Nature's Weed Eater
A unique approach to controlling invasive species.
Sixteen hundred and eighty hoofed feet clacked across the Drinking Horse Trail bridge spanning Bridger Creek. Urged on by two border collies belonging to Alex, a herder from Peru, the river of 420 goats headed for invasive leafy spurge thickets on the hillsides along the trail. A Great Pyrenees guard dog surged along with them, always staying just to the outside of the herd.
I ambled along behind them with Lora Soderquist, who works with Prescriptive Wildlife Services to help manage not only leafy spurge, but other vigorous noxious weeds that are overtaking hillsides here in Bozeman, and around the West—as far away as San Diego.
“Why goats for this job?” I asked Lora, as she and Alex called out commands to the dogs, which dutifully moved the goats through the brush.
“They mimic the historical herd movement of pre-European times,” she answered.
“What’s that?”
“There are different mouths.”
“Mouths? What’s that got to do with it?” I asked.
“Different communities have different mouths for different foraging. In pre-European times, bison would roam across grasslands and eat the grass. They have U-shaped mouths and aren’t able to pick up fine parts of plants like flowers or leaves. After the bison, the antelope would follow and they would eat the forbs and brush, or plants with leaves and flowers. This would help keep plants in control that might take over from the grass. Everything was kept in balance. Goats have V-shaped mouths and therefore can pick off leaves in fine detail like they are doing here.”
“Are they just going to eat the leafy spurge and other plants like Canada thistle or poison hemlock? What about wildflowers?” My passion is wildflowers. Would there be any left, I wondered?
Just as I asked that question, I watched the goats forage in a tight herd configuration. Under their little hoofed feet the grasses were pressed down, forbs stems stripped of leaves, some brush nibbled. I noticed that, at least on the first pass, lupine, yarrow, and sunflowers were left untouched.
“Goats can graze plants that are toxic to other animals because they have a large liver that helps process toxins. And, they do not pass viable seeds through their systems,” Lora answered, while continuing to watch the herd, dogs, and her two-year-old son, Jack. Jack asked his own questions, which usually began with “What’s this?” The goats ignored us as they chowed down with great speed, stripping the leafy spurge of leaves. They didn’t appear to mind being in close contact with each other, as opposed to cattle who wander apart most of the time.
“Today there is a huge increase in noxious weeds because of many years with no control," Lora continued. "Many communities avoid spraying and there are no animals to feed on weeds, so they have taken over. Goats are one management tool in the whole toolbox of options. Sometimes an area is too large for goats and spraying is necessary. But goats are better suited than cattle to rugged and steep terrain.”
“How is goat management better than spraying herbicides?” I asked, brushing on a hot topic in today's news.
“While the plants are flowering, like now, the root system is the weakest. When the leaves are stripped, the plant can’t photosynthesize over the summer. Also the plants don’t develop a resistance to grazing they way they might to an herbicide. Grazing needs to occur for three or more years in a row in order for the root to completely die away. Hillsides where the leafy spurge is at 80%, like parts of the Drinking Horse Trail system, will appear bare for those few years until the leafy spurge is sufficiently weakened to allow the rest of the plant community to compete and spread again. Goat-grazing management is the right tool for this job,” Lora replied, while Jack wandered off to smell the lupine.
“Another benefit to having goats here is that they pulverize their poop into the ground, thereby fertilizing the soil,” she added.
“How did you get started with all this goat business?”
“I took a class with Cliff Montagne at MSU titled ‘Herd Dynamic,'” Lora replied. "It made a lot of sense to me and I felt I had found my niche. For a couple years I worked as a herder in Montana and Wyoming. Then I worked for another company and now I’m with Prescriptive Livestock Services. I also did some work a couple summers in Mongolia where they herd on foot or with horses. I couldn’t do this job here without the dogs.”
“Where’s Alex from? I heard you speaking some Spanish with him.”
“Alex is from Peru. He’s been with us for about three years. The two border collies are his as well as the Great Pyrenees guard dog. I couldn’t do this without him or the dogs. We have the trail closed because of concerns about hikers coming with dogs. The Pyrenees’ first job is to protect the goats.”
“What’s the essence for you of goat herding/management?”
Lora laughed out loud. “I’m happy outdoors with goats and dogs. It cheers me up even on bad days. I manage this herd of goats because of quality of life issues—a love of being outdoors and embracing the environment of Montana. I love being able to have my son with me, out appreciating what we have. I was raised on a farm and wanted to be able to raise my kids with as much outdoor natural time as possible.”
“That sounds like the perfect job.”
“I also love the social component this land management approach has. People ask questions, learn about the plant community, and enjoy seeing the animals work. It brings a community connection to our landscapes and management issues.”
As we amble down the trail with goats munching weeds all around, it goes without saying that a third componenet is the work itself. When the goats have done their work, the hillside will be free of invasive pants and even more beautiful—and that’s something be proud of.
For more information, visit the U.S. Fish & Wildlife Service's page on goat-grazing, and watch a video of the recent Drinking Horse goat-grazing here.
