Lady beetles are widely recognized as beneficial insects. In the fall, they congregate to spend the cold winter months in sheltered sites: rock piles, tree holes, etc. However, the multicolored Asian lady beetle has a nuisance side. It is attracted to prominent terrain features, such as a vertical rocky outcropping. Following this visual cue leads many beetles to homes and buildings. After landing, the normally helpful insects crawl around searching for cracks or crevices to enter before settling for several months of inactivity. Some enter via gaps around windows, doors, and through ventilation openings. They will stay there during the winter and will remain active in the warm surroundings.
Adult Asian lady beetles are oval, convex, and about 1/4 inch long. Their color can vary widely from tan to orange to red. Most have several black spots on the wing covers, although the spots may be indistinct or entirely absent on some beetles. Most beetles have a small, dark M- or W-shaped marking on the whitish area behind the head.
More information and management recommendations are available in the UK Extension publication, Asian Lady Beetle Infestation of Structures (ENTFACT-416).
By Lee Townsend, Extension Entomologist