Selected images for larger pine shoot beetle (Tomicus piniperda )
There are several Tomicus species that feed on various conifers. Many are familiar with Tomicus piniperda, the common pine shoot beetle, since it was identified near Cleveland, Ohio in 1992. Two other species, T. minor and T. destruens, are not known to be present in the United States. Probable introduction pathways include: unprocessed logs, fire wood, tree trimmings, and lumber with the bark still attached. Pines are the most common host, although T. piniperda may attack fir, larch, or Douglas fir. T. minor has also been reported on larch. Both T. piniperda and T. minor have one generation per year. For T. destruens, two to three overlapping generations per year are suspected; however, current theories suggest they may actually be multiple broods resulting from mated females attacking multiple trees. After mating, females construct egg galleries within the inner bark and outer sapwood. Eggs are pearly white. After hatching, larvae construct feeding galleries. Larvae are white, c-shaped, legless grubs with an amber colored head capsule which may be as long as 1/8 inch when mature. Pupation can occur, in cells, at the end of the larval galleries or in the bark. Pupae are white with some adult features, including rudimentary wings. Adults emerge and feed by boring into tender pine shoots. This feeding may occur as a mass attack on susceptible trees. Attacks are characterized by reddish-brown boring dust on the bark surface of trees and, if relatively vigorous trees are attacked, conspicuous pitch tubes on the bark surface. Reddening or browning of shoots is also common. Adults are darkbrown, elongate and about 3/16 inch in length. The ends of the wing covers bear features to distinguish between the various species. The head is visible, when viewed from above, and has six-segmented red-yellow antennal clubs. Blue stain fungi or other vascular wilts are commonly associated with these beetles.
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