Yellow jacket

Yellow Jacket

Yellow jacket is a common name in North America for predatory wasps of the genera Vespula and Dolichovespula. Members of these genera are known simply as "wasps" in other English-speaking countries. Most of these are black and yellow; some are black and white like the bald-faced hornet, Dolichovespula maculata. Others may have the abdomen background color red instead of black. They can be identified by their distinctive markings, their occurrence only in colonies, and a characteristic, rapid, side-to-side flight pattern prior to landing. All females are capable of stinging. Despite having obvious benefits such as predation of pest insects, yellow jackets are sometimes considered pests themselves.

Biology and behavior

Yellow jackets are social insects that live in colonies containing workers, queens, and males (drones). Colonies are annual with only inseminated queens overwintering. Fertilized queens are found in protected places such as in hollow logs, in stumps, under bark, in leaf litter, in soil cavities, and man-made structures. Queens emerge during the warm days of late spring or early summer, select a nest site and build a small paper nest in which eggs are laid. After eggs hatch from the 30 to 50 brood cells, the queen feeds the young larvae for about 18 to 20 days. Larvae pupate, emerging later as small, infertile females called workers. By midsummer, the first adult workers emerge and assume the tasks of nest expansion, foraging for food, care of the queen and larvae, and colony defense.

Species

There are several species of yellow jackets, including the western yellow jacket, the southern yellow jacket, and the eastern yellow jacket. Each species has its own unique behaviors and life cycle, but all are social insects that live in colonies and have a distinct black and yellow coloration.

Sting and treatment

Yellow jackets are equipped with a lance-like stinger with small barbs, and typically sting repeatedly, though occasionally a stinger becomes lodged and pulls free of the wasp's body; the venom, like most bee and wasp venoms, is primarily only dangerous to humans if allergic, although anyone stung multiple times can be taken to the hospital. Treatment of stings involves cooling and/or the application of antihistamines or even epinephrine (adrenaline) if severe.

Control

Control of nuisance yellow jackets is best accomplished by locating and destroying the nest. Insecticidal dusts or aerosols are often applied directly into the nest opening. Yellow jacket traps can also be effective in reducing the number of wasps around a home, but they will not eliminate a nest.

See also

• Bee
• Wasp
• Hornet
• Insect sting