1 to 1-1/2 inches in length.
Golden brown with darker brown stripes and markings on its thorax and abdomen.
European hornets are social wasps which form colonies that live for one year. Each spring, an overwintering
queen will find a suitable nesting site and construct a small paper nest. Inside the nest, she builds a small
paper comb in which she raises her first brood of larvae. After these larvae mature into adults, these worker
wasps begin nest enlargement and food foraging for the colony. The paper in the nest and the comb are made from
bits of wood scraped from logs, bark, and even the wood on decks and houses. Like bald-faced hornets and yellow
jackets, European hornets aggressively defend their colony if it is disturbed. Loud vibrating noises, such as
those from lawnmowers and leaf blowers, can "set off" the hornet workers causing them to sting people and pets.
The colonies of European hornets may contain several hundred workers by the end of the season.
The European hornet, Vespa crabro (Linnaeus), gets its name from the fact that it was brought to
the United States from Europe. It first came to New York around 1850. It has spread west to the Dakotas
and south to Louisiana. It has other names, including Giant hornet and Brown hornet.
The European hornet is a large insect. The adults range in size between ¾” and 1 ⅜” in length. They are
brown with yellow stripes on the abdomen and a pale face. The workers can sting but they are not particularly
aggressive around the nest.
The European hornet is a social insect. This means that it lives in a colony. The colony starts in the
spring with a fertilized queen that spent the winter hibernating. She finds a place to build a nest. She uses
chewed up cellulose from decayed wood to make the nest. The usual nest sites are holes in trees, but these
insects also make nests in attics or wall voids of homes and occasionally in the ground. Sometimes the
nests are exposed on the sides of buildings.
At first, the nest only has a few cells. The queen lays an egg in each cell. When the eggs hatch, the queen
feeds the larvae nectar and insects. When the larvae have developed into adults, they take over the work. The
workers are sterile female insects. The queen’s job is to produce eggs. Through the summer, the number of
workers grows. They expand the nest and bring food for the larvae.
European hornets feed on large insects, such as grasshoppers, yellow jackets, and bees. Because of this,
most people consider them to be beneficial. They also gather sap from plants. The workers are active at night.
They are attracted to lights and they sometimes startle homeowners by flying into windows where lights are
In late summer, male hornets and fertile females begin to hatch. The males mate with the fertile females.
These will be the queens for the following spring. The fertilized females seek a hiding place to spend the
winter. The males and the workers die as winter approaches.
Controlling European hornets starts with an evening inspection. Since the workers are active at night,
nighttime is the best time to watch them to learn where their nest is located.
The location of the nest will determine the best method for control. If the nest is in a void – inside a
wall or in a hole in the ground, a dust insecticide might be the best choice. If the nest is exposed on the
side of a building, an aerosol insecticide might be the best choice.
Hornet nests are often difficult to reach and to treat. Because of safety concerns, it is advisable to call
pest control professionals to treat hornet nests. They will have the equipment and the products that are
necessary to control hornets effectively.
Like bald-faced hornets, this hornet constructs aerial paper nests usually in trees and large shrubs. European
hornets, however, will also nest inside the voids of buildings, usually in an attic or chimney. Nests may also be
constructed on the sides of buildings.
Hornets and yellow jackets should only be controlled by an experienced professional. The danger of stings is
considerable. Proper protective clothing and equipment are required.