Use of attractant-baited traps for monitoring and mass trapping of rose chafer, Macrodactylus subspinosus (coleoptera: Scarabaeidae), in Michigan peach orchards

The rose chafer, Macrodactylus subspinosus (F.), is a sporadic pest of fruit throughout Michigan. In 1999 and 2000 research was conducted on the relationship between rose chafer and improved trapping systems in Michigan peach orchards. Traps placed at any height were equally attractive to rose chafer. This is the first study to demonstrate the potential of mass trapping for control of M. subspinosus in peach and the first indication that benefits from mass trapping of this pest could be achieved in a single year of trapping. Overall, the mass trapping trials revealed that M. subspinosus adults quickly move into peach orchards upon emergence from overwintering sites. Substantial damage was recorded in June samples taken approximately two weeks after the first beetles were caught in perimeter traps. Mass trapping as a control strategy will therefore be most effective if traps are in place prior to the predicted first emergence of beetles. Control was best if traps were placed at least 12 m from any orchard border, with optimal catches within the 12 m to 24 m distance. Traps placed on grassy borders recorded more beetle captures than any other habitat recorded. Mean beetle captures were two-fold greater than in perimeter traps in these habitats compared to interior traps. Mean fruit injury in trapped orchards was significantly less than non-trapped orchards. A mark-and-recapture study would suggest beetles moved upwind from their release points. The most beetle were captured in traps adjacent to the release points.