Yellow Jackets

General Information

Yellow jackets comprise a subset of wasps belonging to the family Vespidae and genus Vespula

Although nearly 20 different species of yellow jackets live in North America, only five classify as pests. Of the five pest species, the eastern yellow jacket and the German yellow jacket rank among the types most commonly found. While all yellow jacket species naturally control the populations of other troublesome insects, the pest varieties are categorized as such because the flying, stinging insects regularly cross paths with humans when scavenging for food. The powerful stings and often aggressive nature of yellow jackets make removal of the insects particularly difficult without the assistance of a pest control professional.

Appearance & Identification

What do yellow jackets look like?
Aptly named, yellow jackets feature distinctive patterns of yellow and black bands on the abdomen. Three legs extend from each side of the body, while a pair of transparent wings enables the insects to fly. Shaped like wasps, yellow jackets generally measure about a half-inch in length and also boast a set of antennae extending from the head by the eyes. Unlike bees, which are hairy, yellow jackets and other wasps tend to have smooth bodies.

Habits/Habitat

Social by nature, yellow jackets live together in colonies that house as many as 4,000 workers. A female queen establishes and presides over each colony. The preferred habitats of the yellow jacket varieties depend on the particular species. Eastern yellow jackets typically construct underground nests, often taking over burrows abandoned by other animals, while German yellow jackets generally live aboveground in enclosed areas like attics or spaces behind walls. Yellow jacket colonies usually peak in population during late summer and early fall. Often regarded as aggressive insects, yellow jackets actively defend the nest by stinging intruders and other perceived threats.

Diet

What do yellow jackets eat?
Yellow jackets adhere to a diet largely composed of proteins and sugars. The scavenging insects regularly invade cookouts, dumpsters and trash cans, and other outdoor settings where food sources are readily available. Yellow jackets frequently take a particular interest in sweets like fruit and soda. The foragers also perform a valuable environmental service by preying on soft-bodied insects such as flies, caterpillars, and other agricultural pests.

Reproduction

Female queens mate in the fall, overwinter, and emerge in the spring to lay eggs and establish a new yellow jacket colony. Each queen lays about 40 to 70 eggs initially. After the first batch hatches into worker yellow jackets, the queen maintains responsibility for continuing to lay eggs while the workers forage for food, expand and defend the colony, and care for the newly hatched. Yellow jacket colonies continue to grow in population through the summer. The insects mate during the fall as the weather turns colder. After mating, females leave the nest to hibernate while males die. With the exception of fertilized, hibernating females, yellow jackets typically do not survive cold winters.

Problems Caused by Yellow Jackets

As territorial creatures that sting when threatened, yellow jackets pose serious problems when the insects construct colonies in areas within close proximity of humans. When yellow jackets sting, they inject a small amount of venom that can cause allergic reactions ranging from slight pain and swelling to wheezing, faintness, and more serious symptoms requiring immediate medical attention. Unlike bees, which have barbed stingers designed for one-time use, yellow jackets enjoy the ability to sting repeatedly. Furthermore, yellow jacket stings produce odorous chemicals that attract and encourage other yellow jackets to join in on the attack. Because yellow jackets defend the colony so aggressively, the insects often prove extremely difficult and dangerous to remove.

Signs of Yellow Jacket Infestation

The strongest indicator of a yellow jacket infestation is the presence of a paper nest. Yellow jackets construct paper nests either underground, behind walls, or hanging from the eaves of attics or the branches of trees. The paper-like quality of the nests comes from the chewed up cellulose yellow jackets use to build the habitations. When constructed aboveground, yellow jacket nests often resemble the shape of teardrops. Nearby infestations may also produce groups of worker yellow jackets hovering in and around dumpsters and trash cans.

Prevention

Residents can prevent yellow jacket infestations by eliminating food sources as much as possible. Homeowners, landlords, and park managers should empty and clean outdoor trash receptacles on a regular basis. Trash cans in public outdoor spaces should be placed far enough away from picnic areas to minimize encounters with foraging yellow jackets. When not in use, outdoor dumpsters and trash cans should remain covered. In the event of a serious infestation problem, contact a professional pest control specialist to avoid any potential complications resulting from painful, and sometimes dangerous, yellow jacket stings.

Yellow jackets are black and yellow patterned insects that are found buzzing around trashcans and picnic tables. They are considered a nuisance and can deliver a painful sting. However, most yellow jackets are very beneficial.

Yellow jackets eat other insects, mostly pests, and can help keep gardens free of flies and caterpillars. They are also scavengers. Usually, they will eat garbage, meat and sugary substances, like sodas. Yellow jackets seek out sugary foods at the end of the summer due to limited sugar production in the larvae. Yellow jacket adults rely on this sugar production from the larvae for food. That’s why yellow jackets can be found in greater abundance as summer wanes.

Yellow jackets build nests out of cellulose or paper, and a queen does the initial work. These nests are usually built underground or in crevices that exist naturally, in rocks or trees. The queen, who has hibernated through the winter, will build the nest and lay eggs, creating a colony. The queen begins the colony by laying eggs and feeding them.

The colony will grow through the summer. The queen continues to lay eggs and produces reproductive males and females. These yellow jackets then leave the nest to mate. The colony begins to die off and the nest becomes abandoned

The inseminated females are the only ones to survive the winter, becoming the new queens in nests they will build when they emerge in the spring.

A yellow jacket queen is the most important part of the colony. The queen begins the colony anew each year. Every winter, a queen will hibernate from a colony that has died out. In the spring, she will begin to rebuild the yellow jackets’ nest.

The yellow jacket queen begins the nest with cellulose or paper that she has chewed up. About the size of a golf ball, the nest created houses a few cells. The queen will lay eggs in these cells. Eventually, this small nest will have 30 to 55 cells, covered by a larger paper envelope.

The yellow jacket queen will continue to lay eggs. The first larvae to hatch will be 5 to 7 worker bees. These sterile females will take over the queen’s nest building and larvae feeding duties. This leaves her free to produce more eggs.

Late in the season, queens and males will leave the nest to mate. The only yellow jackets that survive the winter are the inseminated females that will hibernate and begin the process over in the spring.

Yellow jackets can be aggressive, especially when their nests are disturbed. Unlike bees, yellow jackets can sting multiple times because their stingers are not barbed. Never attempt to remove a yellow jacket nest. Seek the help of a pest control expert.