The cicada killer wasp is the largest wasp found in Iowa. Cicada killer wasps may be up to 1.5 inches long. They are black with yellow markings on the thorax and abdomen, and they have orange-colored translucent wings.
The cicada killer wasp is a native species found throughout the eastern two-thirds of the U.S. In Iowa, they are common and frequently abundant every summer from early July to mid-August.
The cicada killers are solitary wasps; that is, they do not make a social colony with a queen, workers, and drones like honey bees and yellowjackets. Instead, they live independently without help from other members of a colony to share in the raising of young or the maintaining of a nest.
Each female cicada killer wasp works alone to dig and provision a nest for her offspring. Nest tunnels extending up to 24 inches deep are dug into the ground. Nests holes about the size of a quarter typically occur at the edges of flower beds or along sidewalks and driveways. The female flies to nearby trees, where she captures annual cicadas and places them in cells located at the ends of the tunnel. One or two paralyzed cicadas are placed in each cell, and a single egg deposited before the cell is closed by the female, who flies away, never to return. The wasp larvae feed on the cicadas and develop into wasps that emerge the following summer.
Solitary wasps such as the cicada killer are unlikely to sting and are generally not a threat. The female wasp can sting, but won't unless handled or threatened. They are not dangerous despite their large size. Stings inflicted by solitary wasps are usually not severe, but reaction varies with each individual.
Males cannot sting but are known for their territory-protection behavior of "patrolling" along sidewalks and driveways and "dive-bombing" at people, pets, and any other large insect that enters their territory.
The cicada killer wasp attacks annual cicadas – it is not a threat to honey bees, bumble bees, or other insects.
Wasps are generally beneficial, and a nest in an out of the way location where it is not likely to be disturbed should be left alone. Cicada killer wasps are a temporary annoyance; we believe cicada killer wasps can be safely tolerated most of the time. If, however, a nest is located where problems could arise, such as near the mailbox or a frequently used door, removal may be justified.
The practical control for cicada killer wasps is to apply an insecticide dust or wasp & hornet aerosol foam into the nest opening at night. Cover the nest opening with a shovelful of soil after all activity has stopped. For more information on insecticides, please see this article.
Do you live in Iowa and have an insect you would like identified?
The Iowa State University Plant & Insect Diagnostic Clinic will identify your insect, provide information on what it eats, life cycle, and if it is a pest the best ways to manage them. Please see our website for current forms, fees, and instructions on preserving and mailing insects.
Contact information for each states diagnostic laboratory for U.S. residents. If you live outside of Iowa please do not submit a sample without contacting the Plant & Insect Diagnostic Clinic.