Controlling Lawn Insects Bluegrass Billbug Adult billbugs are dull gray to black or brown beetles with a snout or bill.
Symptoms are irregular patches of dead grass, especially near sidewalks or curbs.
The dead grass pulls out easily and has hollow stems. The larvae are present under the grass and brown sawdust-like frass is present in the root zone. The adults can be found in the grass near the dead areas. Larval controls should be applied in June. Use pesticides labeled for use on grubs.