The beetle tunnels through The pine shoot beetle (Tomicus piniperda L.) is an introduced pest of pines. It was first discovered in the U.S. at a Christmas tree farm near Cleveland, Ohio, in July 1992.
Shortly thereafter, USDA APHIS Plant Protection and Quarantine (PPQ) implemented a regulatory program and quarantines on at-risk pine commodities, like logs and lumber with bark, Christmas trees and nursery stock in known infested areas.
Despite the regulations, T. piniperda subsequently spread throughout the northeast and north central U.S.
Sources: USDA APHIS, CABI, Penn State University Extension
The facts about Pine Shoot Beetle Life cycle: The egg is white, shiny and oblong, about 1 mm long. The larva is a legless, whitish grub with a curved body and a brown head capsule. The mature larva is 4-5 mm long. There are four larval instars. The pupa is white and resembles the adult insect in size and general form. Newly emerged callow adults are straw-yellow and darken with progressive sexual maturity. The mature adult has a dark-brown head, thorax and elytra, but the latter may sometimes be reddish-brown (as in T. minor ).
Damage: The beetle attacks new shoots of pine trees, stunting the growth of the trees. The pine shoot beetle may also attack stressed pine trees by breeding under the bark at the base of the trees. The beetles can cause severe decline in the health of the trees, and in some cases, kill the trees when high populations exist.
Symptoms: The presence of pine shoot beetles is disclosed by fallen and tunnelled shoots on the ground as well as typically stunted pine crowns in cases of high population levels. It is not possible to separate the shoot damage caused by T. piniperda from that caused by T. minor (or T. destruens ), unless the beetles are still inside the shoots.
After the spring flight, the adults of T. piniperda disclose their presence in fresh pine timber or weakened trees by the typical boring dust containing brown bark and white wood grain (unique for this species), which is visible in bark crevices adjoining the entrance holes. In late summer, clusters of exit holes (about 1.5 mm in diameter) reveal successful brood emergence. Peeling off the bark will show longitudinal egg galleries with egg niches in early season, and larval galleries in late season.
Control: Chip or burn any culled pines to remove breeding sites. Cut stumps low to the ground and apply appropriate insecticide to prevent larval development in late April/early May. During the growing season, scout for dead or bent shoots on the upper half of the tree. Shoots may be yellow or red and will have small holes where beetles have entered and exited. Clip off and open suspected shoots to examine for the beetle. Evaluate results and update records at the end of the season.
Use trap logs to attract breeding parent beetles by systematically placing freshly cut pine trees or logs along the edges of the field in early spring. The trap logs must be chipped or burned after breeding occurs but before new adults emerge.
Gyorgy Csoka, Hungary Forest Research Institute, Bugwood.org; Steve Passoa, USDA APHIS PPQ, Bugwood.org
