Watch for billbug and chinch bug injury to home lawns in July
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.
If you see dead patches in Kentucky bluegrass lawns, you can check for billbug injury by the "tug test.” Pinch a clump of grass blades in the affected area between your thumb and forefinger, and pull it out of the soil. If billbugs are responsible for the turf damage, you will see several broken-off stems filled with sawdust-like frass from the billbug. Also, look for billbug larvae, pupae and, in a few weeks, adults.
Chinch bugs are most likely to injure drought-stressed turf, especially in lawns with a mix of Kentucky bluegrass and fine fescue. Lawns with a thatch layer are also more susceptible to chinch bugs. The best place to look is in sunny parts of the lawn that appear to be turning brown from drought. Examine the soil surface for chinch bugs in dry afternoons by parting the turf and looking around the base of grass plants. You have to look close because the chinch bugs are only about a 1/8 inch-long. Twenty bugs in two minutes of searching are enough to injure turf. Spot-spraying the infested area with Sevin, Talstar, Allectus or Dylox will help prevent turf damage. Chinch bugs will keep feeding until mid August. Watering frequently helps prevent chinch bug injury.