Lady bugs in general are excellent predators of aphids on pecans, pine trees, ornamental shrubs, roses, and other plants. In 1979 and 1980, the USDA released the Asian lady beetle in Louisiana and Mississippi as a biological control over the aphids that were harming pecan trees. Because the Asian lady beetles have done so well at controlling aphids, pecan farmers no longer need to spray insecticides in many areas. By 1994, the Asian lady beetle had spread to Alabama, Georgia, South Carolina, and Florida. They have now made their way into the Midwest in increasingly large numbers.
Ladybugs feed mainly on aphids.
When their supply of aphids becomes exhausted during this time of year they move from the trees and shrubs to buildings for the winter. Even though the lady beetle is an excellent control for aphids and scales, they can become a nuisance when they gather in very large numbers during the autumn. For several days during autumn they typically cluster on sunny, southwest sides of light-colored rock outcroppings, in the corners of windows, door frames, porches and other spots. St. Olaf s light-colored limestone buildings provide ideal homes for the Asian lady beetle. Contrary to some reports, ladybugs do not bite or sting.