Vespula spp., Vespa spp., Polistes spp.

Range: Throughout the United States

Habitat: Yellowjackets are encountered around homes and buildings. Nests are often located underground in an old rodent burrow, beneath a landscape timber or in a rock wall or wall of a building. Hornet nests resemble a large, inverted teardropshaped ball, which typically is attached to a tree, bush or side of a building. Hornet nests may contain thousands of wasps that are extremely aggressive when disturbed. Paper wasps typically build their umbrella-shaped nests under eaves and ledges. These wasps are not as aggressive as yellowjackets or hornets.

Health risks: Hundreds (perhaps thousands) of people in the United States die each year from allergic reactions to the venom of these insects. They are more dangerous and unpredictable than honeybees and should be treated with respect; nests should be eliminated with great care and in a specific manner.

Management: If the nest can be located, it can usually be eliminated by carefully applying spray insecticide into the nest opening. Hornet nests have a single opening, usually toward the bottom, where the wasps enter and exit. It is essential that the paper envelope of the nest not be broken open during treatment, or the irritated wasps will scatter in all directions, causing even greater problems. Paper wasps can be eliminated rather easily with an insecticide spray. Control measures should be taken at night for all wasps.