College News
College News

Lady beetles are swarming-- What should people do?

Lady beetles are swarming-- What should people do?

Lady beetles are swarming-- What should people do?

On a relatively warm, sunny afternoon this fall, don't be surprised to see large swarms of lady beetles looking for a sheltered place to spend the winter. Unfortunately, they often enter homes or buildings.

"This situation isn't limited to Kentucky. Lady beetles are looking for overwintering sites throughout the eastern United States this time of year," said Lee Townsend, entomologist with the University of Kentucky College of Agriculture. "As temperatures begin to warm up next spring, swarms of lady beetles will appear again as they leave overwintering sites."

Lady beetles enter homes or buildings through any kind of opening -- cracks, crevices, spaces around doors and windows, or where utilities enter the structure. The beetles can be various shades of yellow, orange and red. Some have up to 19 spots on their backs; others have no spots.

"They are a nuisance because they emit an unpleasant odor as a protective measure," he said. "When squashed, they produce a yellow stain that is fairly difficult to remove."

Townsend advised homeowners to exercise caution in any indoor pest control attempt, especially if they use aerosol bug bombs (total release foggers) to control infestations of lady beetles or other insects in homes and other buildings.

"The aerosol propellants used in foggers typically are flammable," he said. "It's possible to cause a fire or explosion by using an excessive number of foggers and placing them so large amounts of propellant have contact with an ignition source such as a flame, pilot light, or a

spark from an electrical appliance that cycles on and off, like a refrigerator or air conditioner. The Environmental Protection Agency recommends that the active fogger be placed at least six feet or further from all ignition sources. "

To reduce the likelihood of an accident, Townsend advised people to use no more foggers than necessary.

"Generally, one six-ounce or eight-ounce fogger is sufficient for an average-size home; smaller-sized foggers are available for apartments and other smaller units," he said. " Don't use foggers in small, enclosed places, such as closets, cabinets, or under counters or tables. Using no more than one ounce of product per 1,000 cubic feet of living area will reduce the chance of fire significantly yet still be effective."

(To calculate the volume of a living area, multiply the height, width and length of each room, and add the room volumes together. For example, an eight-foot by 10-foot by 10 foot room has a volume of 800 cubic feet.)

"Foggers have limited effectiveness because the insecticide only kills exposed pests that are hit directly with fogger particles," he said. "Particles of insecticide are not distributed into protected areas such as under furniture, in wall spaces, and beneath insulation in the attic. In addition, some people have the mistaken impression that the fogger fumigation will kill most if not all pests in the home or building. If used, this device should be part of a comprehensive plan to thwart persistent pests."

Consumers have several alternatives to foggers to control lady beetles, according to Townsend and Mike Potter, urban entomologist.

One option is to seal openings -- cracks, crevices and the like -- to prevent outdoor pests from entering the home or building.

Consider applying an exterior (barrier) insecticide treatment. Homeowners will get the most for their efforts by applying longer-lasting liquid formulations available from hardware and home and garden shops.

Apply the barrier insecticide with a pump up sprayer, hose end sprayer, or similar device treating at the base of all exterior doors, garage and crawl space entrances, around foundation vents and utility openings, and up underneath siding. It might be useful to treat the outside perimeter of the foundation in a two- to six-foot-wide band along the ground, and several feet up the foundation wall.

"Products found on Internet searches might not be labeled in Kentucky or might not be readily available to consumers," Townsend said.

Another alternative is to use the services of a professional pest control firm that has other control options.

Contact Information

Scovell Hall Lexington, KY 40546-0064