The Kudzu of the North

  • Vern Stephens wrestles a strand of dog-strangling vine. It's part of his job to spray a targeted herbicide on the invasive plant to kill it. (Photo by Rebecca Williams)

If you’ve ever lived in the south, you know kudzu. It’s an invasive plant that grows like crazy. Covers highway signs and telephone poles and anything that doesn’t run fast enough. There’s a plant in Michigan that’s getting a little crazy too. It’s not kudzu-crazy yet, but experts say we need to get a handle on it.

It has a memorable name: dog-strangling vine.

Pictures of the plant

A Wiki post on the plant

More from the invasive species atlas


It’s also sometimes called swallow-wort.

I’m on Michigan State’s campus and I’m here with Vern Stephens. He’s a senior wildlife assistant with the Department of Natural Resources and Environment.

Rebecca Williams:We’re out here so you can show me this stuff. Does it live up to its name?

Vern Stephens: Yes, it does. It’s a horrible plant. In fact if we look at it a little more we’ll see it’s actually a series of ropes and vines that entangle upon themselves, and if we try to walk through it we won’t get very far.

(sound of Stephens pulling on vine)

And you can see the rope that’s formed, it’s growing up this high bush cranberry. But you can see that the plant is easy to identify if you know what it looks like because it’s a very glossy leaf. It stands right out and it’s very waxy. It can go anywhere. It can adapt. And on some of the sites it was only a small patch for five years. And then the plant acclimated. And then it exploded. And now it’s taken over 20 acres of woodlot. When we say taken over, it’s at least chest high. Vines that look like this inch think rope everywhere. You can’t even walk through it. So it makes it very difficult.

RW: Before you pointed this out to me, I wouldn’t have known what it was. It just looks like any other Michigan plant.

VS: Right. And that’s the problem. This actually is a plant that becomes a biological trap for monarchs. They go to it because it’s in the milkweed family. And then lay their eggs on it and either the eggs don’t hatch or the butterflies, the caterpillars, die, because it’s toxic to them. Nothing feeds on it because it’s toxic to cattle. It’s toxic to horses or any animal that grazes on it. So if it gets into a pasture it becomes a problem.

RW: How long has this plant been in Michigan and how did it get here?

VS: We don’t know exactly how long it’s been in Michigan but back in the 1850’s is when it came to the United States. We suspect it was brought in through botanical gardens and escaped. It doesn’t take very many pods to all of a sudden populate an area.

RW: So we see pictures of kudzu in the south where it’s covering trees, telephone poles, cars…

VS: That’s what this looks like in Springfield Township. On the corner of Davisburg Highway and Dixie Highway. It’s just columns. Going up the guide wires to the poles, going up the trees, covering the trees. It’s unbelievable.

RW: How widespread could this get in Michigan?

VS: If it’s made it to Petoskey and it’s on the west side of the state, we’ve found some in Grand Rapids, and it’s on the southeast side of the state, it’s just a matter of time before it’s everywhere. If we don’t do anything at all. I’m not convinced we don’t have populations in the UP. I don’t know that we’re on top of it, but I know we have a good idea on where it’s at and what its capabilities are.

RW: Vern Stephens is a senior wildlife assistant with the wildlife division of the Department of Natural Resources and Environment. Thank you very much.

VS: You’re welcome.

RW: If you want to find out what dog-strangling vine looks like, you can go to our website, environment I’m Rebecca Williams.