Measurements on growth traits up to 41 years of age
from 68 progeny sites in eight first-generation breeding
zones of coastal Douglas-fir (Pseudotsuga menziesii
[MIRB.] FRANCO var. menziesii) in the US Pacific Northwest
were used to investigate age trends of genetic parameters
and to determine optimum age of selection. Heritabilities...
Forced-air drying of lumber is economically feasible as an aid to sawmills without dry kilns. Reduced cost of shipping more than offsets cost of drying with forced circulation of air. Investment in equipment is small.
In the Willamette Valley, forced-air drying probably can be accomplished successfully throughout the year. High...
To test the effects of kiln-drying on strength properties of Douglas fir and western hemlock, temperatures to 230 F, conditions for equilibrium moisture contents of 6 percent and 12 percent, and prolonged heating were investigated.
Prolonged heating and choice of conditions for 6 percent or 12 percent equilibrium moisture content...