Date: 3/30/99

Time: 8:05

Type: Symposium

Number: 92

Diversity of native natural enemies of pine shoot beetle and their potential impact on biological control

*D.G. McCullough, Dept. of Entomology and Dept. of Forestry, Michigan State University, East Lansing, MI 48824
Contact e-mail: mccullod@msue.msu.edu

Pine shoot beetle (Tomicus piniperda L.) (Coleoptera: Scolytidae) is an exotic bark beetle that was first discovered in North America in 1992 and is known to be established in at least 220 counties in the North Central region of the U.S. and in parts of Ontario. Parent adults colonize pine brood material such as recently cut or dying pine logs and stumps early in spring . After emerging from logs, progeny adults feed in shoots in live pines during the summer. Spring activity of pine shoot beetle parent adults typically begins 4 to 10 weeks earlier than activity of most native scolytids such as Ips pini Say. Concerns arose over the possibility that this early activity would enable pine shoot beetle to escape native predators such as Thanasimus dubius (F.) (Coleoptera: Cleridae). We evaluated interactions among pine shoot beetle, T. dubius, native phloem-feeders, and other native natural enemies for 2 years in red pine stands. Funnel traps, weekly observations of activity, and rearing studies provided information on the phenology, abundance, and diversity of natural enemies in the pine ecosystems. Results suggest that T. dubius and 3 other native predators were active earlier in the spring than previously reported. Other native natural enemies were recovered from logs and may attack developing pine shoot beetle larvae in brood logs. Introduction of exotic predators for pine shoot beetle does not appear necessary at the present time.

This abstract may not be cited or reproduced without permission from the author(s).