Abstract

Ethanol-baited bottle traps were used to monitor spring flight activity of the ambrosia beetles Xylosandrus crassiusculus and Xylosandrus germanus in Ohio, Tennessee, and Virginia. The traps were deployed at three different heights to determine if height influenced captures. X. germanus was captured in all three states, while X. crassiusculus was captured in TN and VA only. Traps 0.5 m above the ground captured more X. germanus than traps at 1.7 or 3.0 m. Traps 0.5 or 1.7 m above the ground captured more X. crassiusculus than traps at 3.0 m. In TN and VA, first activity of X. crassiusculus and X. germanus occurred from mid-March to early April. In OH, first activity of X. germanus occurred early to mid-April. Analysis of attacks by X. germanus on Cornus florida revealed that more than 90% of the attacks occurred on the main trunk within 1 m (3 ft) of the ground. Monitoring will be most effective when traps are suspended 0.5 or < 1.7 m above the ground for X. germanus or X. crassiusculus, respectively. To detect first flight of X. crassiusculus or X. germanus, traps should be deployed by early to mid-March in TN and VA and late March in OH.