On warm season turfgrasses primarily bermudagrass ( Cynodon spp.), zoysiagrass ( Zoysia spp.), and increasingly seashore paspalum, billbugs can be a serious pest. There are a several different billbug species that can cause damage but the predominant species is the hunting billbug ( Spehophorus venatus vestitus ). The adults are 13 to 16 mm in length and are normally appear black, but the color may vary from a red-brown to black. Adult females can lay eggs starting in spring and continuing through fall. Once the eggs hatch, the larvae produced are considered the damaging stage. The larvae feed during the summer months. Damage is not normally detected during the summer because the warm season turfgrasses may literally grow out of the damage. Symptoms are most noticeable during the fall and early spring with turf growth has slowed.
Diagnosis is often difficult. Symptoms appear as small circular spots to large blighting of turf. The symptoms appear in color quite similar to what fertilizer burn would look like. If billbug damage is suspected, a good diagnostic key is to tug or pull on discolored plants. If the plants are easily pulled up, it is a good chance that billbug is the problem. Additionally, the sheaths or stems are hollowed out..