Iowa Insect Information Notes

Ladybugs in the Home - Asian Lady Beetle Traps

Ladybugs in the Home - Asian Lady Beetle Traps

The Asian lady beetle (Harmonia axyridis), is a common and widespread wintertime household pest across all of Iowa and most of the United States. Large numbers of these insects invade homes during the fall and remain active over the winter, especially in late winter when temperatures warm and days get longer. Ladybugs do not feed and cannot reproduce indoors; they have not multiplied indoors although it must seem that way to homeowners who have been inundated with them.

When lady beetles stranded indoors for the winter are emerging from inside house walls, there is no control option more practical or effective than repeated vacuuming. Spraying insecticides has little or no effect. However, one alternative for homeowners unable/unwilling to pursue wintertime ladybug control via vacuuming is the use of lady beetle traps as indoor collecting devices. Traps are not designed to kill lady beetles but rather to collect them for removal from the building. The traps use a light to attract the lady beetles at night. Black light bulbs work best, but incandescent light bulbs will also work.

Light traps can be purchased from companies that sell insect collecting equipment, or you can make your own. Basically what you will need is a light fixture with a funnel below it that funnels the beetles into a container from which they cannot escape.

A simple design for a light trap can be found online at Ohio State University Extension (http://ipm.osu.edu/lady/blt1.htm). See also our information on Asian lady beetles.

Updated 07/14/2005 - 3:03pm