Bald-faced hornet Bald-faced hornet Dolichovespula maculata is a eusocial wasp of the cosmopolitan family Vespidae. Its colloquial names include the bald-faced hornet, bald hornet, white-faced hornet, white-tailed hornet, spruce wasp, blackjacket, and bull wasp. This species is a yellowjacket wasp, not a true hornet (genus "Vespa"). Colonies contain 400 to 700 workers, the largest recorded colony size in its genus, "Dolichovespula". It builds a characteristic large hanging paper nest up to 58 centimetres (23 in) in length. Workers aggressively defend their nest by repeatedly stinging invaders. "Dolichovespula maculata" is distributed throughout the United States and southern Canada, but is most common in
Bald-faced hornet the southeastern United States. Males in this species are haploid and females are diploid. Worker females can therefore lay eggs which develop into males. Matricide might occur after sufficient workers have been raised and queen-destined eggs have been laid, in order to give workers a reproductive advantage. The bald-faced hornet gets its name from the characteristic white markings on its face, as the word "bald" in English is derived from the word piebald. It was first described by Linnaeus in 1763. "D. maculata" is part of the cosmopolitan family Vespidae. It is in the genus "Dolichovespula". Its black and white