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The Minnesota Department of Agriculture (MDA) has put together some tips to help prevent homeowners from becoming too annoyed by these beneficial insects.

The Asian lady beetle is a very beneficial insect that feeds on plant-destroying pests such as aphids and scales. In the Paynesville area, the harvesting of soybeans has forced the beetles to look for a new home. The beetles inhabit maple, walnut, willow, and oak trees, and is a particularly effective predator of aphids on pine trees, ornamental shrubs, and roses.

Sometimes called the Halloween beetle, the Asian lady beetle is easily identified by its bright-orange and black-spotted body. Individual colors can range from deep orange-red to pale yellow-orange.

Although the beetles help control plant pests, they can become a nuisance when cool autumn weather causes them to look for winter hideaways and gather in large numbers on homes and other buildings.

Asian lady beetles like this have started looking for a place to winter. The beetles frequently feed on soybean aphids and have been looking for a new home since the recent soybean harvest.

The MDA's Invasive Species Unit identifies and monitors insect pests in Minnesota to help protect the state's forests and plant industry. Section Manager Geir Friisoe said the Asian lady beetle population seems to be rising in Minnesota.

"Two years ago we saw a population explosion of these beetles," Friisoe said. "We think this increase could be related to increased aphid populations across Minnesota, because aphids are a major food source for the beetles."

Because Asian lady beetles cause no harm to humans and control pest insects, Friisoe advises homeowners to avoid killing them. Instead, he suggests the following tips to help minimize their nuisance level:

„Install tight screens and seal cracks and crevices around doors, windows, and siding. Common household items such as duct tape, steel wool, or caulk can be used to seal nooks and crannies that pests may use;

„Remove beetles from inside your home with a broom and dustpan or a vacuum cleaner attachment;

„Insects often enter homes through air vents. Put screens over these areas to deny them access; and „Don't kill the beetles by squashing them or by using insecticides and avoid handling them if possible. When disturbed they can emit an odorous, orange-colored liquid that stains walls and fabrics.

According to Friisoe, taking preventive action to keep insects out of your home is always a good idea because it reduces the need for pesticide applications.

For more information about controlling pests in and around the home, call the MDA pest hotline at 651-296-6684 or visit the MDA website at www.mda.state.mn.us.

(Source: the Minnesota Department of Agriculture)