WOOSTER, Ohio – An invasive species synonymous with the South has taken root in the Eastern Corn Belt, but according to Ohio State University Extension field crop pathologist Anne Dorrance, it doesn’t yet present quite the headaches for farmers above the Mason-Dixon Line as it has below.
“I first became aware of this plant back in 2005 when we started getting an assessment of how much kudzu was around and how close it was because it is an additional host of the soybean rust pathogen,” said Dorrance, who is also a soybean disease researcher at the Ohio Agricultural Research and Development Center.
Dorrance said in her studies of soybean rust, she traveled extensively in southern Ohio searching for patches of kudzu, learning how the plant overwintered in the relatively colder climate of the Buckeye State.
What she learned over the past six years, coupled with the work of other soybean disease researchers across the country, is that not all kudzu is hospitable to soybean rust.
“One of the discoveries of this multi-state soybean rust came from scouting kudzu patches in the South where rust has appeared every year,” Dorrance said. “As it turns out, not every patch of kudzu is a good host for rust. Some patches never seem to develop rust, and that wasn’t known when all of this research started.”
The plant, native in Japan and other East Asian countries, was first introduced into the U.S. in the latter half of the 19th century. Considered an invasive species here, it commonly covers roadsides and other expanses of the southern U.S.
Dorrance said while the plant isn’t a major concern yet in terms of serving as a host for the rust pathogen in Ohio, it could be a concern for other production-related issues.
“One of the concerns that came up more recently is that some of these newer insects and pests that like soybeans also like kudzu,” she explained. “That’s now one of the secondary issues to come from our study of the plant.”
Moreover, given the relatively rapid proliferation of the plant in the South, Dorrance and her colleagues at Ohio State agree it is important to keep kudzu from taking root, literally and proverbially, across Ohio.
“It’s a weed that in the South has completely overtaken things, so our recommendation will be not to let it do that,” said Mark Loux, Extension weed specialist. “It is an invasive weed so we want to keep on top of it from that standpoint.”
Dorrance agreed with Loux that keeping tabs on kudzu is critically important, particularly in keeping the plant from destroying the native habitat of other plants, especially those that are endangered or rare native plants.
In her early research on kudzu, Dorrance worked with foresters with the U.S. Department of Agriculture’s National Forest Service to scout kudzu in Lawrence and Adams counties.
“I worked with a forester at the forest service research station and we traveled around Portsmouth, and right there near the Ohio River behind a bunch of houses is a big hill that was really, really thick with kudzu,” she recalled. “It gave me a sense of how big the vine is. It is becoming established down there, and it’s wiping out habitats for some endangered plant species, so that has become a concern over the past few years.
Dorrance said management is important, but Ohio’s climate will help.
“It does freeze back, and so keeping a monitor on where it grows is important,” she explained. “I don’t think at this point we want to spray, though.”
She said at one point the Forest Service employed goats as a management strategy in those areas that were critical to protect for endangered plant species. Farmers in the South have used various methods to control or eradicate the weed over the past several decades, with mixed success.
“In areas where we have an endangered plant species, we should be trying to manage it as much as possible. Unfortunately, with all these new invasive species, learning to live with them and learning to manage them is really what we need to do.”