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It’s been called the “vine that ate the south.” Kudzu grows so fast it can completely cover a cabin in the woods in a couple of days. The invasive plant takes over another 150,000 acres every year. Which costs another $6 million to control.
But plant pathologists with the U.S. Department of Agriculture’s Research Service have gotten promising results with a fungus that itself rapidly spreads in kudzu. The fungus is called Myrothecium verrucaria. In early tests, the fungus killed all kudzu seedlings and at least 90 percent of older plants. Most important, Myrothecium did little or no damage to the species that commonly live in habitats infested with kudzu, such as pine, oak, cedar, pecan, hickory, blackberry and, of course, sassafras.
So what’s the catch? The fungus produces chemicals called tricothecenes, which can damage the health of humans and animals. But the researchers discovered that if they grew the fungus in a fermenter or on a liquid diet, the production of the toxins fell precipitously. If the fungus can be safely let loose one day, it could finally give kudzu the heave-ho.
—Steve Mirsky