 The
western pine bark beetle initially attack midway up the tree. Pine
Bark Beetles
pass through the egg, larval, pupal,
and adult stages during a life cycle that varies in length from
about 2 months in warm weather to 10 months in cool weather. All
stages are completed beneath or in the bark of infested trees,
except for a brief period when the adults fly to find new trees to
attack.
Among the western bark beetles, Ips is second in destructiveness
only to Dendroctonus. Twenty-five species are currently recognized
in the West. Predominantly, they attack pines and spruces. Ips
beetles vary in size by species. Adults are cylindrical in shape,
usually dark brown to black and range in length from 1/10 to 1/4 of
an inch. Ips complete their life cycle in as few as 25 days,
depending on species and temperature.
Turpentine Beetle. This beetle is large for a bark beetle, about 1/3
inch long. It attacks pine trees at the base of the trunk, and may
also breed in stumps. Black turpentine beetle grubs feed together
and excavate large patches under the bark. A common characteristic
of this beetle's attack is the presence of a glob of pitch, about
1/2 inch in diameter, at the exit hole.
Test plots using several different methods have been tried in an
effort to control this extreme infestation. The
system
we have put together appears to have had the greatest results.
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