Are you seeing Japanese beetles on your property?
They emerge in late June in southern Illinois and early July in central and northern Illinois. They are 1/2 inch long, heavy-bodied, oval beetles that are metallic green with coppery wing covers. U of I Extension Program Coordinator Sarah Ruth says there are both nonchemical and insecticide options for managing Japanese beetle adults and grubs, but timing is important.
Japanese beetles feed on wide range of plants, preferring smartweed, grape, raspberry, rose, crabapple, linden, and willow. The grubs feed on the roots of grasses, vegetables, and ornamental plants.