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Teaching Cows To Eat Weeds

published: September 29th 2008
source: Prairie Star

ALDER, Mont. - Cattle grazing can provide efficient and effective weed management alternatives to chemical control when trained properly, according to trainer Kathy Voth of Livestock For Landscapes.

“It is cheaper, more efficient and just as effective as herbicides,” said Voth of Loveland, Colo., who trains ruminants to graze on weeds.

Voth recently trained 320 head of cattle and 38 bison in Madison County, Mont., to dine on Canada thistle as part of the “We'd Eat It!” project sponsored and coordinated by the Madison Valley Ranchlands Group's Weed Committee and the Natural Resources Conservation Service.

“We are always looking for more cost effective tools for managing noxious weeds,” said Melissa Griffiths, project co-ordinator. “As prices for fuel and chemicals continue to increase, it makes sense for us to solve our weed problems by turning all our cattle into weed managers.”

The Madison County cattle and bison are now grazing their pastures looking for Canada thistle in addition to other forages.

“The thistles don't harm the cattle,” said Voth. “I have trained a lot of cows to eat Canada thistle and pricklier thistles as well, like the Italian thistle in California that has half-inch spines. Cattle have eaten the weeds with gusto and have developed no sores of any kind.”

Training ruminants to eat weeds isn't as easy as spraying molasses on the weeds. It takes planning and knowledge of the animals' dining behaviors.

Voth studied animal behavior when she worked for the Bureau of Land Management at Utah State University.

“I was researching using goats for resource management for fire control,” she said.

Then, in 2004, Voth teamed up with the Grant-Kohrs Ranch National Historic Site in Deer Lodge, Mont., to put together a pilot project to train cattle to eat Canada thistle, leafy spurge and spotted knapweed.

She has trained cows in Montana, California and Colorado to include a variety of thistles, knapweeds and mustards in their diet.

“For less than $200 in materials and ten to twelve hours of my time, I can teach about 50 cows to eat a new weed,” said Voth. “Then, they will teach their calves, and they'll teach their herd mates, and at that point we have a whole weed-eating army going out there.”

Before the training commences, Voth said she always makes sure she knows the weeds to be consumed.

“You need know what is in the weed,” said Voth. “All plants contain toxins, and if the dose of a toxin is high enough it can cause harm to animals. Before deciding to train an animal to a weed, I always check toxin contents to ensure that animals will not be harmed.”

Like most forages, weeds can be quite nutritional early in their growth and lose nutritional value as they grow older. Voth said all the cattle in her program have actually gained weight at rates equal to or better than cattle not grazing weeds.

“Canada thistle's nutritional value is the equivalent of alfalfa,” she said. “Other weeds I have fed to animals have nutritional values equal to or better than alfalfa. That's why the animals eat them.”

Research has shown that animals will choose to eat based on the feedback they get from foods, said Voth.

“Good nutritional value means that if I can get them to try it during training, they will continue to eat it in the pasture,” she said. The next step to training animals to eat weeds is to select healthy herd animals most likely to try new foods.

“The young animals are more likely to try new foods,” said Voth. “However, I have found working with cow-calf pairs effective. The calves learn pretty fast.”

In the first four days of the training, Voth said she feeds the animals their normal ration and supplements with different feeds, such as cubed alfalfa, wheat bran and rolled corn.

“I get them used to the idea that food can look and smell in a whole variety of ways,” she said.

On the fifth day of the training, Voth introduces another new food - a weed - to the animals' plate.

“I skip the morning feeding so they are excited to see me,” she said. “I mix the weeds with a familiar food, and feed them. Animals will try something new if it has something familiar with it.”

Voth mixes the weeds and familiar rations for two days before feeding just plain weeds. Then, she puts the animals out to graze in a small pasture where normal forage is mixed with weeds selected for the training.

“After a couple of days, they usually get the hang of eating the weeds - wrapping their tongues around that new plant, eating something that is maybe taller than what they are used to,” said Voth. “Then, I'll put them in another practice pasture before I turn them out to the big pasture.”

Once they have learned to eat weeds, cattle can “teach” other non-weed-eating herd mates how to eat weeds.

“In 2007, I had 12 trained heifers that we turned out with 120 untrained cattle for 30 days, and they are all continuing to eat the weeds today,” said Voth.

After completing their training, the trained cows and bison in Madison County are now grazing their pastures, searching for thistle, and teaching other ruminants the same skill.

Alder, Mont., rancher Steve Wood said he noticed his steers that pasture next to his trained heifers also started eating Canada thistle.

“Even if they don't eat it all, they're eating 200 percent more than they did,” he said. “I'm tickled.”

In addition to Canada thistle, Voth also taught cattle to eat musk thistle and spotted knapweed during the “We'd Eat It!” project.

“It was easy and fun,” said Brett Owens of Owens Ranch in McAllister, Mont., whose herd of 21 head learned to eat musk thistle, Canada thistle and spotted knapweed.

Madison County rancher Craig Woodson said he sees the potential to make additional profit from his small herd of Canada thistle-eating heifers.

“It's possible we could rent them out to neighbors who have weed problems on small acreages but have no cows of their own,” he said.

Marni Thompson, district NRCS conservationist for Sheridan, Mont., also sees potential for growth in the “We'd Eat It!” project.

“We are truly excited by the results of this project and will incorporate the technique as part of our conservation planning efforts throughout Madison County,” she said.

This year's “We'd Eat It!” project was funded through a Conservation Innova-tion Grant from the NRCS.

“NRCS was an invaluable partner on this project, providing local leadership as well as technical and field assistance,” said Griffiths. “We're looking at additional funding opportunities as a way of adding core ranches and a monitoring component to the project next year.”

The Madison Valley Ranchlands Group's weed committee was formed in 1999 to address invasive plant concerns in the Madison Valley.

Committee members work to promote noxious weed awareness and education through a variety of projects and partnerships, said Griffiths. The committee also facilitates on-the-ground projects by working

For more information about training ruminants to eat weeds, check out the Web site at www.livestockforlandscapes.com or e-mail Voth at kvoth@livestockforlandscapes.com.