Hornets:  Facts, Identification & Control

Hornets belong to Kingdom Animalia, Phylum Arthropoda, Class Insecta and Order Hymenoptera, Family Vespidae. There are only about 20 species of true hornets in the world. The only specie of true hornet in the U.S. is the European hornet (Vespa crabro). As its common name suggests, the European hornet is an introduced species that came to the U.S. from Europe and has adapted to many regions of North America. The European hornet is yellow and brown in color and measures about 1 1/2 inches long.

While not a true hornet, the baldfaced hornet (Dolichovespula maculata) is included here since most people typically think of it as a hornet. The baldfaced hornet is about an inch long and is colored black and white. The behavior and habits of both the European hornet and the baldfaced hornet are very similar to yellow jackets, which are actually wasps. Size is the most easily recognized difference since yellow jackets are smaller than hornets.

Baldfaced hornets make aerial nests, circular in shape, about the size of a football or basketball and usually built in trees. European hornets tend to make their nests in secluded, aboveground locations like hollow trees, attics, porches and inside wall voids. Hornet nests are constructed with paper-like construction material produced by the hornets mixing their saliva together with wood they gather. During the nest-building time of year, it may not be unusual to see a hornet scraping away a thin layer of wood from a wooden fence, an old log or the side of an unpainted wooden building.

While hornets are known for their ability to inflict a painful sting, they are very beneficial predators and help to control a variety of insects that could otherwise become pests. However, hornets are social insects, so they will aggressively defend their colony (nest) from any intruders. While not as aggressive as yellow jackets, the baldfaced hornet, and to a lesser degree, the European hornet, quickly and assertively defend their nest when sensing danger.

It is always best to seek the advice and assistance of your pest management professional before attempting any do-it-yourself efforts for hornet control.

How Orkin Treats for Hornets
Most people use the common name hornet to designate both the baldfaced hornet and the European hornet, even though the European is a true hornet and the baldfaced hornet is actually in the same stinging insect group as yellow jackets. Therefore, when describing the treatment of hornets, the first requirement is for your pest management professional to provide an inspection and determine the identity of the stinging insects requiring control and the location of their nesting sites. Once the inspection and identification is complete, your pest management professional can develop a specific treatment plan that involves effective treatment measures, whether preventive, non-chemical or chemical treatment procedures. Some components of the hornet treatment plan may include:

  • Educating homeowners on the predatory benefits of hornets as they prey on and reduce the numbers of many damaging insects. Also, the pest management professional will explain that removing nests once the hornets are eliminated is important since other insects may infest old nesting material that is allowed to remain on the property or inside the structures.
  • Explaining why effective hornet treatment involves treating the nest, an explanation of where hornet nest(s) were found and how those nests will be managed is very important. Nest location is one of the differentiators between European hornets and baldfaced hornets. European hornets usually nest in wall voids or in the open portions of attics, while baldfaced hornets usually construct aerial nests in trees or large bushes.
  • Explaining the importance of using exclusion materials to prevent other hornets from entering wall voids or attic spaces and building new nests.
  • Recommending keeping trees and landscape bushes well trimmed, thinned and open so hornets are discouraged from building their aerial nests. In general, baldfaced hornets prefer to build their aerial nests in hidden, protected portions of trees and bushes.
  • Explaining what products and equipment will be used. Your pest management professional may employ ready-to-use aerosol sprays, liquid sprays from power equipment or an insecticide dust. These products are applied into the nest entrance and will help control hornets that are entering and exiting the nest. If the nest is located close to areas where people frequent, it is best to do the control work after dark when hornets are almost all inside the nest. Complete control may require more than one treatment visit to ensure all nest occupants are eliminated.
  • If the nest population is small and in an exposed, easy to access location, removing the nest without using insecticides may be possible. While nest removal is possible, it is best done at night and will involve using a heavy plastic bag to cover the nest and seal it shut. The nest can then be removed and disposed. Remember, since hornets are aggressive and will furiously defend their nest, nest removal should be done while dressed in a fully protective bee suit and faced protecting veil. You may want to contact your pest control professional.

Hornet Stings

Bald-Faced Hornets

The bald-faced hornet belongs to the Genus Vespula. Bald-faced hornets are more closely related to yellow jackets than they are to hornets.

Hornet Nest

Hornet nests are composed of a paper substance derived from saliva and wood pulp. They are located within or atop trees, in attic rafters and in other covered areas.

Giant Hornets

The Vespa Crabro is also known as the European or giant hornet. The giant hornet closely resembles the bald-faced hornet.

What do Hornets Eat?

Hornets are predaceous and feed primarily on other insects. Controlled populations of hornets can assist in pest control, although a nest located near or inside a home may prove extremely dangerous to humans.

Bees and Hornets

Bees are flying insects that feed on pollen and nectar. They have segmented bodies, two pairs of wings and antennae. Of these species, the Western honeybee is most revered.

Getting Rid of Hornets

Pest control professionals should be consulted before attempting to treat any hornet infestation. Hornets are typically aggressive, and some individuals may be allergic to their sting.

European Hornets

This hornet was brought to the U.S. from Europe and is a large brown insect with yellow stripes and a pale face. European hornets eat grasshoppers, yellow jackets and bees.