ribicola. In collaboration with the USDA Forest Service Dorena Genetic Resource Center, germplasm was...
Recent emphasis on range improvement of sagebrush-bunch-grass
types in Oregon has underscored the need for better understanding
of their importance to deer winter range management. The
objectives of this study were to evaluate the impact of various sagebrush
control practices on the composition, production, and utilization
of deer forage plants...
The purpose of the research was to computerize mathematical
procedures for the analysis of range vegetation and environmental
data. The specific objectives were as follows:
1. to develop and apply computer techniques to the classification
of vegetation in order to provide a phytosociological
framework within which to investigate the ecology...
Sheep and cattle dietary preferences were determined on tall fescue-subclover ( Festuca arundinacea-Trifolium subterraneum) and
perennial ryegrass-subclover (Lolium perenne-Trifoliuni subterraneum)
pastures in western Oregon during the spring and summer periods
of 1964 and 1965. Esophageal-fistulated Willamette ewes and
Hereford and Hereford-Angus yearling cattle were grazed separately
on each pasture mixture...