Sod Webworms Sod webworms, Crambus spp. Bent and blue grasses most susceptible to injury, especially new lawns. Larvae feed on grass blades, growing tips, and greener portions of crown, but not on the roots.
Damaged areas appear as scattered irregular, brown patches in turf.
Moths hide during day in grass and shrubbery, fly over grass at dusk. Eggs are laid on the leaves and crown. Larvae hatch in a few days and begin to feed. They feed at night and hide during the day in shelters constructed of bits of grass and debris. Moths begin flying in April or May in warm areas and breeding continues through October.