Organic Broadcaster

Research shows farmers use mob grazing for variety of benefits

By Anders Gurda, University of Wisconsin-Madison

For those of us interested in grass-based agriculture, mob grazing is likely not a new concept. We’ve heard the mob-grazing gurus talk at conferences, read the articles, and listened to fellow farmers or agricultural advocates rave or rant about it. Although it has been the subject of much discussion, there still seems to be a lack of consensus about how mob grazing should or should not be implemented. As is true for any production strategy, there is no one, right way. Learning about the many right ways that mob grazing can work for graziers has been the focus of my research for the past few years.

What is Mob Grazing?
Mob grazing finds its inspiration in the behaviors of wild, rangeland herbivores such as bison and elk in the American West. Those lumbering ungulates roamed in miles-long herds, grazing, trampling, and fertilizing the plains as they moved. The heavily disturbed path they left would recover and regrow, likely not to be grazed again for many months or years. It was exactly this pattern of disturbance and rest, along with periodic fires, that created some of the richest soils in the world. If the Midwest owes its considerable agricultural inheritance—a disappearing Loess-rich nest egg—to this recurring interplay between forage and forager, then why wouldn’t we want to mimic this system?

“That soil didn’t just happen,” says Cheyenne Christianson, a Wisconsin dairy farmer. “Something made that happen.” It’s mob grazing that Christianson thinks will keep this fertility-giving process going into the future as we domesticate this practice and scale it down from limitless prairie to fenced pastures. While bison were kept in a tight, constantly migrating group by predators and food scarcity, in mob grazing, the electric fence replaces the snap and snarl of a wolf, and the farmer moves the animals when fresh forage is needed.

A grazier can be seen as the facilitator of an evolutionarily honed and ecologically defined relationship between herbivores and grassland. How that interplay is choreographed depends on soil type, climate, breed, and vegetation, among many other factors. No two herd managers have identical land, nor will they use identical management strategies. Just as “weeding” can mean anything from using your thumb and forefinger to pluck an offending lambsquarter from a coddled carrot row to pulling a field cultivator through a sprawling corn field, “mob grazing” can refer to high-density grazing at a variety of scales and intensities and with any number of goals in mind.

Research Focus
Farmers have been creatively implementing mob grazing for years as a practice synonymous with or closely related to ultrahigh stocking density and holistic management. Not surprisingly, it has taken researchers a while to catch up.

In 2011, while working on my graduate degree in Agroecology at the University of Wisconsin-Madison, I embarked on a three-year journey through the pastures of Wisconsin, researching mob grazing and exploring an emerging practice still taking shape on the landscape.

The main thrust of my research focused on mob grazing as a control strategy for Canada thistle. However, I also conducted a series of interviews with mob graziers throughout the Midwest to see the method in action.

The field research compared three treatments and their impact on Canada thistle populations and forage production over three seasons: a one-time fall herbicide application followed by rotational grazing, mob grazing, and a rotationally grazed control. Simply put, we found that mob grazing may be an effective control strategy if used in diverse, productive pastures, but may increase thistle density in less productive swards. Although a moot point for organic farmers, the herbicide application, while effective, also killed all desirable broadleaf forages including nitrogen-fixing, protein-rich legumes, and reduced the total amount of available forage.

If grazed at vegetative-to-flower-bud stage, Canada thistle has good forage quality and can be part of a well-balanced (protein:fiber) ruminant diet. If a thistle infestation is severe; however, utilization will decrease, and control may be necessary. If using non-chemical control, and if portable fencing is available, we recommend strategically using a stocking density of at least 400,000 lbs. of live weight (our mob density) per acre applied across the entire infestation. Infested paddocks should be grazed when the thistle has reached flower-bud stage, or just before if forages are getting overly mature, to maximize impact and utilization. Animals should be left in the paddock until thistle stems are severely damaged, eaten, or trampled, after which pastures should be rested for an extended period (60-90 days) to allow for desirable forage to regrow and compete with reemerging thistle shoots. One grazing event in June (flower-bud stage), and another in September when thistles may be flowering again may enhance potential control. This strategy should be used for at least two years, and more if possible, until acceptable control is reached.

Farmers’ Experiences
As mob grazing has primarily been a farmer-generated practice, we went right to the source, learning from producers not only their reasons for using or not using mob grazing, but also how they actually implement the practice. I was lucky enough to take a week-long road trip in the summer of 2013 through Iowa, Minnesota, and Wisconsin—an experience that brought the practice to life. Armed with a video camera and lots of questions, I spent time with 10 very gracious farmers who use mob grazing (and don’t mind cameras in their faces) and was able to see, firsthand, what mob grazing looks like on the landscape, why it should or shouldn’t be used, and how best to implement the practice.

At every farm, I was struck by how mob grazing was adapted for that farm, and the reasons for those adaptations. While some farmers were really just “toying” with the practice, others had learned to be flexible, doing “what the environment, what the weather, and what Mother Nature tell you that you have to do,” as one farmer explained.

At the time of my visits, many of the grazing farms were destocked to average rotational densities. Using higher stocking densities in the spring and then slacking off as the summer heat came on was a common practice. I learned that mob grazing is a strategic tool that can be used for various amounts of time and to various degrees depending on the manager’s goals.

When asked to define mob grazing, most farmers laughed. When pushed, however, the farmers offered up that it generally includes higher stocking densities, more frequent herd moves, shorter grazing periods, grazing more mature forage, longer rest periods, and trampling much of the available forage to “feed” the soil.

Beef cattle graze on Dave Nortunen’s farm in northern Wisconsin. Mob grazing is similar to rotational grazing, but producers typically graze forage that is more mature with more animals per unit area, faster paddock moves, and a longer regrowth period after grazing events. Producers find benefits include weed control, even distribution of manure, pasture resilience, decreased animal selectivity and improved soil health.
Photo by Anders Gurda

Benefits
When asked to explain what benefits they’ve observed when using the practice, they couldn’t say enough. Many talked about soil health by relating observed increases in organic matter in mob-grazed pastures, better manure distribution, and the resilience of cooler, moister soils resulting from trampling.

Dave Nortunen, a beef grazier in northern Wisconsin, took a thermometer out to his pastures a couple summers ago and found that the soil under the mob-grazed thatch was 70 degrees while the temperature of bare ground was 94 degrees, a 24-degree difference. The cool season grasses that dominate temperate pastures are adapted to cooler, moister soils like those found under the trampled forage. Nortunen explained that as soon as he went to mob grazing, he hasn’t had to deal with the summer slump in production that results from increased temperatures.

Some of the graziers saw decreased grazing selectivity as a benefit. As Wayne Craig, a dairy producer in eastern Wisconsin, explained, “Instead of the behavior where they seek out specific grasses they like, there’s so many cattle around them that they realize, ‘if I don’t eat this, somebody else will.’” A large-scale beef grazier, Matt Ludlow, found that he was able to increase his stocking capacity by about 5% per year with mob grazing, due to decreased selectivity and increased forage production. “If you can do that without buying land, it’s a nice way to grow your business,” Ludlow added.

Animal performance might not be the first benefit that comes to mind when grazing mature forage, but many of the producers insisted that the increased fiber in the grass balances the protein-fiber ratio and ensures that cows aren’t too loose in the springtime and can utilize all of the energy in the forage. “It makes a perfect manure,” Craig said. These dairymen are also grateful for the excuse to see their animals multiple times a day, checking on watering systems, observing the animals grazing, and identifying problems preemptively. Craig finds that “seeing those cattle more often per day is a better thing.”

Disadvantages
Although there appear to be considerable benefits for farmers who have learned to adapt mob grazing to their operations, nothing comes without its drawbacks. Beyond the increase in labor and time, with moves happening more often, some farmers worried about animal performance.

“If you keep them [in the paddock] for a longer period of time and make them clean everything up, you’re going to hurt some individual animal performance,” Ludlow explained. But, he contends that the group will put on more total pounds in the end.

The dairy producers in the group emphasized the importance of careful management, encouraging those interested in mob grazing to graze earlier rather than later. “Be on that early cycle,” Christianson recommended. “You can register it daily in the bulk tank—see how fast that milk starts to plummet as that maturity cycle increases.”

Mob grazing may not be perfect for every type of livestock; it also may not fit every environment. Nortunen had some early challenges that resulted from mismanagement and not destocking in time.

“High density has some really good things,” he said. “You can really heal the land, and you can wreck the land probably twice as fast.” These growing pains are normal, other growers said, many relating that it may take a few years to see any of the impacts from adopting mob grazing.

“Get ready to screw up!” an Iowa beef producer warned when asked what advice he would give to other farmers interested in experimenting with mob grazing. Another manager gave a more nuanced view: “Take your time, and make adjustments as you go. Watch the condition of the animals.” These sentiments were echoed by all of the farmers. Start slowly, ask lots of questions, focus on trampling forage to “jumpstart” the system, use it in the spring, be flexible, and adapt.

Video Series
With the annual organic farming conference, this publication, and many other programs, MOSES facilitates an exchange that we all know to be the basis of effective agricultural education: that farmers learn best from each other. One of our goals as researchers is to facilitate these educational conversations. Realizing the videos I captured that summer might be valuable to other producers, we recently released a four-part series titled “In Their Own Words,” which covers mob-grazing definitions, benefits, risks, and implementation tips. (See bit.ly/MobGrazing.)

These farmers’ stories provide the most comprehensive picture of mob grazing to date, revealing it as an emerging practice with considerable potential but with drawbacks that can be overcome with slow and strategic implementation by producers.

A refrain that I heard throughout my travels was that mob grazing is best used as a tool, not an inflexible rule.

If mob grazing is a tool, then I’d like to think of it as a Leatherman—an infinitely useful multi-tool. From increased stocking capacity to soil health and resilience, mob grazing can be applied to the landscape in any number of ways for any number of reasons. Mob grazing elegantly applies ecological principles in a way that honors the system while simultaneously seeking to maximize production. But don’t take my word for it—I’m just a researcher—listen to your fellow farmers tell their own stories, in their own words.

Anders Gurda is an associate researcher in organic and sustainable cropping systems at University of Wisconsin-Madison. UW Extension, Hay & Forage Grower, Center for Integrated Systems, Ceres Trust, and SARE provided support for the videos.

From the July | August 2015 Issue

Comments are closed.