Management factors used for studies on potato scab
control were evaluated for their effect on tuber russeting
and related biochemical and anatomical parameters
during 1971 and 1972.
Russet Burbank potatoes were irrigated in 1971 to
maintain high available soil moisture (between 90% and
field capacity) for 0, 3, 6 and...
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...
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...
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. )...
Soil erosion by mass wasting is the major problem on forest
lands of the Pacific Northwest, The clay fractions of soils from a
large number of sites in Oregon's Western Cascades were characterized
in order to determine the relationships of various clay materials to
mass movements. Each site was either...
Symbiotic associations are established between non-leguminous
(actinorrhizal) nitrogen-fixing flowering plants and two categories
of microorganisms: mycorrhizal fungi and a filamentous actinomycete.
The actinomydete induces nodule formation and produces nitrogenase,
the enzyme responsible for the reduction of atmospheric nitrogen to
a form available to higher plants. The mycorrhizal fungus is found...