Many people were asking in the early spring if our extreme winter temperatures were going to affect the insect population. From where I sit, the answer is no. The extension office is getting plenty of calls about insects.
Our insect(s) of the week seems to be hornets, yellow jackets, mud daubers and paper wasps. Scientifically speaking, all of these critters are members of the wasp family Vespidae. They are feared for their stings, and some are considered a nuisance for their nesting habits.
In many ways we should be grateful for these insects. Most wasps are hunters, feeding on other insects, many of which are considered “bad guys.” It is hard to show respect to an insect that can sting or bite you.
Hornets build big paper-like nests. And they tend to surprise people. One day, out of thin air, there is a basketball-size nest attached to your home, or a tree or a shrub in the yard. Disturbing such a nest often brings out an angry mob of hornets planning to defend their home.
Most times, I advise people to leave nests alone if they’re in isolated areas not directly in the normal traffic pattern. Nests hanging high in trees seldom lead to problems with humans or pets. Nests under the eaves of houses or barns, in low traffic areas, can be left until late fall or early winter.
There are times, however, when removing the nest may be the best idea. For example, one caller told me hornets had nested immediately above the entrance to her home. Another said a nest was hanging in a burning bush about 3 feet off the ground, bordering an open space where the neighborhood kids play football. There are numerous products on the market that can be used to spray hornet nests from a distance. Often, you will find you need to re-treat the nest after a few days, as untreated juveniles emerge from deep in the nest.
There are more than 20 species of yellow jackets that live in Indiana. You can generally break them down into two categories: ground nesting and tree (hollow area) nesting.
Ground-nesting yellow jackets are fascinating to me, but they can be a huge problem in a lawn or field. Over the course of a summer, these insects hollow out an area just below the turf, and make a hidden basketball-size paper nest with a grass roof. If you are careful, you might see yellow jackets flying in and out of the hidden opening, delivering food to the colony.
Ground nests are often discovered accidently when a person is mowing or walking. The hollowed out space cannot support the weight of a human, pet or lawnmower. One minute you are enjoying the outdoors, the next thing you know, you are being stung by angry yellow jackets.
Once you find a ground nest, you can treat it with several products. I prefer dusts over liquids. The dust products are easily sprinkled into the entrance. Each insect is exposed to the dust as it leaves the nest. Eventually, the adults in the colony die off. However, the nest should be treated again in five to seven days, because some of the young brood will be coming into adulthood after the first treatment.
Tree nesting yellow jackets sometimes use our buildings as their homes. The “queen” will find a small hole in the wall, and use space between the walls for a nest. As the colony grows, it can quietly remove bits of wallboard or insulation, even breaking through at times to enter your living space.
Yellow jackets in the wall of a home are very hard to remove without special equipment. The nest is often several feet from the entry point, so simply spraying the hole with wasp killer or plugging the hole up will do more harm than good. In fact, I have heard horrible stories of living rooms, kitchens and bedrooms full of angry yellow jackets. Wall-nesting yellow jackets are best removed by a professionals if you have little knowledge of yellow jackets or construction.
One inventive person used a vacuum cleaner to suck the insects up as they left the entry hole. The strategy worked for a while, but in a few days, replacements emerged from their nursery and the yellow jackets went back to work.
Mud daubers and paper wasps are known for attaching their nests on the walls of homes, making a mess and scaring people, usually for no reason. If the nest must be removed, the wasp and hornet sprays on the market will do the job. Remember, those wasps are great predators, helping to keep the insect population at tolerable levels.
Jeff Burbrink is an extension educator in agriculture and natural resources. Write to him at 17746 E. C.R. 34, Goshen, IN 46528; call 533-0554; or fax 533-0254.