By Lew Holloway,
WVU Extension Agent
 It seems like only yesterday that they left, but again this year, the Multicolored Asian lady beetle has returned. Released by the U.S. Department of Agriculture in Louisiana and Mississippi in 1979 and 1980, the beetles have become well established in the South, Northeast, Midwest and as far west as Oregon.
Officially identified as Harmonia axyridis, the Asian lady beetle comes in many color combinations. They range from pale yellow-orange to bright red-orange and come with or without black spots on the wing covers.
Outdoors during the growing season, Asian lady beetles are quite beneficial. As predators of aphids associated with trees, shrubs, ornamental plants, and some agricultural crops, they are reported to be better than native lady beetles. They are not poisonous or otherwise harmful to humans, pets, or property. However, the mere presence of such large numbers inside homes can be a major nuisance. This lady beetle does not carry disease, but it will bite in rare cases.
It is believed that females over winter unmated in protected sites, with the majority of the population mating later in the spring. In cool spring weather, development from egg to adult can take 36 days or longer. After emergence, adults can live as long as two to three years under optimal conditions.
The challengeâ¦how to keep the beetles out of the house! The beetles enter through small openings around doors, windows, and utility access points. In addition, they can enter through siding gaps, cracks, and attic vents. Sealing those entry points is the best method of keeping them and other pests from entering the home. Use a high-quality silicone caulk to seal all cracks.
After the beetles have gained entry, the use of insecticides is not recommended, except for severe cases. To remove beetles in the home, use either a broom and dust pan or a vacuum cleaner. When using the vacuum, be sure to change the bag to prevent escape of the collected beetles.
A new low-cost window trap for daytime catches of lady beetles is being developed and tested by WVU researchers. Preliminary results showed that the trap is effective during daytime, when room temperature is high enough to allow enough lady beetle activity.
A new homemade light trap also has been developed by Ohio State University, which uses items found at home or the local hardware store (e.g., clamp light, a 60-watt incandescent bulb, twist ties, transparencies or plastic report covers, 2-gallon plastic milk containers with caps, and black paint). This trap is effective and very inexpensive. For a diagram and assembly instructions, visit the Ohio State University at
www.ag.ohio-state.edu/~ipm/lady/blt1.htm.
Another suggestion is simply to be patient. Reports indicate that the beetles, after settling down on the sides of houses, often leave on their own in a few days or weeks.
For additional information visit www.wvu.edu/%7Eagexten/ipm/insects/beetle.htm or contact the Calhoun County Extension Office at 354-6332. This article is based on the research of John F. Baniecki, M. Essam Dabaan, John Freeborn, Bobby Cheves, and David Richmond.
* Programs and activities offered by the West Virginia University Extension Service are available to all persons without regard to race, color, sex, disability, religion, age, veteran status, political beliefs, sexual orientation, national origin, and marital or family status.
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