As a youngster, do you remember singing, “Ladybug, Ladybug, fly away home…”, as a ladybug crawled up on your finger and flew away? Well, little beetle, if you haven’t flown away home by now, it may be too late as the temperatures have dropped into single digits in New England overnight. In the fall, these attractive little beetles of the Coccinellidae family seek out warm spots to hibernate, such as under debris outside or under bark on a tree but one particular variety often seeks refuge inside our homes.
The ladybugs we see inside our homes are the Asian ladybug (Harmonia axyridis). When temperatures drop, they will congregate on the sunny side of a home, favoring lighter color homes for some reason, where they seek out any crevice to hibernate. If a crack or crevice opens to the inside, then they will come right in… sometimes by the hundreds.
For years, the insects were introduced as an aphid and scale control in a number of states across North America. But the insects did not do well. They were found in Louisiana in 1988, some say from a Japanese freighter, and have expanded to much of the USA and Canada.
There are two good identifying characteristics of the Asian ladybug. First, the black markings on the head form the letter M (or the letter W, depending on whether we are facing the insect), and the legs are reddish. The adults can be a wide variety of colors from shades of orange to tan to red, some with many spots and others with spots that blend together as a black ladybug. The ones with fewer spots are usually male.
Although I can feel the small beetles occasionally nibble my skin when I hold them, the insects are not harmful to humans. They eat other insects so they have small chewing mouthpieces. The nuisance is the odor they emit and the yellow secretion they have when they are disturbed.
I have only seen a few of these beetles in New Hampshire, however, in parts of the country, it can be a mass invasion some years and other years not many at all. I can remember one year in Virginia, we had dozens entering through a window that didn’t shut properly. Solution? We swept them up, released them in the daisy patch where aphids lived, then simply sealed the crack.