Billbugs and White Grubsby W.S. Cranshaw and R. Zimmerman 1
(1/09) - Billbugs and white grubs are insects that damage turf
grasses by feeding on the roots. - Heavy infestations of
billbugs and white grubs may kill grass or attract mammals, such
as skunks, that damage grass when feeding on grubs. - Healthy
lawns tolerate injury better than lawns in poor condition. -
Time insecticide applications for when billbug adults are
present. - White grubs are best controlled when a maximum number
of young grubs are present in the upper root zone. Billbugs and
white grubs are serious pests of turfgrass in parts of Colorado.
Both groups of insects feed below ground and damage roots or the
growing crown area of the plant. Infestations also may attract
predators, such as skunks and raccoons, that dig and damage
lawns in search of the insects. |Figure 1: Denver billbug
adult.| Figure 2: Bluebrass billbug adult. Billbugs are a type
of weevil or "snout beetle." Adult weevils can be seen crossing
sidewalks and driveways during