Stinging Insects

Beware of stinging insects -- especially yellowjackets

Brian Jervis: Ask a Master Gardener

Saturday, August 22, 2015

Q: My husband has been stung by some sort of wasp while mowing the yard, twice now, both in the same area of the yard. It looked like a wasp, what can I do? L.M., Tulsa

A: There are several wasps and bees which may sting, some more so than others. The most aggressive insects are yellowjackets, paper wasps and Africanized bees.

According to records, Africanized bees are found in 40 Oklahoma counties in the southern and southwest part of the state but not in our area.

From your description of being stung in your yard and the fact they nest in the ground, the most likely insect to do this is a yellowjacket.

There are many other insects — bees and wasps — with abilities to sting but rarely do so unless overtly provoked. Of the stinging insects, only the females sting; their stingers double as an egg-laying device. Wasps can sting multiple times, but all bees sting only once, losing their stinger and venom bag after the sting.

It is important to realize that most of these stinging insects help control undesirable pests, and some are important pollinators. They shouldn’t be killed unless there is a documented problem or foreseeable threat.

Yellowjackets come in three different varieties — Eastern and Southern yellowjackets and baldfaced hornet. The first two varieties are usually yellow and black and nest in the ground, in old logs or in voids inside the walls of buildings. Their underground nests are hidden but are similar to the baldfaced hornet nest, which is above ground and is a large cone-shaped paper-mache structure.

Yellowjackets also congregate around open garbage, old fruit or any wet sugar source such as open soft drinks where they may be a threat.

The ground nests may be difficult to locate, but if you watch for yellowjacket activities, you should be able to locate the hole, usually less than an inch in diameter.

Once located, use an insecticide — either spray or dust — into the hole then plug the hole with an insecticide-soaked cotton ball. Do this at night when they will all be home and less aggressive.

OSU fact sheet “Paper Wasps, Yellowjackets and other Stinging Wasps” has complete information about controlling wasps, which includes some do’s and don’ts about avoiding stinging insects:

·       Do not use sweet-smelling colognes, perfumes and hair sprays in wasp areas.

·       Do not wear bright-colored clothing; wear tan, khaki, and dark-colored clothes.

·       Do not picnic, sit, or stand near trash cans, fallen fruit, or other wasp feeding sites.

·       Do not swat or move rapidly when a wasp visits you or your food or drink; move slowly.

·       Do not approach a nest; if you do disturb a nest, run away from attacking wasps.

·       Do clean up food and drink refuse, clean trash cans, and fit them with a tight lid to reduce wasp visits.

Garden tips

§  August is a good month to start your fall vegetable garden. Bush beans, cucumbers and summer squash can be replanted for another crop. Beets, broccoli, carrots, potatoes, lettuce and other cool-season crops can also be planted at this time.

§  Discontinue deadheading roses by mid-August to help initiate winter hardiness.

§  Irrigated warm-season lawns such as Bermuda and zoysia can be fertilized once again; apply 1 pound N/1,000 square feet this month. Do not fertilize these grasses after the end of August. Do not fertilize tall fescue lawns in summer; fertilize in late September after it cools and again in November.

§  This time of the year is generally not the best time to prune, but if you have damage to trees and shrubs due to storms, prune out the damage now.