Net photosynthesis was measured for photosynthetic light efficiency and capacity on two-year-old plants from eight different seed sources in three measurement periods. The measurement periods corresponded to the physiological periods 1) prior to bud swelling, 2) after needle elongation, and 3) predormancy. Measurement period differences in both photosynthetic efficiency and...
Nine species of ectomycorrhizal fungi were grown in liquid media over a pH range of 2-7. Species fell into five major groups: (1)
growth significantly best only at the optimal pH, (2) growth increased with increase of pH, (3) significantly best growth spans three pH units, (4) spans four pH...
Chapter 1 Growth and Survival of Root-Wrenched Douglas-fir Seedlings Root wrenching of seedlings (severing the roots 15 cm below the soil surface) was investigated as a nursery practice to improve growth and survival of field-planted Douglas-fir from six local seed sources
in the Pacific Northwest. At lifting, shoots of wrenched...
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...
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...
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...
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 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...
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...
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...