WASHINGTON – A foreign invader is digging into American soils, and it’s snaking its way north; closer, and closer, to Iowa.
“It’s just one of those really nasty vines that literally grows almost a foot a day under proper conditions,” says Lewis Ziska with USDA’s Agricultural Research Service. That’s one reason he calls kudzu one of the most invasive weeds in North America.
Kudzu is native to Southeast Asia, where it’s found in parts of China, Japan and Korea. It grows in places where other things don’t, which is why it was brought into the United States in the first place.
“It was actually brought over in 1876 for the Philadelphia exposition,” says Ziska, “as a showcase for the new wonder plant that could be planted anywhere, and control erosion, and would make a nice, uniform green background.”
It did all of that, but perhaps too well. In the early 20th century, the Soil Erosion Service, which was the precursor to USDA’s Natural Resources Conservation Service, recommended kudzu cover to mitigate erosion. Kudzu was popular in the southeast, where it grew unimpeded and gained its reputation as the “vine that ate the south,” and now Ziska says taxpayers are footing the bill.
“The U.S. probably spends on the order of $50-$60 million a year just trying to control Kudzu for public infrastructure; utility companies spend millions of dollars every year to control Kudzu off of power lines and other structures, let alone what it does in terms of farming or cases of biodiversity.”
Kudzu is a known host for soybean rust. That wouldn’t be such a problem if it were confined to the South, but it’s spreading north and west.
“It was reported in Canada a few years ago, and it’s prevalent throughout Michigan, Ohio, Indiana, Illinois, and parts of the Northeast, and recently, showing up in Orgeon and Washington state.”
The old adage that life’s lemons should be converted to lemonade rings true in the case of kudzu. Ziska says vehicles could actually run on the creeping vine, and there’s not exactly a shortage of it.
“One of the potential positive benefits of kudzu is that the roots of kudzu are very high in starch,” says Ziska, “and it may be a potential biofuel. And the USDA, working with the University of Toronto and Auburn University, has looked at the biofuel potential of kudzu roots. Now, obviously not every batch of kudzu can be harvested, but in areas where it’s growing on abandoned farmland, for example, or in flat areas, where it can be looked at and harvested fairly easily, then we think there’s a potential there for making as much ethanol, bioethanol, from an acre of kudzu as you could from an acre of corn. In fact, we think there’s actually more ethanol that could be converted from kudzu than can be converted from corn. So, while we’re not advocating, of course, for anybody to plant kudzu; we don’t want that, but what we think we could do, is to take the existing kudzu and convert that to a biofuel. That’s sort of a win-win.”
Susan Carter with the U.S. Department of Agriculture contributed to this report.
To hear more about how kudzu threatens Iowa’s soybeans, click on the audio player above this story.
