Bitterbrush [Purshia tridentata (Pursh) DC] plants were burned or
clipped, fall and spring, under different soil moisture conditions on
two sites in east-central Oregon. Treatments, on plants of an erect
growth form on the Juniperus/Artemisia-Purshia site resulted in 38% of
the fall-clipped and 40% of the spring-clipped plants sprouting. None...
Four studies were conducted. First, mountain big sagebrush communities were burned at Lava Beds National Monument, California, and The Crooked River National Grassland, Oregon. In two years at Lava Beds, basal cover of Idaho fescue in one community and Thur- ber's needlegrass in one of three communities did not recover....
Bitterbrush (Purshia tridentata (Pursh) DC.) is one of the most widely distributed shrubs in western North America. Its value as a browse species has been recognized for more than half a century. Recent concern for the ecological significance of shrubs in natural ecosystems and the serious depletion of many big...
A pharmacognostic study was made of the root of Heracleum
mantegazzianum, an umbelliferous species which is of value as a
source of natural coumarins.
Three groups of seeds were tested to determine the presence
of a germination requirement for moist cold and the possible value
of gibberellic acid in obviating...
An analog simulation of the postural control system (PCS) of a
dog is used to illustrate how modern systems simulation can be applied
to a study of complex life systems. Even though many bold
assumptions were required to adequately simplify the PCS model, the
simulation provided intuitive insight and gave...
A static analysis of quadruped biomechanics, combined with
observations of longitudinal postural movement, has revealed important functional attributes of the postural control system. Since
posture is an outward expression of central nervous system (CNS)
behavior, these results may contribute to an understanding of integrative
functions of the CNS.
Beginning from...
Stem form development of trees in response to wind has been established in the literature to be a response to stem sway induced by the wind. The response is manifested in modifications to height and diameter growth which strengthen the stem against wind stresses. Experiments in the literature show that...
Field and laboratory studies were conducted on volcanic ash from Yakima, Moses Lake, Spokane, Washington, and Moscow, Idaho, three weeks after the May 18, 1980, eruption of Mt. St. Helens in southwestern Washington. These studies examined 1) the chemical, physical, and water retentivity properties of the ash, 2) the effect...