Three methods--radial compression strength, color indicators of decay and micro-toughness, an examination of tracheid fracture patterns, were evaluated for detection of early decay and for application to field use. Three-eighth-inch diameter plugs 3/4-inch long, cut from the sapwood and heartwood of a Douglas-fir pole free of decay, were decayed by...
A three-year investigation was conducted during 1980-1982 to
evaluate the potential of using herded sheep as a silvicultural tool
to suppress brush in Douglas-fir (Pseudotsuga menziesii) plantations
of Oregon's Coast Range. Sheep browsing of Douglas-fir was highest
in May soon after bud break. Averaged over the 2 years of grazing,...
Experiments were conducted to determine if the plagiotropic
growth habit of rooted cuttings of Douglas-fir might result from a
system favoring the accumulation of indoleacetic acid in the adaxial
side of the shoot in response to vertical placement.
Actively growing excised branch terminals were subjected to
gravitational disorientation to determine...
The relation of bud and cambial activity to root initiation and
elongation in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco)
stem cuttings was studied through two successive growth cycles.
Stem cuttings of current season's growth were taken periodically
from field-grown Douglas-fir trees to determine: (1) origin and
development of root initials; and...