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...