Facts, Identification & Control
Ground wasps include a huge number of different species, so their physical appearance differs greatly. Two easily recognized characteristics of ground wasps is the presence of two pairs of wings and a constriction between the wasp’s thorax and abdomen – a trait known as “thread-waisted.”
Behavior, Diet and Habits
The common name ground wasp comes from the behavioral trait of usually constructing their nest underground. The ground wasps most frequently encountered are yellow jackets, cicada killer wasps and digger wasps. Yellow jackets usually construct below-ground nests; however, sometimes they choose to nest above ground in sheltered, dark locations such as crawl spaces, wall voids, fallen trees and thick bushy vegetation.
Ground wasps are grouped as either social or solitary, depending on their behavior. Social ground wasps are communal insects that live in nests populated by egg laying queens, male adults and the immature egg, larval and pupal stages. The numbers of adult wasps in the nest will usually number more than 500. The nest is maintained and fed by sterile female worker adults who gather prey to feed the immature stages. A social ground wasp colony lasts only one year and is aggressively defended by adults who are very likely to inflict numerous stings on intruders. Yellow jackets are an example of social ground wasps.
While the social ground wasps usually demand our attention since they present the greatest stinging hazards, the solitary ground wasps, such as cicada killer wasps, spider wasps and digger wasps make up the vast majority of ground wasp species in the U.S. As the common name suggests, each adult female solitary ground wasp builds a below-ground nest (not all species do this) and hunts for prey that she feeds her offspring all on her own. Solitary ground wasp females use their stinging mechanism to paralyze prey. While some solitary ground wasps can sting, they rarely do so when left alone.
In most situations, the best way to manage ground wasp populations is to simply leave them alone and let them continue helping us by hunting and preying on damaging insect pests. This beneficial association is especially valued with the solitary ground wasps. However, ground wasps, especially social ground wasps like yellow jackets, become a problem if the nest is close to areas frequented by people or pets. The first thing to do when considering control is to contact your pest management professional (PMP). They will identify the wasp, make recommendations and advise you on whether to attempt do-it-yourself control options. If you choose to leave it to the PMP, they will ensure the ground wasp problem is resolved in a safe and effective manner.