The white grubs that routinely damage lawns in Iowa are called annual white grubs. These root-eating, underground June beetle larvae have one generation per year and take one year to complete their life cycle of egg, larva, pupa and adult. The adult beetles of our annual white grubs are specific kinds of June beetles called masked chafers. They are tan or straw brown in color and as the name implies, they have a black stripe across the eyes and face. The masked chafers begin flying in late June and lay eggs in the turf during July.