DIFFERENTIAL SHOOT FEEDING BY ADULT TOMICUS-PINIPERDA (COLEOPTERA, SCOLYTIDAE) IN MIXED STANDS OF NATIVE AND INTRODUCED PINES IN INDIANA

The larger pine shoot beetle Tomicus piniperda, a native bark beetle o f Europe and Asia, was found in North American Christmas tree plantati ons in 1992 in Ohio. Subsequent surveys found it in six U.S. states an d in one Canadian province. The first natural area where Tomicus was f ound to be established was at the Indiana Dunes State Park, in northwe stern Indiana near the Lake Michigan shoreline. Pine stands were surve yed for fallen shoots to determine the extent and range of shoot feedi ng in the park. Within the study area adult Tomicus fed on the shoots of all native pines (Pinus banksiana, P. resinosa, and P. strobus.) as well as the European species (P. sylvestris). More fallen shoots were collected from both P. resinosa and P. sylvestris than expected from their basal areas in the sampled stands. This contrasted with P. banks iana and P. strobus whose shoots were underrepresented relative to the ir basal areas. The relatively high numbers of fallen shoots found for P. resinosa suggests that red pines in the Great Lakes region will ea sily support populations of ir: piniperda.