Social wasps, as their name suggests, live in colonies. The make-up of these colonies is similar to that of other social Hymenoptera (ants, honeybees), with a dominant reproductive queen, reproductive males (drones) and non-reproductive worker females. The workers spend much of their time foraging, and wasps are important predators of insect pests such as caterpillars and other small soft-bodied insects. The insects are fed to the wasp larvae, and in return the larvae exude a sweet substance to feed the workers. In autumn, when the queen stops producing eggs, the workers no longer have their food, forcing them to search for replacement sources of sugar. Normally, this would be found on rotting fruit, but the abundance of sweet human foods such as jam encourages them to invite themselves to our tables. This explains why wasps are generally only a nuisance in the autumn.
In contrast to honeybees, wasps are not killed once they sting. Honeybees have barbs on their stings, which prevent the bees from removing the sting from the perceived threat. Wasp stings are barbless, so they can be withdrawn and used again.
The cuckoo wasp, Vespula austriaca lays her eggs in the nests of a related species, the red wasp, Vespula rufa.
The hornet, Vespa crabro, is the largest British wasp. If your garden has old trees, which hornets use to nest, then you may see these rare insects. Be careful as they can be aggressive.