Remember the man-eating plant in “Little Shop of Horrors?”
Fiction meets fact as the invasive kudzu plant advances from the southeastern U.S. to Canada. You’ve seen it smothering bushes, trees and even abandoned homes along highways. It might also be sneaking through local meadows, woods or climbing garden fences.
Kudzu can grow one foot per day and up to 90 feet in a single season. It throttles native species, including trees, which are girdled by the vine, broken by its weight or killed by lack of light.
Kudzu also produces isoprene and nitric oxide, which, when combined with nitrogen in the air, form ozone. Ozone irritates the eyes, nose and throat and can damage the lungs, sometimes causing asthma or worsening asthma symptoms. As a mutagen, it can cause lung cancer. Ozone also hinders the growth of many plants, including crops grown for food.
What should you do to save your property from being swallowed up? Here are several methods of control. Whatever you decide, do it right away. The longer kudzu occupies a piece of land, the harder it is to stamp it out.
You can’t cut kudzu and expect it to go away. You have to kill or remove its root crown and all rooting runners. When you dig up crowns and nodes, wrap them in plastic before disposing of them. If dumped in soil, they’ll start to grow again.
If you see kudzu on your lawn, you can mow it down. Continuous mowing depletes the plant’s energy reserves, although killing it takes time. Strip vines from trees and bushes. In flower beds you may want to cover kudzu with heavy plastic to smother it.
If you have a large property with livestock, allow them to graze on the vines. Absent livestock, you can use a tractor with a rock rake to pull as much of the vine out of the ground, then hand-pull the rest.
Kudzu might succumb only to chemical attack. Only a few herbicides work – none of them “green.” In non-crop lands or areas with little human or animal interaction, look for products containing Triclopyr. Cut the vine stem, then paint the herbicide directly on the new cut.
You can also kill kudzu with glyphosate-based products, which kill all plants they come in contact with, so apply them directly to the cut vine stem.
Kudzu is a threat to us, especially if we continue to experience mild winters. Learn to identify it and eradicate it. Report new appearances to county and state authorities so they can monitor its progress and stop its spread.