2004 Year in Review

Lady Beetles search for warmth in your home

Since the late 1990’s, the multicolored Asian lady beetles (Harmonia axyridis) have created a not-so-positive name for themselves in the fall. Although they are beneficial creatures that help farmers control soybean aphids, their sheer numbers create headaches for homeowners.

Multi-colored Asian lady beetles (sometimes called Halloween ladybugs) range from orange-yellow to bright red-orange. The number of spots on their wings varies from zero to more than 20, though higher numbers are the most common. The combination of colors and spots yields about 50 different appearances for the same species. Adults can live up to three years.

Lady beetles are cold-blooded creatures that search for warm spots to spend the winter. Many will congregate on the south side of trees or barns, often burying themselves in cracks, crevices and under piles of leaves. It appears that they release a pheromone or insect hormone that attracts other lady beetles to the same area.

Lady beetles will squeeze through tiny cracks and crevices around windows, doors, utility pipes and loose siding to enter homes. Dark-colored homes aren’t as prone to insect invasion as white or light-colored ones.

Once inside, they tend to congregate on southern or western walls and windows for warmth. More than likely, the homeowner only sees a fraction of the creatures that are over wintering between the walls.

Asian lady beetles do not reproduce indoors. They will bite if disturbed, though like most spiders, they don’t go out of their way to bite. If the beetles are significantly disturbed or threatened, they will ooze “beetle blood” from their leg joints. This foul-smelling liquid is not considered toxic, but it can stain fabrics such as carpets, upholstery and drapes.

If lady beetles are a nuisance at your house, try these control methods:
- The insects first find a warm spot on the south or west side of the house. So, caulk cracks and crevices on these sides of the house. Make sure doors and windows close tightly. Avoid leaving windows open on warm autumn days, especially if screens are not tight. If siding is loose, secure with nails.
- Caulking is the first and major source of control. Caulk around window and door frames. Check for gaps around utility pipes, wires that enter the house, and electrical outlets, and caulk if necessary.
- University of Illinois Extension does not recommend insecticides for beneficial insects, though several products are available. Contact a professional exterminator to apply a pyrethroid-based barrier on the outside.
- When you do find insect indoors, suck them up with a vacuum cleaner. You might just consider keeping the vacuum out for the next month as the beetles work their way into rooms. Empty the bag regularly. Once the temperatures turn extremely cold in December, the number entering rooms of the house will drop drastically.
- Remember that lady beetles stain when crushed. So, a regular broom or rag may not be the best bet.
- Multicolored Asian lady beetles are attracted to “black light traps.” The trap is basically a collector bag placed under a black light bulb. The beetles fall in the trap and cannot escape. They aren’t killed, so they can be relocated outside.

The lady beetle is a nuisance, but not dangerous to humans, pets, food or household items. The University of Illinois does not recommend using a chemical for indoor control.

by  Editor, theCity1.com
November 23, 2004