By Marcia Anderson
Along with the azaleas, dogwoods and spring bulbs, yellow jackets have also awakened – just in time for playground and BBQ season. Yellow jackets, wasps and hornets are beneficial insects, but they can be a health hazard due to the reactions that some people have to their painful stings.
Early Action Prevents Later Trouble: You can often avoid severe yellow jacket problems by eliminating workers and nests in late spring and early summer when yellow jacket workers are few and their nests are still small.
If there is a chronic problem with yellow jackets around your school or community playgrounds, picnic areas or fields, inspect the area to locate the nests. Nests can be found in the ground, under eaves and in wall voids of buildings. Ground nests are frequently located under shrubs, logs, rock piles and other protected sites. Entrance holes sometimes have bare earth around them. Nest openings in the ground or in buildings can be recognized by observing the insects entering and leaving. Yellow jacket nests can also be found in fence posts, play equipment and picnic table supports with unsealed openings.
The environmentally preferable way to reduce stinging insects is to use Integrated Pest Management (IPM) techniques. IPM is an effective, environmentally sensitive and sustainable approach to managing pests by combining biological, cultural, physical and chemical tools in a way that minimizes economic, health and environmental risks. Yellow jacket and other stinging insect presence can be significantly reduced when IPM procedures are implemented.
Prevention and Habitat Modification: Given the potential seriousness of stings, the objective of yellow jacket management is to reduce encounters by eliminating their prime foraging habitats through good sanitation practices and awareness. The most effective ways to manage yellow jackets are to reduce their access to food in the vicinity of human activities, and to use physical controls such as nest removal and trapping.
Reduce access to food: Later in the season, yellow jackets are attracted to protein foods. Any food left outdoors, open garbage containers or uncovered compost piles should be removed or covered. Wasps imprint food sources, and will continue to search an area for some time after the food has been removed. All refuse containers should periodically be cleaned of food wastes and should be emptied frequently to prevent the contents from impeding the closure of the lid. Garbage cans should have lids and dumpsters should have vertical spring-loaded swinging doors.
Trapping: Trapping will not eliminate yellow jackets, but can help to reduce their numbers. Various types of traps are baited with liquid or dry attractants and will allow insects to enter, but not escape. Place the traps around the perimeter of the area you want to protect so that you draw the yellow jackets away from the people. Aggressive trapping will significantly reduce the number of fall-foraging yellow jackets and the risk of stings. Do not skimp on the number of traps, as you may need lots of traps to get effective population reduction. Place traps according to the manufacturer’s directions. Empty the traps and change baits frequently to keep the traps effective. Traps should always be placed out of reach of children.
Following these steps in the spring should lead to fewer incidents with yellow jackets and other stinging insects in the late summer and autumn. See Virginia Tech’s website for more information on IPM for yellow jackets and wasps. Also, check out EPA’s website for information on smart, sensible and sustainable pest management in schools.
About the Author: Marcia is with EPA’s Center of Expertise for School IPM in Dallas, Texas. She holds a PhD in Environmental Management from Montclair State University along with degrees in Biology, Environmental Design, Landscape Architecture, and Instruction and Curriculum. Marcia was formerly with the EPA Region 2 Pesticides Program and has been a professor of Earth and Environmental Studies, Geology, and Oceanography at several universities.