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What is red and has black polka dots all over? -Novi MI

Asian lady beetle, or Japanese ladybug

Asian lady beetle, ladybugAre lady bugs surrounding and invading your home by the thousands? millions? If so its probably not lady bugs, its the Asian beetle. Asian beetles have become a homeowners worst nightmare. Asian beetles, which are sometimes mistaken for ladybugs or lady bird beetles, are familiar insects in many parts of Michigan. For the most part, Asian beetles are beneficial predators that eat aphids, scale, insects, and many other pests that injure plants in gardens, landscapes and agricultural settings. However, in many places the multicolored Asian lady beetle has become a household pest. This beetle feeds on aphids and other soft-bodied insects that dwell on crops and trees. Soybean crops are reportedly a favorite of Asian beetles. Of course, spring time is also a good time to have an Asian beetle outbreak. Why do we have such large numbers – sometimes epidemic numbers of Asian beetles? You can thank science and the US government.

Multi-colored Asian beetles are slightly larger than most native lady beetles, with adults Asian lady beetle, ladybugmeasuring 3/8 inch long 3/8 inch wide. They are oval or convex in shape, and yellow to red in color (without black spots on wing covers). The beetles’ spots, which can vary in size and pattern, number from no spots to as many as nineteen; however, nineteen is the most common number. The head is usually concealed beneath the disk-shaped pronotum, which is cream to yellow in color with a black ‘M’ design in the center. Asian beetle larvae are elongated, flattened, and covered with minute tubercles or spines. They are often described as alligator-shaped. The eggs, which are laid upright in clusters of about twenty, are oval and yellow.

Asian Lady Beetle Damage

Asian lady beetle, ladybugThe greatest damage caused by the multicolored Asian lady beetle is the discomfort they give to homeowners. It is not uncommon for tens of thousands of beetles to congregate in attics, ceilings and wall voids. When the heating is turned on the beetles tend to move around inside these voids and exit into the living areas of the home. In addition to biting, they exude a foul-smelling, yellow defensive chemical, which will sometimes cause spotting on walls and other surfaces. Most people are only annoyed by the odor of these chemicals. However, some individuals experience an allergic reaction to the defensive excretions. Sinus irritations and mild skin irritations have been reported subsequent to encounters with the Asian beetle.


Light traps or insect “zappers” may provide relief from beetles flying or crawling around the exterior of homes with its light source. Asian Lady Beetles will be attracted to the trap and be “zapped”. DO NOT use this type of light trap indoors. Light traps are most effective at night when there are no competing light sources. The tray may need to be emptied on a regular basis as the dead beetles pile up. Do not place this type of trap in the open. It needs to be protected by an awning, eave or other weatherized covering to protect it from rain.

Pest proofing or sealing the outside cracks may help to prevent Asian beetles from getting inside. This can be done by sealing all outside cracks and crevices around doors, windows, siding, utility pipes and other openings with a good quality silicone or silicone-latex caulk. Window screens should not have any tears and should fit snugly inside the window frame. Install insect screening over attic and exhaust vents. Take measures to exclude Asian beetles before late autumn when they begin to seek over-wintering sites – potentially in your home!

Using pesticides may be the only solution for eliminating Asian beetles. Non-chemical control measures will provide some control, but spraying may be the only real solution.

Give Sergio’s a call today to set up an appointment. (248) 932-0018

Call Sergio' s Today! (248) 932-0018

Call Sergio’ s Today! (248) 932-0018