People can control stink bugs using a variety of methods, many of which are inexpensive. Sealing the home or building is the first line of defense, followed by removing or reducing food sources. Some people have had success with natural methods such as kaolin clay, diatamaceous earth and light control, while others simply vacuum up the insects they see. Insecticides also can work, but these are only appropriate to use outside of the home, and they don't work on all species or for very long.
About the Insects
Stink bugs, also called shield bugs, are insects in the Pentatomidae family, and as their common name implies, they have a foul smell. Brown or green in color with a somewhat boxy or trapezoidal appearance, they emit small amounts of a noxious substance from glands under their bodies, which deters predators and sends signals to other stink bugs. Native to Asia, they have made their way into other regions where there aren't many creatures that feed on them, which has allowed them to reproduce rapidly and in large numbers. In the home, they are relatively harmless, but they do cause problems in agriculture, making crops unfit to eat.
One of the most basic ways to handle these pests is to make sure they cannot get into the building. This isn't as easy as it sounds, because the average home has many potential entrance points. A good start is to apply weather stripping and caulk around doorways and windows, and to install door sweepers. Chimneys and air vents also should have screens, and sometimes, it is necessary to replace structures with old or rotting wood, as the insects like to hide in it. These improvements might cost a little money, but they often will make a home more energy efficient and improve the value of the property in addition to keeping it pest free.
Plant and Lawn Care
Most species of Pentatomidae feed on plants and use them for cover, although a few types are predators that eat other bugs. They happily feast on fruits, beans, peppers, pecans, at least 70 different types of ornamental plants and other field crops, as well as weeds and grass. An easy method of control is to remove their food sources. Plants that are very close to a house should be taken out, which will force the insects to cross barren ground to gain access to the structure. Keeping grass heights low with routine lawn maintenance also helps.
Kaolin Clay and Diatamaceous Earth
After weeds and other plants around a building have been reduced or completely eradicated, a good trick is to sprinkle remaining plants with kaolin clay, either as a powder or as a solution. A harmless substance often used in cosmetics, this mineral coats plants, making it difficult for the insects to lay eggs and feed on them. Any clay on fruits and vegetables simply needs to be washed off before someone eats the food.
Another natural deterrent is diatamaceous earth, which is a form of sedimentary rock that crumbles into a powder easily, and which includes the fossils of hard-shelled algae called diatoms. These fossils give the powder a mildly abrasive quality, and when bugs try to crawl over it, the diatomaceous earth scratches their exoskeletons and causes them to dehydrate and die. It also is thought to get caught up in and cut their joints, so it is an excellent tool for discouraging their movement. It is important to use only food grade versions with this tactic, because commercial types have added chemicals that can be toxic. Patience is also a must, as it takes some time for the insects to die.
A very common remedy that often works to control an infestation is to use a simple solution of soapy water — people have used detergents as a cheap insecticide for at least 200 years, according to Colorado State University. Experts still are researching exactly how it works, but they think it causes problems with the cell membranes or waxy coating on the exoskeleton, making it easy for the bugs to sink and drown, or, when out of water, to dehydrate. Many people have had success applying some with a spray bottle, which works well for ones on screens. Other people put a small amount in a regular bottle or jar, using the lid to knock the bugs inside, and some individuals prefer to use an open bucket, particularly if there are a lot of insects to deal with. Experts sometimes recommend spraying the outside walls of homes with a soap solution as well.
Vacuums are often an effective tool against stink bugs, and many people like this removal method because it is a quick way to handle many insects at once, and because it doesn't require any chemicals. Once they are in the vacuum, it takes minimal effort to dispose of the bag or canister contents. One note here, though, is that it's necessary to get a separate machine, leaving the regular one for cleaning alone, because any insects that die during the collection process will make it stink.
Like other insects, stink bugs are attracted to light. The simple action of keeping blinds or curtains closed at night can reduce the number of them around a home. Some homeowners find that they have to stop running porch lights or remove garden and pathway fixtures to stop the problem.
A tip from Bayer Advanced™ is to rub dryer sheets with a powerful scent over screens, which reportedly keeps stink bugs from getting in by up to 80 percent. The same company recommends hanging a damp towel outdoors where the insects are a problem. Once the bugs congregate on it, a person can take the towel and toss it in bucket of soapy water. Although squishing them isn't usually a good idea, if they are outside, killing a handful of them can release the smell that will warn others away. Rick Steinau of Ask the Exterminator also recommends electrocution systems for spaces such as attics.
Chemical insecticides which are formulated for various stink bug species are another control option. Many insecticides are highly toxic and are difficult to deal with, however, so they should really only be considered as a last resort. Most professionals do not recommend this method for use within the home, not only because of the potential danger to people and pets, but also because the dead insects can attract other pests that will feed on the bodies. Even when used outdoors, this technique usually doesn't work for more than about a week, depending on the exact ingredients.