There are a number of wood properties which affect the quality of forest products such as lumber and pulp. Of these, wood density is considered by some to be the single most important physical characteristic because it is an excellent predictor of strength, stiffness, hardness, and paper-making capacities. Accurately assessing...
Chemical and microbial analyses were made at four seasonal intervals on soil horizons under red alder, conifers, and mixed
alder-conifers at the Cascade Head Experimental Forest, established in 1937 by the U. S. Forest Service near Otis, Oregon.
Microbial analyses showed that although plate counts of molds and bacteria fluctuated...
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...
The relative freezing resistance of tissues in the stem, foliage and buds of terminal twigs from Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) was investigated at about ten-day intervals from summer until the following spring. Tissues from growing twigs collected before development of dormancy had no freezing resistance and were killed immediately...
A mathematical model has been developed to describe the growth
of individual Douglas-fir trees under a variety of stand conditions and
management schedules. The model was developed using empirical
data from open-grown trees and reducing growth capacities of height,
stem, and crown as functions of intertree competition indices. Any
initial...
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...
The main objective of this investigation was to evaluate relationships
between the production and utilization of forage and deer
browsing of hand-planted Douglas-fir seedlings. A secondary purpose
was to study some effects of selected physical and biological
site factors on the survival and growth of fir seedlings.
Field work was...
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...
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...
Cell aggregate size in both Douglas-fir and poplar suspension cultures was reduced by the addition of the chelator compounds EDTA and CDTA at concentrations under 100 ppm. Reduced cell aggregate size increased growth efficiency of suspension cultures of both species. Cell aggregates 550 j.z. or smaller in size were used...
The objective of this study was to assess the effects of
forest management intensity on long-term productivity of Pacific
Northwest Douglas-fir forests. The components of management intensity
included rotation length, timber utilization standard (whole
tree or bole only), method of slash treatment (remove/burn or leave)
and fertilization practice (urea nitrogen...
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...
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 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...
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...
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...
This study was undertaken to determine the
effects of different chilling treatments during the dormant
season upon growth of Douglas-fir seedlings0 In
addition it was planned to determine whether seedlings
native to various geographic areas differ in their chilling
requirements0
The hypotheses were advanced, based on previous
studies, that chilling...
Genetic variability in natural populations of Douglas-fir was
studied at molecular level by investigating the variations of some
primary gene products, i. e. enzymes. Using the techniques of disc
gel electrophoresis and biochemical staining, the isoenzyme patterns
of leucine aminopeptidase, esterase and glutamate oxaloacetate
transaminase are characterized in young seedlings...
The subject of this study was the determination of the changes
in photosynthesis, respiration and transpiration in two ecotypes of
Douglas-fir as caused by decreasing soil moisture content. The photosynthetic
rate was also correlated with the relative turgidities of
needles.
All the above processes were greatly affected by decreasing
soil...
The effects of winter plant moisture stress (P145) on bare-root 2+0 Douglas-fir (Pseudotsuga menziesii (Mirb.) Frañco) seedlings during nursery lifting and processing were studied. Seedlings were undercut at Ca. 4, 12, and 20 atm PMS during mid-February. Half of the seedlings undercut at 12 and 20 atm were not moistened...