We are experiencing an infestation of Hunting Billbugs in West Tennessee. An adult billbug is a 1/5" to 3/4" long beetle that lays its larvae in the stems of your grass blades. They predominately feed on Bermuda and Zoysia grasses.
To find out if your lawn has billbugs look for "dead" spots in your lawn. If you find one, simply pull the grass back to see if the roots are still in place or dig down a bit to see if you can spot the bug itself. Billbugs cause damage by laying their larvae and after they hatch by eating the root of your grass. The adult Billbug will eat the grass on top. So, you may not immediately see any damage. In fact, the damage may not even show up until Spring when the grass tries to come out of dormancy.