White Pine Weevil

White pine weevil (Pissodes strobi) larval feeding damage is now becoming very evident in southern Ohio. This means that localized weevil populations may be reduced by removing and destroying infested conifer terminals.

Female white pine weevils spend the winter out of sight cooling their six heels in the duff beneath their pine or spruce targets. As temperatures warm in the spring, they climb their hosts to feed and lay eggs in the terminals. Sap oozing from small holes in the terminals is a calling card of this weevil.

White Pine Weevil females spend the winter out of sight cooling their six heels in the duff beneath their pine or spruce targets. As temperatures warm in the spring, they climb their hosts to feed and lay eggs in the terminals. Sap oozing from small holes in the terminals is a calling card of this weevil.

I received an e-mail message today from an arborist in southwest Ohio who included images that showed damage caused by White Pine Weevil. Main shoots (terminal leaders) on white pine and Norway spruce were wilted and brown. Some of the shoot tips were curved into "shepherd’s crooks;" the curling occurs when tender new shoots dehydrate while they are still pliable.

White pine weevil (Pissodes strobi) larval feeding damage is now becoming very evident in southern Ohio.  This means that localized weevil populations may be reduced by removing and destroying infested conifer terminals.  Overwintered females deposit eggs in early spring in the terminals of a wide range of conifers including Douglas-fir, all spruces, as well as Scotch, jack, red, pitch, and eastern white pines.  After the eggs hatch, the resulting white, legless, slightly curved, grub-like larvae tunnel downward just beneath the bark feeding on phloem tissue until pupation.  The...