<< Back 11/27/02 Organic gardeners invade households By Joan Petit Aphids beware! Homeowners, take cover! Fall brings a series of unpredictable but inevitable events to Western North Carolina: the changing of the leaves, the season’s first frost, and, more frightening than any Halloween specter, swarms of Asian ladybugs. Like something out of a Hitchcock movie, the ladybugs arrived in swarms. A recent Sunday morning was the worst day in my neighborhood. The ladybugs massed first at the sunny south and west sides of the house. It was a nice day, and, thinking I had outsmarted them, I flung open the east-facing doors, to let in some fresh air. Twenty minutes later, mobs of ladybugs were crawling all over the inside and outside of the glass doors. I shut down the house, and, with lips pursed, dashed out of the house only when absolutely necessary, opening and closing the door as quickly as possible. As the ladybugs buzzed around, my puppy snapped at a few, and then sprinted to the water dish. She refused to eat any more afterwards, thus eliminating one potential solution. A cursory web search turned up many shrines to ladybugs, but few helpful tips for dealing with infestations. Revered by gardeners and bug-lovers around the world, these little bugs are quite popular. Yet, I now cringe every time I see cutesy country kitsch decorated with the dreaded ladybug and recall only vaguely my childhood fondness for these spotted insects. Their popularity, however, is the result of their voracious appetite for aphids. This talent inspired the U.S. Department of Agriculture to import them from 1978-81, according to Christy Bredenkamp, the Cooperative Extension Agent in Horticulture for Swain and Jackson counties. For just a few years, the multi-colored Asian lady beetles (as they are properly called) were brought from Japan to pecan orchards in Georgia and to other crop fields in Louisiana, Mississippi, Maryland, Connecticut, and Delaware. Their population grew over the next decade, and 1992 saw the arrival of this non-native species in Western North Carolina. The ladybugs that I recall from childhood were a native species. Though some of the American beetles over-winter, they do not swarm, and they tend to prefer tree trunks and rocks for hibernation. Back home in Japan, the Asian ladybugs winter in banks and cliff faces with white rocks. As the days shorten and temperatures drop, a biological cue sends the insects towards bright, reflective surfaces. In Japan, this drives them to the cliffs; in the US, it sends them swarming into sunny houses with lots of windows. Bredenkamp says that the swarming usually lasts for three weeks and ends when temperatures are consistently cold. Sealing the cracks around doors and windows keeps many of the bugs out. Once they venture inside, Bredenkamp recommends vacuuming the bugs if you have fewer than 100 invading daily. For folks with upwards of 500, she recommends buying or building a special trap with a black light that attracts the ladybugs. For truly infested homes —those with upwards of 1,000 ladybugs — a flea bomb is another possibility. When my husband and I first moved into our newly constructed home three years ago in January, we had to contend with these winter hibernators immediately. They were everywhere. At work, I’d find them in my purse, having hitched a ride from home. We flea-bombed the house, desperate for a solution. That same day, we had to vacuum three times over a bug-covered floor, and daily vacuums for weeks after that could hardly keep up with all the dropping ladybugs. The next fall, when the newest crop of ladybugs swarmed to our windows, my husband and I found a commercial website advertising an insecticide with cypermethrin, which the sellers claimed would repel the ladybugs. We bought the insecticide and the pump, and each year since have applied this toxic product to the outside of our house. The results have been significant: no return of the ladybugs until the following year. When I asked Bredenkamp about this product, she said that she hadn’t seen similar results with other insecticides, which usually kill on contact but do little to repel further insects. So the jury is still out on whether this product would work for other homes in Western North Carolina. The irony, of course, is that these bugs were imported to be an organic solution to a major pest problem. In fact, their talents are so appreciated that gardening catalogs sell these bugs as an organic alternative to pesticides. As a committed organic gardener who eschews fertilizer and pesticides anywhere on our property, and especially in the vegetable garden, I appreciate their summertime appetites, as they devour aphids and other tomato-destroying pests. Based on the sheer volume of ladybugs, I can’t imagine there’s an aphid living within miles of my house. Yet, as with kudzu and other exotic species, the ladybug population has exploded. They have no natural predators and no apparent population control. And now, at my house, we’ve been driven to use a toxic chemical to keep this organic savior away. Despite the annoying swarms, however, the lady beetles will not actually attack you. They don’t bite, though they do have spines on their legs that can irritate sensitive skin and feel like a bite. If squashed, they’ll stain painted surfaces, and they’ll stink up your vacuum bag if you don’t change it. Fortunately, the ladybugs will leave your house eventually. In the spring, when they see the green outside, another biological cue pulls them out of the house and onto the green leaves of trees, where they mate and lay eggs. They live to be three years old. One final interesting tidbit I learned from Bredenkamp: each bug has from zero to 20 spots, depending on a few factors — age, genetics, and elevation. Our now-local mountain varieties tend to have more spots. For information on how to make a lady beetle trap, or where to order one, contact Christy Bredenkamp at the Swain or Jackson County Extension Service, at 488.3848 or 586-4009. (Joan Petit is a writer and teacher who lives in west Swain County. She can be contacted at joanpetit@earthlink.net)