photo by G. McIlveen, Jr.
Ag Biz News Column
By: Chad Gulley
County Extension Agent–Ag/NR
Wasps are one of several stinging insects that can pose serious health and safety threats to humans. Many wasps’ species are beneficial pollinators and predators of other insects. It is when we get too close to their nests in which humans become a threat and are injured by their sting.
All wasps, bees, and ants belong to the scientific order of Hymenoptera. Many wasp species are social insects meaning they live in nests or colonies. The social wasp will defend its nest by stinging the intruder to the nest area and they are capable of stinging multiple times. Another group of wasp species are known as solitary wasps. They sting primarily to subdue their prey. Solitary wasps rarely sting humans. The solitary wasps primarily prey on spiders, crickets, cicadas, and caterpillars.
Wasp sting by injecting venom from the rear of the abdomen (tail) in which the stinger is a modified egg-laying organ; hence only female wasps can sting. Venom from wasps, ant, and bee stings is responsible for 40 to 100 deaths per year in the United States. Most deaths from insect stings result from allergic reactions to venom proteins and enzymes. Wasp stings typically result in intense pain, swelling and redness at the site of the sting. Stings around the head, eyes, and neck are especially serious. People allergic to wasps or bee stings should visit with their doctor about carrying an epinephrine emergency kit or other self-administered emergency kit.
Social wasps include paper wasps, yellow jackets, and hornets. Paper wasp nests contain 20 to 30 adult wasps and rarely more than 200 cells. Yellow jackets are primary ground nesters, but can construct aerial nests as well. Colonies of yellow jackets may get quite large with some containing up to 20,000 adult workers. Hornets construct a round, pear-shaped paper nest up to 3 feet long and almost always are constructed above ground often high in trees. Hornet colonies may contain 200 to 400 adults.
Solitary wasps include cicada killer wasp, cricket hunter wasps, and mud daubers. Cicada killer wasps dig galleries underground in lawns, gardens, and flower beds where the adult wasp lays eggs for her young. The cricket hunter wasps also live underground and primarily spend their time searching for crickets. After finding a cricket, they sting and capture the cricket and carry it to their nest laying a single egg on the victim eventually hatching and developing into an adult wasp. Mud daubers build small tube-like nests of mud under the eaves of homes, in attics, and other storage areas. Mud daubers primarily feed on spiders, including the brown recluse spider.
While most wasp species are considered a beneficial insect, in some instances they can cause injury to humans. Preventive measures around the outside of the home, barn or work area can reduce where they build their nests. Seal off openings under the eaves of roofs, attics, garages, storage sheds, barns, in open ended pipe pens, and a variety of other protected sites. Identification is important to determine if you have social or solitary wasp species around the home. Remember, social wasps will defend their nest and solitary wasps rarely sting humans.
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