You Are Here: Management Updates 1998 Archive September 1, 1998

Date: September 1, 1998
Category: Insects
Subject: White Grubs, Hyperodes Weevils, Cutworms, Chinch Bugs

White grub activity is on the increase across the Commonwealth. Most species began laying eggs in July and grubs can be found in most the usual places. Soil moisture when grubs were first hatching was good, particularly in the eastern part of the state, so grub populations probably will be "moderate" in most locations this year. It is too late to use slow acting products like Merit now, but some of the other traditional insecticides (for example, Turcam or diazinon BUT NOT ON GOLF COURSES can be used through the end of August. Grub populations that need attention in September probably should be treated with Dylox, the fastest acting material currently available. Remember to sample first and only treat the areas where grub populations are high enough to warrant attention.

Cutworm activity appears to be fairly "typical" this year - a range of caterpillar sizes throughout the summer as generations overlap. Fortunately, cutworms still are fairly easy to control with several of the traditional materials. Remember that studies in kentucky suggest that eggs are removed from the tips of leaf blades during mowing, but caterpillars are able to hatch out from those eggs and migrate back to the green. Chris Williamson (now with TruGreen ChemLawn) and Dan Potter (University ofKentucky) suggest a perimeter spray around affected greens - treat perhaps 20 or 30 feet into the surrounding rough, to kill the cutworms that are attempting to migrate back to the short grass.

Annual bluegrass weevil (a.k.a. Hyperodes weevil) appears to be fairly quiet in most locations right now. The second generation was active in early August in most areas, and a few of those individuals laid eggs for a third generation but most of the insects are beginning to prepare for winter. So larval feeding activity, where it is still occurring, should be slowing down rapidly.

The recent rains have relieved some of the drought stress on lawns. Chinchbugs may still be active, however - if populations are very high, almost any traditional insecticide will reduce numbers quickly. But in most cases treatment should not be necessary - the cooler temperatures are relieving turf stress considerably.

- Submitted by: Dr. Pat Vittum