Ladybugs didn't come from helicopters
University of Tennessee Extension agent John Teague said that, contrary to one recent rumor, the current bumper crop of lady beetles was not dropped from helicopters by farmers.
"They've been here for years and years," said Teague. The ladybug-like Asian beetles do, in fact, help agriculture by eating aphids. The species was brought to the U.S. many years ago with that in mind, and homeowners can buy them in small quantities for release. But this year's unusually-large numbers have do do with weather, not with any sort of human intervention, said Teague. Crops, vegetation and moisture have been ideal this year, meaning that aphids -- including the asian wooly hackberry aphid, the mysterious white bugs seen here several weeks ago -- have been plentiful. And since the lady beetles feed on aphids, a bumper crop of aphids leads to a bumper crop of lady beetles.
The onset of cold weather causes the bugs to seek warmth -- such as that provided by occupied buildings. According to Teague, the bugs tend to swarm just after a cold snap. They are attracted to light-colored buildings with vertical lines, which they read as being cracks or crevices in which to hibernate. When they can't find a crack, they keep looking, eventually finding their way into the structure.