Description:
One-year-old container-grown Douglas-fir
[Pseudotsuga menziesii (Mirb.) Franco]
seedlings were outplanted on north, east,
south, and west aspects on steep, skeletal
Xerochrepts in southwest Oregon. After 2
years, survival rates were highest on north
and south aspects, but biomass production
(dry weight) was greatest on the west aspect.
Shadecards, used to artificially shade half of the seedlings on each aspect, increased
survival by 27 percent on the south aspect
but had little effect elsewhere. Shadecards
significantly increased height growth on the
west aspect but affected height less on the
south aspect. These results and those of
other studies suggest that shadecards may
increase Douglas-fir seedling survival under
certain conditions.