Infestations often damage bluegrass or mixtures of bluegrass and tall fescue. This webworm also attacks bentgrass greens on golf courses, can sometimes be of concern in plantings of pure tall fescue, and has been reported occasionally on bermudagrass. In most instances, bermudagrass develops vigorously enough that serious problems are rare.
Sod webworms are the caterpillars of lawn moths.
They clasp or roll their wings close to their bodies when resting and have mouthparts projecting forward from the head like a snout. The moths are usually noticed when flushed out by a lawn mower or people walking. When disturbed, they fly in a jerky zig zag manner and quickly return to the grass to hide. Around dusk, they may be seen flying a few feet above the grass and dropping their eggs. In a few days, these eggs and others laid on the lower parts of the grass stems hatch into small caterpillars.