Developmental thresholds and thermal unit (degree
day) requirements for eggs, different larval instars,
pupal stage and preoviposition period were determined
for the obliquebanded leafroller (OBLR), Choristoneura
rosaceana (Harris). Separate thresholds and degree day
requirements were determined for males and females, but
differences between the sexes were not significant.
However, there...
The process of biological nitrogen fixation involves the enzymic
reduction of atmospheric nitrogen (N₂) to ammonia (NH₃). The
enzyme which catalyzes this reduction, nitrogenase, does not exhibit
a high degree of substrate specificity. It also catalyzes the reduction
of acetylene (C₂2H₂) to ethylene (C₂H₄). The reduction of
C₂H₂ to C₂H₄...
In the last 30 years, birdsfoot trefoil (Lotus corniculatus L. )
has been recognized as a great potential source of forage. Since the
1930's, many studies have been reported in relation to birdsfoot
trefoil characteristics, including some directly related with the
association between seed yield and its components.
The purpose...
A study of nucleate boiling of water, four alcohols and
three ethanol-water mixtures was conducted in a vertical
thermosiphon reboiler. The test section consisted of a 1/2-
inch diameter electrically heated stainless-steel rod
jacketed by a 15-inch long pyrex glass tube. Two different
inside diameters of the glass tube corresponding...
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...