Eco-Cows Munch on Invasive Plants

  • Researchers are finding that Scottish Highland Cattle, such as these Rockhill Red Cows, have an appetite for many types of invasive plants. Photo courtesy of Marv & Ann Rockhill.

Cattle that love to eat thorny shrubs and nasty weeds are proving they can clean up areas infested with invasive plant species. The Great Lakes Radio Consortium’s Mary Jo Wagner has this report:


Cattle that love to eat thorny shrubs and nasty weeds are proving they can clean up areas infested with invasive plant species. The Great Lakes Radio Consortium’s Mary Jo Wagner reports.

For years, land managers have been trying to find better ways to control particularly troublesome plants. Invasive species such as multi-flora rose, prickly ash and wild parsnip used to be held in check by natural fires, or grazing by bison and elk. But ever since wildfires have been mostly controlled, and elk and bison populations have plummeted, many invasive species in the Great Lakes region have been growing out of control. So researchers have been looking for other ways to fight these invaders. At the University of Wisconsin, researchers have been testing Scottish Highland cattle on some fields containing invasive species. Consultant Martha Rosemeyer says the preliminary results look promising…

“One of the things we’ve found out by following the cattle is they really like wild parsnip when it’s young. Out of a field of grass they’ll identify and hone in on the wild parsnip and eat the whole patch of it.”

One of two farms testing the cattle’s weed eating potential is owned by Peter Rathbun. He says on one of the test plots, the parsnip was so high and thick, biologists wouldn’t go in to take samples.

“I was a little concerned, well are the cows going to go in and eat it and get sick, but they went in and ate it and they loved it.”

Rathbun has various weed and brush problems or “junk” as he calls it on 120 acres, including prickly ash, hawthorn, gooseberries and other plants that produce large thickets. He was one of the first farmers in Wisconsin to start raising the highland cattle several years ago and now has around forty animals eating weeds on half his farm. His goal is to return some o the land to its original oak savannah status. So far on his fifteen test plots with and without cattle, the results of grazing Scottish cattle are positive.

“It’s so wonderfully obvious what’s happening because here’s three strands of electric fence. On one side you can walk right through the woods…its no problem – you can see everything there. On the other side it’s dense, you don’t even want to think about walking through it. And this is only after 2 rotations.”

Rotating means moving groups of up to nine cattle around on once-acre test plots. The cattle spend two or three days on select plots each month throughout the summer. Martha Rosemeyer says researchers were interested in the breed of cattle because in Europe, they’re referred to as “eco-cows.” That’s because of their unique ability to eat plants that have inch-long thorns.

“They’ve got really tough tongues – they wrap them around these and pull – so they pull these things up like prickly ash leaves off and aren’t really bothered by thorns. They actually like thorns to rub and scratch…they’ll lean on things and scratch and they’ll break them and change the vegetation in that way too.”

Peter Rathbun says it didn’t take long for his cattle to tackle a patch of prickly ash after the gate into one test plot was opened.

“They ran over to it and started eating the actual bush. And I loved to see the reaction of some of the graduate students who’ve been working on this for a very long time. In their heart of hearts they really had some doubts whether the animals were really going to like to eat the junk.”

Once results are in by the summer of 2003, consultant Martha Rosemeyer says researchers may have a better idea of how effective the cattle will be at permanent eradication of unwanted plants.

“Certainly if you knock down a plant by taking off it’s above ground vegetation a number of times, it weakens the plant and it eventually will die. That’s what we’re hoping will happen but we’re not sure we need to test this and see the results…it’s speculation at this point.”

By comparison, Rosemeyer says on Department of Natural Resources land, a few test pilots were grazed and burned earlier this year to compare the weed control with the Highland cattle. It turned out that combination was too destructive and the burning was discontinued.

Meanwhile, not only do these animals eat through the bad stuff, but they also provide great hamburgers. Rathbun sells the meat as a low fat, very tasty source of protein.
For the Great Lakes Radio Consortium, I’m Mary Jo Wagner.