They are oval in shape, about 1/3 inch long, and are pale orange in color with black spots on the wing covers. As the name states, the Asian lady beetle is native to eastern Asia. In Asia, they occur in at least 100 different color forms, including black forms with orange spots. One of the Asian lady beetle’s most distinguishable features is a prominent “M”-shaped marking behind its head. Many people often mistake the Asian lady beetle for the ladybug, as they are similar in appearance.
These beetles were imported and released into the United States to naturally control pests like alphids, which destroy crops, gardens, and landscapes. Because the Asian lady beetles feed on these pests, there is less need for insecticides on the crops, making them beneficial to farmers and gardeners. They are an important predator of soybean aphids, a pest of soybeans in Midwestern states.
Just like boxelder bugs, Asian lady beetles congregate on the west or southwest sides of light colored buildings where there is warmth and sun exposure. This happens during fall as they search for overwintering sites. During nighttime, the beetles move into leaf litter, underneath logs or boards, or to other protected areas like inside buildings. They particularly like buildings that are adjacent to wooded areas, where their food is. They can enter walls of a building through cracks and crevices. Most stay in the wall spaces as an overwintering spot, while some will come indoors. Warm days of late winter and early spring, or warmer temperatures or lighting in living areas may cause beetles that have been hiding to become active and to search for an exit.
While mostly harmless, and even beneficial, Asian lady beetles can bite and break human skin while searching for moisture or food. They defend themselves through “reflex bleeding”, in which they secrete a yellow fluid that can stain carpets, walls, or curtains, and omit an unpleasant odor. Exposure to dead Asian lady beetles can cause allergic reactions in some people.
Prevention is the key to keeping multicolored Asian lady beetles out of your home or building. As pests seek refuge in homes and other buildings in response to changes in weather, it is important to deny entry by pest proofing. You can take the following steps to block their entry before they end up inside:
Tips to get rid of Asian lady beetles/ladybugs:
- Make sure doors are tight fitting. Install door sweeps or thresholds at the base of all exterior entry doors. Apply caulk along bottom outside edge thresholds to exclude ants and other small insects. Repair gaps and tears in door screens.
- Make sure windows are properly sealed. Caulk cracks around windows, as well as around doors, fascia boards, etc. Repair gaps and tears in window screens.
- Seal utility openings. Check where wires and pipes enter the foundation, and siding around outdoor faucets, clothes dryer vents, gas meters, and telephone/cable TV wires for gaps. Plug any holes as necessary. Screen or seal any ventilation openings in attics.
Depending on the construction of your home or building, different precautions may be taken. If multicolored Asian lady beetles have already made their way indoors, you may physically remove them with a gloved hand, a broom and a dust pan, or a vacuum. Check around the building exterior if they are found during fall, as they can be found congregating in warm or sunny areas.
As always, give us a call if you are having a pest problem and we will happy help. Batzner Pest Management’s Asian Lady Beetle Program is precisely designed to help control these pest infestations.