Cultural practices to maintain
healthy stands and reduce the incidence and severity of SPB attacks are
in harmony with most management goals. Natural stands and plantations can
be equally susceptible to SPB attack when poorly managed; they can be equally
resistant to the beetle when treated properly. Treatments are assigned according
to management objectives and economic considerations.
The forester must understand host and site factors that influence stand
growth and development before he can prescribe practices to reduce losses
from bark beetles. "Standard" silvicultural recommendations
do not apply to all situations. Each region, forest, and resource objective
will require specific practices to maintain or increase the resistance
of host trees to beetle attack. The following guidelines (fig. 3) may
be helpful in developing prevention strategies. Obviously, high-hazard
stands should get first attention.
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