Source(s): Jason Vance, Gwinnett County Extension Intern, Biology Major, Georgia Southern University.
Every summer we often hear about sightings of an abnormally large wasp or bee buzzing around the lawn. This intimidating insect can measure from 1½ to 2 inches in length and is black or brown with colorful yellow markings on the abdomen and a stinger measuring ¼ inch long. There is not much need to worry for this is neither a mutated nor an invasive insect, but is rather a native species of wasp commonly known as the cicada killer.
Sightings are common from mid to late summer as the adults are emerging or searching for cicadas. After emerging the adult wasps will feed on flower nectar, mate, and dig burrows preparing for the next generation. Once it is ready to reproduce, the adult female will capture a cicada, sting it, which paralyzes it, then carries it to a previously dug burrow measuring 10 inches to 4 feet in length. The wasp will then lay a single egg, bring in the paralyzed cicada, and then seal the chamber. The egg hatches and begins to eat the insides of the still-living cicada for 4- 10 days. Once everything but the outer shell has been devoured, the wasp larva then spins a silken case and prepares to overwinter. Come springtime, the larva begins to pupate becoming adults. The next generation of adults will crawl out of the ground and start the process over again. Only one generation occurs each year.
As frightening as these insects may appear, they are typically not aggressive and are actually considered to be beneficial. These wasps will not sting unless cornered or accidentally touched or stepped on. In this case, a cicada killer’s sting can be very painful. The sting is not dangerous unless the victim is known to be allergic to bee stings or shows signs of an allergic reaction. If this occurs, it would be wise to seek medical attention. The only places this insect can pose a real threat are where people, especially children, tend to congregate or play. If one gets to close to a burrow, one may encounter an inquisitive male guarding the area. There is no real need to worry, for he is only bluffing and possesses no stinger.
Though this insect is solitary, it is possible to find groups of wasps in certain areas. A single burrow may be no real problem, but an infestation can become unsightly and possibly even smother turfgrass. This is, however, quite rare for they prefer to nest in sandy, well-drained soil exposed to full sunlight.
If cicada killers prove to pose a threat to ones safety or the appearance of your lawn, there are many ways of prevention and control. One may use cultural practices to prevent establishment of a cicada killer colony by maintaining a healthy lawn by fertilizing and frequent watering. This promotes thick growth of turfgrass, creating an undesirable place for cicada killers to nest. One may also apply ground covering and mulch on lawns and recreational areas to deter the wasps from nesting in the area.
Though rare, if an infestation becomes out of control, a safety risk, or a liability, one may use insecticides to control the problem. Appropriately labeled insecticides may be used to kill adult wasps or treat nesting areas. Call your local Extension office or click below on “Georgia Pest Management Handbook” for a list of up-to-date approved chemicals for treatment. Always follow the instructions on the product label.
Most importantly, remember these insects are beneficial. If they pose no threat, leave them alone as they aid in keeping populations of certain insects in check.
Center Publication Number: 209