Western Yellow Jacket
Of the 17 different yellow jacket species in North America, the most common is the western yellow jacket. The western yellow jacket is easily identified by its black and yellow stripes, defined waist and long wings, which lay laterally against the body when at rest. They range from 1/2-inch to one inch in length and reach largest numbers in summer and fall.
At its peak in the fall, a western yellow jacket colony may contain thousands of insects, but in the winter, worker yellow jackets perish while fertilized queens hibernate. The queens establish new nests in the spring, laying eggs to start new colonies. When the first generation of wasps reaches maturity, they are workers. They begin nest building and tend to the queen and subsequent eggs and larvae.
Yellow jackets are sometimes considered ecologically beneficial, as they pollinate flora and feed on flies, beetle grubs, caterpillars and other pests. However, western yellow jacket can be a scavenger on human food and are known to be a pest near trashcans and picnic sites.
Western yellow jacket are ground-nesters and are likely to build their colonies beneath porches or in cracks in sidewalks, steps. They may also construct nests in bushes or low branches. Because they live close to or within the earth, western yellow jacket wasps are likely to come into regular contact with humans.
The sting of the western yellow jacket is painful and may cause severe allergic reactions in some individuals. A common instinct upon encountering yellow jackets is to swat at or run from them. However, sudden motion further aggravates yellow jackets and may encourage attacks.
How Big Does a Yellow Jacket Nest Get?