Cicada killer wasps are large, intimidating insects that can frighten children and adults alike. While they are not considered dangerous, cicada killers can be an annoyance whose burrows can disfigure a lawn. These are solitary wasps that do not build communal nests. They do, however, live in groups where each adult female builds its own nest. If you have cicada killer wasps burrowing in your yard and want to get rid of them, there are several steps you can take.
Start your lookout for nesting cicada killers in mid-July. Treating the burrows early in the wasps' breeding season is important in preventing an infestation in the following year. The longer you wait, the more the chances that cicada larvae will survive in walled-off protected cells in the burrows, to mature and emerge in the following July.
As a solitary wasp, each female cicada killer builds its own nest, a burrow with a single entrance and several tunnels that may have 16 or more cells in which its larvae feed on paralyzed cicadas. While the wasps are solitary, they live in nesting aggregations that may contain from a handful to 100 individual burrows. These are often built in bare patches in lawns or in piles of dirt where there is plenty of sun.
Mark the locations of the wasps' nests so that you can find them at night. Push a stake or stick into the ground near the entrance to each burrow. Be careful not to push the stakes into the nests themselves.
Treat wasp nests at night, when all the wasps are in residence and settled for the night. Don gloves and a long-sleeved shirt to protect yourself from any possible retaliation and from getting pesticide on bare skin. Mix and prepare your pesticide liquid or dust. Carbaryl-based pesticides are particularly effective against cicada killers.
Sprinkle or spray the pesticide directly into the nest. Sprinkle or spray only a small amount of pesticide into each nest; it won't take much of the poison to kill the inhabitants. Leave the pesticide in place to do its work. Don't block the tunnel entrance; you want the female to walk through the poison.
Repeat the treatment several times during the breeding season (mid-July to mid-September). Kept an eye out for new burrows.