Sod Webworms Description:
Sod webworms are grayish-green caterpillars with dark brown heads and brown spots along the length of their bodies. The caterpillars live in silken tunnels at the base of grass blades, feeding on the grass blades at night and hiding in their tunnels during the day. Some species do not construct silken tunnels, but also live in the thatch layer.
Common grasses subject to sod webworm infestation include:
- Kentucky bluegrass
- Perennial ryegrass
- Fine fescue
Warm-season grasses such as bermudagrass and zoysiagrass are rarely affected, however, a tropical sod webworm may invade St. Augustinegrass.
Biology & Symptoms:
Small, brown areas appear as scalped turf enlarge as sod webworms continue to feed. An easy indicator is the presence of small moths flying just above the grass in the early evening hours or that flush out during mowing. Small green pellets (frass) may also be seen at the base of grass blades. Spring and summer are the common feeding seasons
Early detection is key by looking for close areas that appear scalped and caterpillars in silken tunnels. Insecticide treatments and fertilization are the most effective treatments. Schedule a consultation with your local landscape professional to learn more about the best practices to rid your lawn of sod webworms.