Wasps

The most familiar wasps to most people are the relatively large social species, such as hornets, yellow jackets, and potter wasps, all in the family Vespidae. These wasps are brightly colored, have yellow-and-black or white-and-black stripes on their abdomen, and buzz audibly when flying. Adults of these species catch insects as prey, and they also feed on nectar and soft fruits. Vespid wasps build nests out of paper, made from the cellulose fibers of well-chewed wood. These wasps sometimes attack people who have stepped on their nests This female wasp of the family Mutillidae mimics the appearance of dangerous species of ants to ward off predators. © George Bernard, National Audubon Society Collection/Photo Researchers, Inc. Reproduced by permission.
or are too close for the wasps' comfort. The stings of these large wasps, often delivered in multiple doses, can be very painful and often cause a substantial swelling of the surrounding tissue. Some people develop allergies to the stings of wasps (and bees), and fatalities can be caused if these hypersensitive individuals are stung.

The name yellow jacket is applied to various ground-nesting species in the genus Vespula, including V. pennsylvanica in western North America and V. maculifrons in the east. The closely related bald-faced hornet (V. maculata) is a widespread and abundant species in the United States and Canada. The polistes wasp (Polistes fuscatus) builds paper nests that are suspended from tree limbs or the eaves of roofs. The potter or muddauber wasp (Eumenes fraterna) makes clay nests suspended from branches of trees and shrubs.

The spider wasps (family Pompilidae) build their nests in the ground and provision them with paralyzed spiders. One of the better-known species is the tarantula wasp (Pepsis mildei) which is famous for its skills at hunting and subduing tarantula spiders which are much larger than the wasp. Virtually all tarantulas that are located by a tarantula wasp become living pantries for the young of these efficient predators.

Chalcid wasps are various, minute-bodied species of parasitic wasps in the superfamily Chalcidoidea made up of several families. Adult chalcid wasps feed on nectar, plant juices, or honeydew, a sweet secretion of aphids. The young wasps, however, are reared in the bodies of arthropods, usually eventually killing the host. Some species of chalcid wasps are bred in captivity in enormous numbers and are then released into fields or orchards in an attempt to achieve a measure of biological control over important insect pests. For example, the trichogramma wasp (Trichogramma minutum), only 0.1 in (2.5 mm) long, will parasitize more than 200 species of insects. This useful wasp has been captive-reared and released to reduce populations of bollworms of cotton, corn earworms, and spruce budworms in conifer forests.