Update on grubs and chafer beetles
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
Did you have grub damage last fall or this spring?
If the answer is yes, then now is the time for professionals to apply Merit, Mach 2, or Arena, and for homeowners to apply GrubEx or Bayer Season-long Grub Control. These products work best when applied in July or early August. A grub treatment with one of these products now will prevent turf injury from grubs in the fall and next spring. Daily-irrigated lawns are usually tolerant of grubs and do not need to be treated, but occasionally Japanese beetle will damage an irrigated lawn. Low maintenance lawns without any irrigation are susceptible to damage for the European chafer. Both of these beetles are active throughout the southern half of the Lower Peninsula, south of Midland and Muskegon. Recently, European chafer has been found in the Traverse City area, and in a few other isolated locations in the northern Lower Peninsula.
European chafer beetles out in full force
Bob Bricault, horticulture Extension educator in Ann Arbor, and others have reported “oodles” of light brown beetles gathering on the tops of trees in lawns just before or after sunset. These are the European chafer beetles emerging at dusk to mate and eventually lay eggs. They do not feed as adults, so they won't injure trees and shrubs. However, lots of beetles now mean you may have lots of grubs in your lawn in the fall.