Hornet fast facts
Above is a drawing of a hornet's nest (Vespa crabro). Hornets' preferred nesting site is in an old tree, or an existing cavity in a roof space or out building. The nest is similar to a wasp's, i.e. it is constructed of chewed wood mixed with saliva. The wood is obtained from unpainted fence posts, fences, tree trunks, and garden furniture that is unvarnished or treated.
A successful hornet nest has about 200 workers at most, but many have far fewer.
Hornet body lengths are, queens are 29 - 38 mm, workers 22 - 26 mm, and males 29 - 35 mm.
Like bumblebees workers maintain the nest at a steady temperature of around 30oC regardless of the outside temperature.
The hornet lifecycle is similar to that of bumblebees, and the queen will have mated the previous summer/autumn.
Hornet grubs are carnivorous, the adults bring them prey which consists mainly of other insects. They will prey on honeybees. They knock the worker honeybee to the ground, bite off its wings, legs and abdomen, taking only the thorax with the flight muscles back to the nest to feed the grubs. This is chewed up into a paste by the workers and queen and fed to the grubs. As many other prey items are regarded as "pests" by gardeners, it is clear that the hornet should be regarded as the gardener's friend.
Adult hornets prefer sweet foods such as nectar, and as the adults feed the grubs the grubs exude a sweet liquid which the adult lap up. Towards the end of summer when the queen has stopped laying eggs and all the grubs have hatched into adults, there is no more need for the adult hornet to bring back insect prey, and no grubs to give the adults the sweet substances they crave. So the adults go out and search for sweet substances.
Hornets are speedy fliers with a flight speed of 6.0 metres per second and 100 wing beats per second. Compare this with other insects.They are expert fliers and can fly up, down, forwards and backwards.