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Last weekend when I was outside, I got reminded that it is time to be on the lookout for a few of those nuisance insects we annually deal with. The insects I am referring to are the Asian lady beetle, boxelder bug, and brown marmorated stink bug.

Asian lady beetles can vary in color, but they all can be identified by looking at their thorax (area between the head and wing covers) for a black “M.” Sometimes the “M” is darker and more obvious, but it is always there. Asian lady beetles will not stay outside for long following a cold snap. Therefore, it is important that you take time and fill any cracks or holes leading into your house. Once inside the house, the beetles essentially remain in a hibernation-like mode for several months. After warm weather hits, the beetles spring back to life and begin crawling around intensifying the nuisance factor.

Purdue publication E-214-W, “Asian Lady Beetles,” list four good control methods to use when handling these beetles. First, seal them out of your home by caulking and repairing openings. Second, use pesticides as a perimeter treatment. Third, use indoor pesticides to provide temporary control. The previous mentioned publication provides a list of pesticide products that can be used. Lastly, vacuum or sweep the beetles up.

In comparison, adult boxelder bugs are dark brown to black in color with red lines on their backs. Their young are wingless and have red bodies with a yellow line down the center of it. They are a nuisance because they invade homes once fall temperatures begin to drop. They squeeze into cracks in the foundation, windows, doors, and under siding and shingles in search of a way into a house. Thus, it is important that you take time to seal off all openings to your house.

Once in the house, you can get rid of boxelder bugs by using household insecticides containing pyrethrins or resmethrin. Please remember to read and follow all labels when using any insecticide. However, it might be easier to use a vacuum cleaner to get rid of the boxelder bugs instead. For more information look online for Purdue publication E-24-W, “Boxelder Bugs.”

Lastly, brown marmorated stink bugs are mottled brown in color and have bands of light and dark brown on their antennae. They can emit a pungent over when they are disturbed. In the spring and summer, they are found outdoors, but like the Asian lady beetle and boxelder bug, they find their way indoors during the fall. They will enter through cracks and crevices, chimneys, and any other small holes that might exist. Therefore, trying to seal the cracks and crevices, when possible, is the best defense from these insects.

Inside, they don’t do a lot of damage, but are a nuisance and can create an odor. When you spot a brown marmorated stink bug in your house, consider putting it in a container of soapy water. This will kill the insect and lessen the impact of the odor. For more information about brown marmorated stink bugs, check out Purdue publication E-273-W, “Brown Marmorated Stink Bug in Homes.”

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