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 acts as a selective pressure on the workers, so they are more likely to exercise reproductive restraint. It has been suggested that workers in reproductive nests may kill their queen so they can reproduce. When researchers at the University of Sheffield examined a collection of nineteen "D. maculata" nests during the reproductive phase of their life cycle, they found that 14/19 nests did not have a queen. Matricide might occur after sufficient workers have been raised and queen-destined eggs have been laid. However, matricide has not been directly observed and other causes of death are possible. Diet in "D. maculata"