Hunting Billbugs
Egg -- The elongate, creamy white eggs are 2 to 3 mm long and turn yellow before hatching.
Larva -- The white, legless grubs have hard, yellowish- or reddish-brown heads. When mature, these larvae vary from 9 to 16 mm in length.
Pupa --The pale yellow or white pupae are similar to adults in size and shape.
Host Plants -- Most species of grasses are subject to billbug infestation. However, hunting billbugs prefer zoysia and Bermuda grasses.
Damage -- Both larvae and adults injure turf grasses. The larvae are root feeders; the beetles eat leaves and burrow in stems near the surface of the soil. Variously shaped, yellow or brown patches appear in infested lawns. The symptoms may resemble fertilizer burn. However, in the case of billbug infested lawns, tufts of discolored grass can be easily pulled up (unlike grass burned by fertilizer).
Life History -- In the southern states, billbugs may overwinter in any life stage, although adults are best able to withstand severe winters. Emerging in the spring, adults feed and mate. Females place eggs in cells cut into grass stems. Two days to two weeks later, larvae appear and work their way down from the inner leaves to the root system. They feed for 3 to 5 weeks before pupating in cells in the soil. The pupal period lasts 3 to 7 days. Afterwards, the new adults may remain in the pupal cells to overwinter or may emerge and be active until the onset of cold weather. One generation is completed each year.