This week we are seeing the annual swarming of lady bugs, or lady beetles. Based on reports from other states and from all the phone calls we have received, we may see particularly high numbers of lady beetles this fall. The cold temperatures last week followed by daytime highs in the 70's this week triggered the swarming to start. It should continue until we get more constant cold weather.

Lady beetles swarm in the fall as they try to find a sheltered place where they can hibernate during the winter. There are about 400 species of lady beetles in the U.S. Most of these are considered to be *good guys* or beneficial insects, because they eat aphids and other insects that feed on plants. However, the problem with lady beetles coming into homes has become worse in recent years with the arrival of the multicolored Asian lady beetle. This species is a predator of aphids, scales, and other small insects on trees and other plants. In their native range in Japan, Asian lady beetles swarm to cliffs to search for crevices for overwintering sites. However, houses and other buildings seem to be attractive alternatives to cliffs. These beetles enter homes by slipping through cracks around doors and windows or through attic vents. Lady beetles do not reproduce indoors during their hibernation period, and they do not harm humans or pets.

The best thing you can do for this problem is prevention. Caulk up all crevices around doors and windows. Make sure you have tight-fitting screens on windows and attic vents. You should especially concentrate on openings on the south and west sides of the house, because those are the warmer areas where lady beetles are more likely to gather. If you already have lots of beetles inside your house, about the only thing you can do is vacuum them up and dump them back outdoors, preferably in a sheltered place a long distance from the house. Avoid squeezing or crushing the beetles, because they can emit a fluid that can stain carpets or drapes. Spraying with insecticides is usually not effective, and trying to use enough insecticide to have some effect just adds a high level of toxic materials to your home.

The multicolored Asian lady beetle has probably been introduced into the U.S. more than once. Between 1978 and 1982 the U.S. Dept. of Agriculture released Asian lady beetles in Georgia and other parts of the southeastern U.S. in an attempt to use them as a natural control for pest insects on trees. However, those beetles disappeared, and none were seen for several years. Asian lady beetles appeared again in Louisiana in 1988 and are suspected of having arrived by hitchhiking on a ship docked in New Orleans. Since then, Asian lady beetles have spread throughout the eastern U.S. and eastern Canada. They were first found in Missouri in 1993 in Carter and Wayne counties, but have now spread throughout much of the state.