This past week, the Ohio State University Extension office of Wood County received several calls and emails about yards being destroyed overnight.
One caller said it looked like a golf course with holes in the ground with grass flipped up. Other areas looked like when you slice the golf ball and respond by pounding the ground with your golf club leaving holes in the ground. I can relate to that.
No, those yards were not attacked by angry golfers — rather by skunks and raccoons dining on a smorgasbord of grubs in their yard. Most likely the grubs are from Japanese Beetles.
Back in mid-August, Dave Shetlar, emeritus entomologist with the Ohio State University, made a prediction about beetle grubs. Back then, Shetlar gazed into his crystal ball and said, it depends.
He went onto say, remember beetle grubs are the larvae of European Masked Chafers (Amphimallon majale), Northern Masked Chafer (Cyclocephala borealis) and Japanese Beetle (Popillia japonica). All three of these beetles are in the Scarabaeidae family; therefore, they are known as Scarab Beetles. Though the adult Chafers Beetle population is down this year, the Japanese Beetle adults exploded this year across Northwest Ohio.
The life cycle of the Japanese Beetle is considered complete.: egg, grub, pupa, and adult make up the complete life cycle. Most years the adults appear in July. The adults are doing two things, eating and mating, The female has another responsibility – laying eggs in the soil – normally under turfgrass. During August and September, the eggs hatch and the grubs are feeding on the roots of the turfgrass and growing larger. From October through March, they tunnel deep in the soil to overwinter. In April and May the large grubs return to feed again on turfgrass roots. During the month of June, they pupate, and in July are back again as adults.
This past fall though has been warmer and drier than usual. The grubs have enjoyed an extra month of gorging themselves on turfgrass roots.
Raccoons and skunks are also looking for food and calories to gain body fat for overwintering, and your yard with the fat juicy beetle grubs’ smorgasbord is very attractive. Skunks leave the divots and raccoons flip the grass over. The reason your yard smells like skunk is that the raccoons harass the skunks. Nothing like a good food fight.
If you start seeing grub damage, apply products that have the active ingredient Trichlorfon: A common trade name is Dylox. Dylox is available in several formulations and is readily available at most garden centers. It may be necessary to reapply Dylox in April and May if the October application was not effective causing the skunks and the raccoons come back to dine on your yard again.
The most effective treatment for grubs is with preventative turfgrass insecticides applied from June through July. If damage is common each year or if areas of your lawn frequently show grub damage, preventative treatments may be beneficial.
Remember, if you don’t want your beautiful yard to continue to look like a beat-up golf course, treat for the grubs.