Like other social wasps, hornets build communal nests by chewing wood to make a papery pulp. Each nest has one queen: she lays eggs and is attended by workers who, while genetically female, cannot lay fertile eggs. Most species make exposed nests in trees and shrubs, but some (like Vespa orientalis) build their nests underground or in other cavities.
Hornets are less aggressive than many more frequently encountered wasp species. In spite of their fearsome reputation, hornets generally only sting in defence of their nest or when something picks them up, and their stings are no more dangerous to humans than a wasp’s. A hornet nest lasts a year. Only the young queens hibernate to survive the winter. Drones die after mating and the workers die off in late autumn.
During late summer hornets, which are just large wasps, become aggressive. This is because the worker wasps’ job is done for the year and they are, literally, waiting to die. After taking care of the queen and feeding the new generation of worker wasps, the old ones are now useless; they become disoriented and venture away from the nest in search of something sweet to eat. There are now a lot of wandering hornets on Wilden Marsh flying just above grass height looking for nectar to sustain them.
This evening I visited a hornets nest in Hoo Wood to see how aggressive they are at the moment; they are not particularly aggressive yet, and it took quite a bit of pushing my 60mm macro lens in their faces before they half-heartedly attacked me.