The European hornet was introduced to the United States in New York, between 1840 and 1860. Since then, it has spread to the other east coast states, across to the Mississippi River, and up into parts of North and South Dakota. Workers are brown with yellow markings and, being hornets, can reach up to one and a half inches in length. They do not look like northern giant hornets, also known as “murder hornets,” which are almost two inches long, making them the largest hornet in the world. While the European hornet is established in the United States, northern giant hornets are not, and were last seen in 2021 in Washington state.
European hornets are mainly large insect predators and do not scavenge for protein. Interestingly, the workers are active at night and are attracted to light, sometimes beating themselves against a nearby window. Nests are defended aggressively, and typically contain 300 to 500 workers - less than yellowjacket colonies. They naturally live in wooded areas in hollow trees, and prefer rural farmland to urban cities. Nests are often found in abandoned wooden structures, but may be built in wall voids and attics, or on the sides of structures. They resemble bald-faced hornet nests, except the paper envelope is tan, not gray, and the nests do not hang freely from branches.
European hornet nests can be treated by applying an insecticide dust or aerosol. First to the nest entrance. Then by inserting the application equipment tip into a side of the nest, if necessary. Staying out of the hornets flight path to and from the nest can help prevent getting stung. Treated nests should be removed from inside structures. Once the brood are no longer cared for, they’ll die and decompose, leaving an unpleasant scent.