European Chafer Damage
The larvae of European Chafer (white grubs) start feeding on turf roots in April and then again in September. Damaged turf starts to turn brown and thin out. Skunks and raccoons may start digging up your lawn to eat the grubs. European chafer grubs feed on your lawn September thru November and then start up again in March. When you get to about 5 grubs per square foot you will start to see damage. The adults do not feed on the foliage of trees and shrubs European Chafer adults emerge in late June and July (about two weeks earlier than the Japanese Beetle). Their life cycle is similar to that of the Japanese beetle. The adults emerge at dusk and congregate in trees to mate. They return to the turf around midnight to lay eggs and hide until the next evening. It is very easy to completely miss the presense of the adults since most of their activity is after dark.
How To Identify European Chafer
The larvae of the European chafer is White C-shaped and about .5 to .1 inches long by late September. European Chafer adults are a light brown, stout bodied, have a clubbed atennae and are .5 inches long.
How to get rid of European Chafer
There are two ways to control the European Chafer. First, you can use curative products. This includes carbaryl and triclorfon and must be watered into your grass immediately. If you use this too late in the fall, it will not work because the grubs will not be feeding so they will not be hit with the insecticide.
The second way to control the European Chafer is using preventative insecticides like imidacloprid, thiamethoxam, clothianidin, and anthranilic diamide. This will not kill the grubs that are present but will kill the grubs that have not developed yet. Applications should be made between June 1 amd mid July and this application must be watered into the lawn with at least .5 inches of water.