Billbugs or Drought?

This season continues to catch the BugDoc off guard! Shortly after I sent out the last P.E.S.T. newsletter, I got an “emergency” call from our Diagnostic Clinic that a golf course superintendent in South Dayton had detected considerable damage on his fairways and around some of his greens due to a “strange” little white grub. I was thinking of the black turfgrass ataenius as it would be time for their larvae to be causing damage, especially in the Dayton area.

The next day a plastic water bottle arrived by courier with a half dozen, nearly mature, billbug larvae…still squirming. Good grief! I don’t normally think about seeing billbug damage until the end of June and first week of July.

Again, I had to recalibrate my brain for this season. I called the superintendent and found out that they had already applied Dylox. When turf is being lost, golf course superintendents don’t fool around.  Anyway, I confirmed that Dylox would be one of the curative treatments to control billbug larvae. However, if the treatment didn’t kill the larvae in two to three days, they may want to consider using a product that contains clothianidin (Arena or Aloft) or dinotefuran (Zylam). These are the fast acting of the neonicotinoids and our field studies have shown that both insecticides have pretty good billbug curative action.

Just because this was found on a golf course, don’t forget that billbugs do major damage to home lawns and commercial grounds, especially when we have early dry periods. I have been checking around campus and about half of the turf that is turning straw color is from drought stress, but the other turf is obviously being hit by billbugs. Remember that the test for this critter is to do the “tug test.” Simply grab some of the stems that are turning straw colored and tug. If they break easily and you see fine, sawdust-like material in the broken stem, you have billbugs!

Author: Dr. Dave Shetlar