Identification
Large, brown with yellow marks. Compare
Cicada Killer, an unrelated Sphecid wasp of similar size.
Range
Eurasia, subspecies germana introduced to eastern North America.
Food
Predatory on other insects, used to feed young. Also girdle twigs to drink sap.
Life Cycle
Paper nest is built in hollow trees, or in human structures such as attics. Adults come to lights at night, perhaps seeking prey?
Queens emerge from hibernation during the spring, and they search for a suitable location in which to start a new nest. They build the nest with chewed wood pulp, and a few eggs are laid in individual paper cells; these eggs develop into non-reproductive workers. When 5-10 workers have emerged, they take over the care of the nest, and the rest of queen’s life is devoted solely to egg laying. The workers capture insects, bringing them back to the nest to feed the brood. Workers need more high-energy sugary foods such as sap and nectar, and hornet larvae are able to exude a sugary liquid which the workers can feed on.
The nest reaches its peak size towards mid September. At this time the queen lays eggs that develop into males (drones) and new queens, she then dies shortly after. The new queens and males mate during a 'nuptial flight', after which the males die, and the newly mated queens seek out suitable places in which to hibernate; the old nest is never re-used.
Print References
Swan and Papp, p. 543, color plate 7m
(2)Internet References
Vespa Crabro. Translated from German.
