Many concerns with social wasps occur late in the season when colonies grow large and the above-ground nests of hornets and paper wasps become apparent. If the wasps are not causing a problem, the best solution is to wait until the nest is abandoned in the fall. The nest can be safely removed in the winter or, if left alone will break up during late fall and winter. Reducing European paper wasps nesting sites is possible if the sites are eliminated before they become established in late spring. This is done by sealing all openings that allow access to hollow tubing or similar materials. The interior of many kinds of children’s playground equipment are suitable nesting sites by this wasp and should be given special attention. Active nests causing problems can be destroyed with an insecticide. Insecticide applications are best made during late evening or cool periods in early morning, when the wasps do not readily fly. A variety of insecticides are currently sold for this purpose with active ingredients including permethrin, tralomethrin, bifenthrin, tetramethrin, allethrin, and esfenvalerate. Many of these are combination products that include a fast-acting, short-lived ingredient (e.g., allethrin, tetramethrin) with an insecticide that is more persistent in ability to control wasps (e.g., permethrin). Commonly sold wasp traps are effective only for yellowjackets. They are not attractive for paper wasps or hornets and will not assist in control of these types of wasps. For exposed nesting species, such as paper wasps, insecticides can easily be applied directly to the nest and control should be excellent. However, ground-nesting yellowjackets with only a small external entrance can be much more difficult to control since the nest may actually be some distance from the opening. Repeated insecticide applications are often required to destroy existing yellowjacket nests. Social wasps nests are more easily controlled early in the season when colonies are small. Nuisance problems with scavenging yellowjackets are difficult to manage unless all the nests are found and destroyed. However, nests are inconspicuously located and the wasps may fly as far as 1,000 yards from the colony while foraging, so complete control is difficult. Yellowjackets will regularly return to sites where food and water sources are available. Therefore, it is important to deter yellowjackets from visiting an area by eliminating all food sources (e.g., open garbage cans, pet foods). Water sources around the yard may also attract yellowjackets during hot, drought-stricken periods. For information on different types and characteristics of wasps, see fact sheet Nuisance Wasps and Bees.

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