The yellow jacket is a large native wasp. It is a social insect and lives in a colony. Known for their painful sting, yellow jackets have large shiny black and yellow bodies. An attack from a swarm of wasps or hornets can be life-threatening. Like bees, only female wasps have the ability to sting. The sting is a modified ovipositor, an egg laying structure, which males do not have. Yellow jackets, along with other wasps and hornets, can sting multiple times and will attack people or animals for no provoked reason.

The social structure of a wasp colony is similar to that of a honeybee, with the majority of the population made up of sterile female workers. The queen wasp is the only female to reproduce and lay eggs and there are a limited number of males, or drones, that mainly exist for mating purposes.

Wasp nests are built by the queen wasp and are made out of wood fibres mixed with saliva to make a paper-like material. The nest can be attached to trees, eaves, wall cavities, or made under the ground.

The colony starts with one fertilized female. The queen is the only wasp that overwinters and the rest die off in the cold weather. In the spring the female builds a nest and lays her first set of eggs. She stays in the nest as the larvae grow and feeds them a diet of chewed-up insects. The resulting worker wasps take over the queen’s job of feeding the larvae. The queen spends the rest of her life laying eggs. The colony grows quickly and towards the end of the summer male wasps develop from unfertilized eggs and later mate. By winter the colony, including the old queen will die, and the young mated females will leave to hibernate, usually in sites under the soil.

Yellow jackets feed on a diet rich in protein and carbohydrates, including sweet flower nectar and fruit. Unlike honeybees and bumblebees, yellow jackets are carnivorous, eating insects and carrion as a source of protein. Human food is also attractive to yellow jackets and other wasps. Carbonated beverages, juices, candy, and some kinds of meat will attract wasps outdoors. They can become a nuisance at a picnic, around homes and outside restaurants, especially in late summer when their numbers have increased.

Because of their interest in nectar, the yellow jacket wasps are considered to be part of the main pollinating insect group. They prefer flowers with easily accessible nectar sources. Although they do not transfer large amounts of pollen because of their hair-less bodies, these wasps do appear in great numbers and therefore accomplish some pollination.