Sod Webworms
Caterpillar larvae that feed on grass blades at night and hide in silk-lined tunnels at the soil surface during the day. Damage appears as irregular brown patches with ragged, closely clipped grass. Adult moths (buff-colored, with a snout) fly in a zig-zag pattern over the lawn at dusk.
Sod webworms are the larvae of several lawn moth species. They clip grass blades at or near the soil surface and drag them into their silk tunnels to eat. Damage is most common in summer during hot, dry periods.
Identification: Look for small, tan moths flying in a bouncy zig-zag pattern over the lawn at dusk. Small green/brown droppings (frass) at the soil surface. Irregular brown patches with closely cropped-looking grass.
Soap flush test: Same as for mole crickets — dish soap solution will bring larvae to the surface.
Control: Bifenthrin or permethrin applied in the evening when larvae are feeding. Bacillus thuringiensis (Bt) is an effective organic option.
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