Common Name: Baldfaced hornet
Scientific Name: Dolichovespula maculata (Linnaeus)
Description: Baldfaced hornets are large (3/4 inch long) and black with white markings, particularly on the front of the head and the tip of the abdomen. Front wings of hornets and other Vespidae are folded lengthwise when at rest. They construct an inverted, pear-shaped, enclosed paper carton nest which can be up to 3 feet long. The grayish brown nest has two to four horizontally arranged combs and an entrance hole at the bottom. See other Vespidae, i.e., paper wasps, southern yellow jackets.
Life Cycle: Baldfaced hornets are social insects. The mature colony consists of a queen, 200 to 400 winged infertile female workers, brood (eggs, larvae and pupae) and, in late summer, males and reproductive females. Eggs are laid in cells of the nest by the queen. Larvae hatching from eggs are fed by workers. Larvae are legless and maggot-like, and develop through several stages (instars) before pupating. Cells are left open during larval development, but are capped by workers when larvae pupate. Mated female wasps or queens overwinter in protected habitats such as cracks and crevices, and begin a new colony the following spring.
Habitat, Food Source(s), Damage: Mouthparts are for chewing. Nests usually hang in trees, but may be attached to the sides of buildings. Larvae are fed sugary solutions (nectar, honeydew, juices of over-ripe fruits) and insects (flies sometimes caught “on the wing” and caterpillars) collected and brought to the colony by adult foraging worker wasps. Larvae also feed the adults a sweetish secretion from their mouths. Nests are made of “paper”, which is made from chewed weathered wood from old boards, fences or siding by workers. Baldfaced hornet nests are best left alone.
Pest Status: The only “hornet” reported in Texas, it actually belongs to the yellowjacket family (Vespidae). Its sting can be intensely painful.
For additional information, contact your local Texas A&M AgriLife Extension Service agent or search for other state Extension offices.
Literature: McIlveen & Hamman 1991; Metcalfe et al.1962; Swan & Papp 1972.