A comparison between crown competition factor and basal area as to their ability to predict future basal area growth was conducted. It was shown that for a single age and site combination there was no real difference between the growth prediction ability of the two measures of stand density.
It...
Root biomass studies were conducted in an old-growth stand of
conifers in the western Cascades of Oregon. The root systems of three
Douglas-firs (Pseudotsuga menziesii var. menziesii (Mirb. ) Franco)
with diameters at breast height of 94, 110, and 135 cm were excavated
and weighed to provide a basis for...
The form of a tree stem and the properties of the wood comprising
a stem may be determined by the strength requirements of
that stem. If this is true, a tree will react physiologically to
stresses which are imposed on a stem. This study was designed
to investigate the influence...
Populations of Douglas-fir seedlings from interior British
Columbia, Vancouver Island, and Arizona received six bi-weekly
foliar spray applications of the growth regulators IAA, CCC, and
B-995, each at three concentration levels under controlled environmental
conditions. Large differences were found among the three
populations in their responses to the growth regulators....
The Oregon State Cooperative Seed laboratory uses two methods for testing the quality of Douglas-fir seed lots. The first of these is a straight-forward germination test without any pre-treatment of the seed, involving a period of 42 days in the germinator at alternating 20°C.-30°C. temperatures. The second method consists of...
A rapid and efficient procedure that required no partitioning was developed for the purification of abscisic acid (AbA) from the needles of Douglas-fir seedlings. Extracted needle pigments were removed by a
PVP column and the eluted AbA was concentrated on a DEAE column. The AbA was eluted from the DEAE...
The inter-relationship of salmonberry and Douglas-fir on cutover areas was investigated in the Coast Range of western Oregon. Animal influences affecting the survival of Douglas-fir in a salmonberry
habitat were also investigated. The autecology of salmonberry was considered first by formulating a mathematical model to characterize the lateral encroachment of...
Two studies were undertaken in search of a method or methods which might improve the survival of planted Douglas-fir seedlings on severe sites. The first, or preliminary study involved the planting of 2-0 Douglas-fir seedlings on southerly aspects, using nine techniques, including a control. The second, or main study involving...
An energy balance analysis was performed on each of four
transplanted Douglas-fir [Pseudotsuga menziesii (Mirb.) Francol
seedlings growing on two cutover sites in southwestern Oregon. The
two sites were a clearcut and a partial-cut (shelterwood) side by
side, with a pair of seedlings used on each site. One seedling of...