Sod Webworms

In their caterpillar stages, sod webworms (Crambus species) are serious pests of lawn grasses. The caterpillars are about 3/4 to 1 inch long. They have dark shiny brown heads, but their color varies from greenish to beige, brown or gray, depending on the species. They have 4 parallel rows of distinctive dark spots along the length of their abdomen. Long, stiff hairs protrude from these spots. The adults are buff-colored or grayish-brown moths with a wingspan of about an inch. They fly in the early morning or late evening in a jerky zigzag pattern, just a few feet above the lawn, which explains another common name for these pests, “lawn moths.” They fly up from their hiding places when tall grass is mowed or shrubbery is disturbed. They are also attracted to lights at night.