Strawberry leaves attacked by strawberry rootworm beetles are riddled with small holes. Some leaf damage occurs in May, but most occurs in August. Heavy infestations can reduce plant growth or kill plants. Although adults of the strawberry rootworm feed on the leaves of strawberry, root-feeding by the larvae is more damaging to strawberry production. Adult strawberry rootworms overwinter in mulch and soil crevices, and become active in May and June.
Adults feed primarily at night and hide in soil or mulch during the day.
They chew small holes in leaves, and females lay eggs on older leaves near the soil surface. Larvae burrow into the ground to feed on strawberry roots from late spring to early summer. New adults begin emerging in mid-summer, and these beetles feed on strawberry foliage through early fall. Scouting for the presence of adult beetles is best done after dark using a flashlight to examine plants. No threshold has been established for this insect, but a population of 10 to 20 beetles per square foot is considered high.