Scientific Name: Harmonia axyridis
Accepted Common Name: Multicolored Asian Lady Beetle
Other Common Name: Japanese Lady Beetle
Control of this Beetle in Houses
Multicolored Asian Lady beetles enter the house through small openings around windows, doors, and utility access points. In addition, they can enter the house by cracks in the siding and trim and through attic vents. Sealing those entry sites is the best method to keep them from becoming indoor pests later. Conduct a thorough energy audit of your house, as places where cold air can enter the house are places where this lady beetle can gain access. Fill all cracks and leaks with a fine quality silicone or silicone-latex caulk.
Once inside, insecticides are not recommended except for severe cases. Sweep up with a broom and dust pan all beetles that collect in window sills and on walls. Beetles can also be picked up with a vacuum cleaner but bags will need to be discarded so that beetles do not escape.
Control Check List:
- Seal windows and doors with weather stripping
- Check attic and basement for possible entry sites
- Check utility and pipe access points to the house
- Check window screens
- Seal cracks and crevices created by house siding
- Use vacuum cleaner to pick up beetles
- If spraying for beetles inside, pick up dead beetles with vacuum cleaner
- Seal between logs if residence is a log home
Beetles typically start moving into houses and have a peak of activity on or just after October 15th in Virginia. They are quite active on warm days in the fall and winter but have a second peak of activity in late March as they attempt to work their way outside. They do not mate or reproduce in the house and typically overwinter in the walls. They work their way into the living quarters in an attempt to get out of the house. The heated portions of the house are simply too warm and dry for these beetles, and they die out in a few days.
After exiting the house or protected overwintering site in the spring, the beetles seek trees that have populations of aphids on the bark or on the leaves. The adult beetles feed on the aphids and then mate. Bright yellow eggs are laid in clusters on the bark and 3-5 days later hatch. The newly hatched larvae that resemble little alligators take 12-14 days to reach maturity. They then pupate and the adults emerge in about a week. In cool weather, development can take 36 days or longer. The adult under optimal conditions can live 2-3 years.
History of the Beetle In Virginia
This beetle was first detected in Lee County, Virginia, in January of 1993. By fall of 1993 approximately 40 counties, covering all geographical regions of the state, had new county records. By the late 1990's it was not only statewide in distribution but also covered much of the United States as well.
History of the Beetle in the United States
The multicolored Asian lady beetle was first recorded as a pest in houses in 1988 in Abita Springs, Louisiana. Prior to that time it was released many times between 1916 and 1985 as a potential biological control agent by the USDA in Georgia and Alabama. In those trials the beetle was not recovered after the release, so it was assumed that it had not established and was incompatible with North American conditions. The source of the original infestation in Abita Springs, Louisiana, is unknown. The original infestation site in Louisiana is close to ports used for international shipping, including cargo containers from Asia.