The air is filled with the buzz of cicadas right now in South Carolina, and they’re gradually heading north over the summer months. In large populations, these noisy insects can injure the decorative and fruit trees in your landscape. Damage occurs when female cicadas slice open small-diameter branches to lay their eggs, often peeling the bark and girdling the branch. For mature trees, cicada damage—aka flagging— is often cosmetic, but for younger trees and smaller plants it may be fatal. Fortunately, nature provides several efficient cicada predators, including birds, mammals and insects like the cicada killer wasp, that can help to lower the population.
Reaching nearly 2 inches in length, cicada killers are some of the largest native wasps in the United States with several related species spread across the Americas. As the name suggests, the female wasps hunt cicadas as a source of food for their larva. (The adult wasps feed on nectar.) Female wasps paralyze cicadas with their stingers, then take them to an underground nest, easily recognizable by a large hole in the ground with a U-shaped pile of earth in front from the excavation process. Once in the nest, a female wasp lays an egg on the living cicada, which the larva will feed on when they hatch several days later. Throughout the course of the summer, a single female wasp can eliminate well over a hundred cicadas, which can be very helpful for gardeners and homeowners alike.
While cicada killer wasps might look dangerous, entomologists refer to them as gentle giants because they pose very little danger to humans. These helpful insects often get a bad rap based on their large size and classic hornet appearance. In reality, only the female cicada killer can sting you, as the males, which are smaller, don’t have a stinger. However, it’s still rare for the female to sting, as they aren’t aggressive.
For families with small children, discourage cicada killers from excavating burrows in areas that your kids frequent. Wasps prefer a sunny spots with bare ground to excavated their burrows and can be discouraged by mulching bare patches of ground, ensuring thick grass or vegetation grows in the yard, or by regularly watering any potential nesting sites.