Hornets and wasps are some of the most common, and often most feared, insects. However, these monikers are not sufficient to describe the thousands of species--some 4,000 in the United States alone--that people encounter all over the world. Overall, wasps have long, thin bodies and are known for having the most painful sting of all varieties of bees. Hornets are known for their aggression and their large, hanging nests.

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Several types of wasps and hornets commonly occur near people.

Bald-Faced Hornets

The Bald-Faced Hornet is named for the white patches on its face. Other than this, the body is black and about three-fourths-inch long. This species of hornet occurs all over the United States. The bald-faced hornet feeds primarily on nectar and fruit juices. They build hanging nests from anything--trees or buildings. All the nests start with a single queen that begins the nest in the spring. This species of hornet is very aggressive. Individual insects are able to sting over and over again because their stingers are smooth, so do not get stuck in the person or animal they sting. Humans can have an allergic reaction to the venom of bald-faced hornets.

European Hornets

European hornets are large, measuring about 1 1/2-inches long. Other unusual traits of European hornets include flying at night and hunting in groups. European hornet colonies are made up of queens, which lay all the eggs and reproduce, female workers that build the nests and male drones that mate with the queen and then die. They are black and yellow in color. Their diet consists of large insects such as grasshoppers and flies as well as tree sap, fruit and honeydew. European hornets build their nests in hollow trees or hollow areas of buildings. These insects can also sting again and again. Their stings, like those of other wasps and hornets, carry venom.

Yellow Jackets

Yellow Jackets are a common species of wasp. They can measure anywhere from three-eighths to five-eighths inch long. They are colored black with prominent yellow stripes. Yellow jackets eat spiders and insects, and also any human food that they can find. Yellow jackets tend to live near human beings, and like to build their nests in dark, cool places. Yellow jackets can be helpful in pest removal, but they do have venom in their sting, which can be harmful to people who are allergic.

Paper Wasps

Paper wasps are another common species of wasp. They are one of the most frequently encountered species. They measure between three-fourths and 1 inch long. Some species of paper wasps are yellow and black, but others are brownish or reddish-brown. These wasps are named for the paper-like consistency of their nests. Paper wasps eat other insects, often caterpillars and beetle larvae. Their bites are not fatal as long as the victim is not allergic.