Summertime Stingers


Tips for protecting your summer picnics from unwanted pests

NO IDAHO SUMMER IS COMPLETE without an al fresco meal. And perhaps no such meal seems complete without inevitable yellowjackets or other stinging insects buzzing your face and arms and dive-bombing your entrées and drinks.

Why do they come, and are there ways to discourage such guests?

The answers are in a trio of publications by University of Idaho entomologists who tackle everything you want to know about stinging insects living in and around Idaho homes (see links below).

While the purpose of the three 8- to 16-page color-illustrated bulletins is to help homeowners consider a variety of ways they can manage these insects, the publications also offer a valuable guide to nesting habits and lifestyles of bees, hornets, wasps, yellowjackets, flying ants, mud daubers, and other common Idaho stinging insects.

Strategies to protect summer picnics

  • YELLOWJACKET TRAPS. Place 6 to 12 yellowjacket traps at intervals at least 20 feet from your proposed dining or gathering spot. (Such traps placed too close to the gathering area become yellowjacket invitations to your party.)
  • FLICK, DON’T SWAT, DON’T CRUSH BODIES. Do not swat at flying stinging insects; some will release air-borne chemicals—called alarm pheromones—that could stimulate a stinging attack from other workers. If a wasp lands on you, flick it away with your finger. Never crush the bodies of workers, especially near the nest; crushing also releases alarm pheromones that induce a mass attack.
  • MINIMIZE USE OF PERFUMES, colognes, soaps, or other scented body lotions when yellowjackets, bald-faced hornets, and paper wasps can be expected; these scents can be highly attractive to foraging wasps.
  • COMMERCIAL MOSQUITO/TICK REPELLANTS DON’T WORK against stinging insects. Indeed, it is possible that the scents of some products attract yellowjackets and other wasps.
  • COVER SERVING DISHES at outdoor picnics; clean up spilled drinks and food scraps; clear away dirty plates.
  • DO NOT LEAVE SOFT DRINK CANS OR BEER BOTTLES OPENED and unattended; yellowjackets can crawl unseen into open containers and sting painfully around the mouth.
  • KEEP LIDS ON TRASH CANS and dumpsters; clean to remove attractive odors or use disposable can liners; rinse cans and bottles before placing in outdoor recycling bins.
  • MOVE FOOD GARBAGE AWAY from patios or places where people congregate.
  • DON’T LEAVE moist pet foods outside.
  • APHID CONTROL. Control infestations of aphids and scale insects that produce honeydew on landscape trees and shrubs. They attract some stinging insects.
  • ELIMINATE DRIPS FROM FAUCETS, sprinklers, and garden hoses, especially during the dry parts of the summer. Puddled water attracts workers.
  • CLEAN UP ROTTING APPLES and peaches that fall from trees; pick cane berries before they over-ripen.
  • REPLACE LATE-FLOWERING landscape plants around decks and patios with non-flowering ornamentals.
  • WEAR WHITE OR TAN CLOTHES rather than light blues or bright pinks, reds, and oranges; close-fitting shirts and pants are better than loose-fitting clothes because wasps are less likely to become accidentally trapped against the skin.

University of Idaho Extension’s publications on stinging insects include:

BUL 852 Homeowner Guide to Yellowjackets, Bald-faced Hornets, and Paper Wasps, 16 pages,

BUL 853 Homeowner Guide to Minor Stinging Insects, 8 pages,

BUL 854 Homeowner Guide to Bees, 12 pages,

Adapted from a story by Mary Ann Reese first published in Programs and People. 

For more information on managing hornets and wasps, contact Ed Bechinski, UI Extension Entomology and IPM Specialist,