This paper involved the estimation of a series of fare
equations in order to ascertain the effects of actual and
potential competition by Southwest on markets for air
travel. The results indicate that pricing strategies differ
depending on Southwest's presence on a route, which is not
consistent with the theory...
In terms of production forestry, more often than not any species that is not the crop
species is considered a competitor as they are using finite growing resources that would
otherwise be available to the crop species. With specific regard to Douglas-fir
(Pseudotsuga menziesii (Mirb.) Franco) production in the Pacific...
Computer simulations and experiments were used to determine
the basis for skewness and inequality in size structures
(frequency distributions of Individual plant sizes) prior to
self-thinning mortality. In simulated stands, density-dependent
neighborhood heterogeneity caused variability in the growth rate
of individuals with the same size, and such variability caused
skewness...
"Crested wheatgrass, beardless wheatgrass, and big bluegrass were
seeded as overstory grasses. Streambank wheatgrass, canby bluegrass,
bulbous bluegrass, and Ladak alfalfa were seeded as companion species.
Pure and mixed stands were seeded on sagebrush-bunchgrass
range in eastern Oregon to compare yield and competitiveness. The
grasses were planted in 1956, 1957,...
Ungerminated seed and recent germinants from 39 open-pollinated Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco)
families were planted in each of three competitive environments in order to determine the degree to which growth differences among families are influenced by competitive environment, seed weight, and
date of emergence. The three competitive...
Sitka alder (Alnus sinuata (Regel) Rydb.) dominates many lodgepole pine (Pinus contorta ssp. latifolia Dougl.) sites following clearcutting in the Montane Spruce zone of the southern interior of British Columbia. The objectives of this study were to examine the effects of the sitka alder-dominated shrub community on the performance of...
Competitive interactions between Douglas-fir seedlings (Pseudotsuga menziesii), and seedlings of a nitrogen-fixing hardwood
associate, red alder (Alnus rubra), were investigated in an addition series experiment. The primary objective of the research was to identify and quantify key processes underlying intra- and interspecific competitive interactions of Douglas-fir and red alder seedlings....
When Douglas-fir and red alder grow in mixture, interactions between the two species can be competitive, facilitative, or a combination of both over time. A number of factors have recently led to increased interest in managing these two species together for commercial production, and ongoing investigations are yielding important information...
The response of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) saplings to various levels of brush overtopping when growing on three north-facing sites in the Oregon Coast Range was investigated for two consecutive years. A fisheye (hemispherical) photographic technique combined with a digitizing computer system was used to determine the percentage of...
