Conophthorus sp. (Scolytidae)
Eleven species in western North America.
||Small shiny black beetle with barkbeetle features. Adult
is one of the injurious stages. Adults often burrow along axis of cone. Females
||Legless, small, curved, wrinkled, ivory coloured grubs feed
indiscriminately throughout the cone.
||Adult beetle bores into an immature second year cone in
pines. Usually each cone is attacked by one pair of beetles, boring into
the stalk of the cone and tunnelling into the axis. The female lays its eggs
in the tunnel, which now becomes an egg gallery, then vacates the cone, plugging
the entrance hole with frass. Larvae are present July-August, pupate and
transform into adults which remain in the cone until the following spring.
The attack kills the cone and destroys all potential seeds. Damaged cones
drop to the ground in early summer.
Periodic outbreaks may destroy 25-75% of a cone crop over large acreages.
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