LUNDBRECK, Alta. — Cattle ranchers traditionally aren’t keen on sheep but the “range maggots” they sometimes disparage have brought a major weed problem to heel on southern Alberta’s Waldron Ranch.
Several years ago, leafy spurge flourished on parts of the ranch, turning the prairie greenish-yellow with its blossoms and foliage. Leafy spurge chokes out native grasses, spreads quickly and is difficult to control.
Today, the Waldron’s area most affected by leafy spurge has been reclaimed by the rough fescue that makes cattle grazing possible for 10 months of the year.
Ranch manager Mike Roberts remembers when he first pitched the idea of using sheep to manage the weed problem.
“I wasn’t really scared of sheep because my parents had had sheep ever since I was a little kid. I kind of grew up with them. But of course the Waldron was made up predominantly of ranchers and had been ranchers for four generations.
“They hated sheep. They weren’t quite sure why they hated sheep, but they hated sheep.”
But with leafy spurge taking over cattle grazing land, members of the grazing co-op agreed to give sheep a try for one season. They made a deal with the nearby Livingstone Hutterite Colony to graze a flock on the Waldron.
The colony pays 20 cents per day per ewe and the grazing co-op uses that money to pay a herder.
“We can achieve good control now in three months, June, July and August.”
Roberts said it takes about a year to train sheep to eat spurge but once they learn, a flock can be fairly easily guided to weedy areas.
“Sheep are very particular eaters and they like anything that’s leafy and high protein, high nutrition, so they selectively graze the leafy spurge, three-flowered aven, lupin, all the forb type plants and they’ll walk right past the rough fescue,” said Roberts.
He said grazing co-op members were initially worried the sheep would graze the pastures “down to the linoleum” but with herding management and the sheep preference for leafy plants, that hasn’t been an issue.
In fact, once the spurge has mostly been eaten, the sheep become harder to herd because they are searching for more weeds to eat.
Roberts said the arrangement between the colony and the Waldon Ranch has benefited both parties. The sheep gain weight over summer and gain condition because of the constant movement. Roberts said the colony has won awards for wool from the sheep because of its cleanliness and consistency.
“It’s been a win-win for us. It’s been really good for the Waldron because the funds that were going every year to leafy spurge (control) can be diverted to other projects on the ranch.”
The sheep also help spread spurge-eating beetles that were introduced as a biocontrol measure.
“They eat at the root system and they also eat at the plant leaves in the summertime,” Roberts said about the beetles, noting the insects hitch rides on the animals’ wool.
“They are extremely slow to get established, but we found that once we had the sheep here and the sheep were weakening the plants, then the beetles just took off. The sheep are always grazing the leafy spurge and so we’ve spread those beetles up and down the valley. The sheep and the beetles work together.”
The sheep are penned at night during their grazing season, using electrified netting, to protect them from predators. The night pens are moved every few days, which results in parts of the pasture getting manure fertilizer.
“I have never seen a leafy spurge plant growing in (a night pen site) because of the manure, because there’s not very much gets through a sheep, and most of the leafy spurge is consumed before it’s in the seed stage anyway.”
Roberts said the key is to get the same sheep back to the ranch year after year, so experienced spurge-eating ewes can teach others. Breed is also a factor in containment.
“We like to get the Rambouillet sheep because they’re not too brilliant and they won’t crawl through the seven-wire barbed wire fence. There’s other breeds of sheep that will figure that out in about an hour but the Rambouillet, they don’t.”