Yellowjackets Are Good Guys! While they rarely get credit for it, yellowjackets are valuable beneficial insects in your yard. They destroy great numbers of other insects to feed their young. Many of their victims are significant pests such as flies and caterpillars--including cabbage worms, corn earworms and armyworms. Their only natural enemies are skunks and raccoons who raid yellowjacket nests for food.

Yellowjackets are also scavengers, cleaning up decaying matter in the environment. In residential areas this brings them into contact with humans as they visit picnic tables and garbage cans. Then they become potentially harmful, especially late in the season when their colonies are dying off for the winter and they are frantic to find food. At this time they are more aggressive and likely to sting.