There is an anchor—shaped black mark on this yellowjacket’s first abdominal segment. The first antennal segment is black.
Nests usually are subterranean. In urban environments, nests are in the walls of houses and other buildings. Colonies usually have peak numbers of workers in August or September. Nests contain 2,000 to 5,000 workers.
Habits. This species often builds nests underground around the perimeter of houses and commercial buildings. The opening to the nest may be hidden among flowers, often in a shaded location or protected from rainfall.
In these sites, a nest may be disturbed accidentally and the wasps become aggressive. Colonies contain a large number of workers in fall, and they remain active until the first or second frost.