Hornet

True hornets belong to the genus Vespa within the wasp family Vespidae, and are the largest of the social vespid wasps, with the European Hornet being the best-known representative in much of the Northern Hemisphere and one of the few true hornets established in North America. They are often confused with other large wasps, but true hornets form a distinct genus recognized by size and specific coloring.

Hornets are notable for their large, enclosed, multi-layered paper nests, often built inside hollow trees, wall cavities, or other sheltered spaces, distinguishing them from the more exposed open-combed nests of many paper wasps. Their size and loud flight sound also make them one of the more conspicuous social insects encountered outdoors.

Ecologically, hornets are effective predators of other insects, including flies, caterpillars, and yellowjackets, helping regulate populations of smaller insects, while adults also take tree sap and ripe fruit as food sources.

• Large, robust body noticeably bigger than a yellowjacket, with a reddish-brown thorax and head contrasting with a yellow-and-black striped abdomen.
• Wings are amber-tinted and folded along the body at rest.
• Head is broad with large eyes and a distinct notch or curved margin near the eye, useful for identification against similar wasps.
• Lookalikes include large yellowjackets and hornet-mimicking robber flies, but true hornets are distinguished by their larger size and reddish-brown coloring on the thorax.

European Hornets are native across much of Europe and temperate Asia and have become established in parts of the eastern United States. They favor wooded areas, nesting inside hollow trees, sheds, wall voids, or other enclosed cavities, and are active from spring through fall, often more active at dusk and after dark than many other wasps.

Hornets are active predators, capturing flies, caterpillars, and other wasps to feed developing larvae, while adults themselves feed on tree sap, ripe fruit, and other sugary sources. Colonies function cooperatively, with workers defending the nest and cooperating in foraging and brood care, and hornets are known for their audible buzzing flight and tendency to fly toward lights at night. Their predation on pest insects gives them a beneficial ecological role in the areas where they occur.

A single overwintered queen founds a nest in spring, initially building and provisioning it alone before her first worker offspring mature and take over colony tasks. The colony grows through summer as workers expand the enclosed paper nest in layers, and toward late summer or early fall the colony produces new queens and males for mating. After mating, only the new queens survive to overwinter in sheltered spots such as under bark or in leaf litter, while the rest of the colony dies off with cold weather, completing one generation per year.