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NATURAL RESOURCE SCIENCE AND MANAGEMENT IN THE WEST

Conservation grazing: Ranchers lead the way

Jan 6, 2014

On the Howell Ranch and adjacent properties in western Colorado, cattle are used to create prime elk hunting opportunities. Managers carefully consider elk movements when they design the annual grazing plan for the ranch. conservation-2In May and June they keep cattle away from elk calving grounds. Then the ranch hands concentrate cattle in favorite hunting spots in the first half of the growing season, and move them to other areas later in the summer, letting forage recover. When fall rolls around, those elk hunt areas are thick with new grass full of protein and energy.

“The elk appreciate that and have learned that. During the fall, in terms of grazing patterns, they tend to concentrate on areas grazed early,” said Jim Howell, CEO of Grasslands LLC, and heir of the Howell Ranch. “The numbers are higher than ten years ago before we implemented it. There are almost too many elk.”

The increased elk numbers are just one example of wildlife benefitting from new and improved management at the Howell Ranch. In an uncommon example of wide-scale ecosystem engineering, Howell and his team have made gradual, large-scale changes to how they move cattle through this and other ranches, and by their count they have successfully improved forage, biodiversity, and notably, livestock productivity. Scientists, however, who have studied “rotational grazing”—one term for the kind of practice Howell has implemented—have been unable to measure the benefits ranchers like Howell claim.

The Howell Ranch on Colorado’s arid western slope spans deep, rocky canyons. When the ranch was managed using traditional grazing practices, cows roamed large pastures for extended periods throughout the year. They tended to concentrate along streams, munching fresh sprouts of plants trying to recover from recent grazing. Meanwhile, they never reached the bunch grasses high on the steep, forested slopes.

Under new practices implemented by Howell, ranch managers fence cross sections of the canyons about 600-800 yards wide with portable electric fences running from ridgeline to ridgeline. This creates a level of stock density that motivates the cattle to climb the slopes in a way they never did under low density, continuous grazing. As Howell describes it, on the first day the cattle graze along the creek bottom. Then they start climbing the slopes. They readily move up into the forest and by day two of a grazing period many cattle have reached the ridgelines. After three to five days, the managers move the cattle to the next fenced pasture.

conservation-1Cattle also replace fire as a management technique on the Howell Ranch. Whereas some managers use fire to clear out decaying vegetation and trigger a flush of recovery, the Howell Ranch achieves that with cattle. Fire is too dangerous in western Colorado, and takes a lot of work to carefully burn even a small area. Instead, focused intensive grazing creates localized patches of regrowth attractive to wildlife and develops a mosaic of vegetation ages across the ranch.

Howell has ranched, consulted, and traveled in Argentina, Australia, Zimbabwe, South Africa, and New Zealand. In the mid 90s he and his wife, Daniela, managed the 34,000-acre High Lonesome Ranch near Lordsburg, New Mexico, where they deepened their management experience. When Howell and his wife moved back to their family ranch, they started to adjust grazing patterns. The switch from traditional to conservation grazing didn’t happen all at once, but was gradually implemented season-by-season and year-by-year.

“The most important step is to get the mental shift to observer of ecology and animal behavior,” said Howell. “You have to have managers on the ground with a research bent. They think in the abstract. They are not just strict cowboys.”

That intellectual shift was the hard part, according to Howell. The infrastructure costs amounted only to grazing planning charts and a few reels of portable electric fence. Patience, trial and error, and gentle treatment helped the cows break old habits and learn new grazing patterns.

Howell’s work in western Colorado is just one example of an outfit adopting altered grazing management and seeing benefits in grass production and habitat. Rotational grazing, as it is sometimes called, has been applied in the United States for about 45 years, and has become more sophisticated and widespread as decades pass.

The November 1969 issue of the American Society of Range Management’s journal introduced the concept of intensive, short-duration grazing to North America. Range managers in Zimbabwe (then Rhodesia) were exploring the method. The idea was to concentrate livestock into small pastures and move them frequently. The paper’s author, Sid Goodloe, wrote, “I saw ranches (in Africa) where existing fences had been stripped of one or two wires and those wires strung from tree to tree to divide pastures until the increased carrying capacity brought in enough money to build permanent fences.”

Short-duration grazing, Goodloe wrote, “breaks the parasite cycle, puts the standing dry grass (top hamper) down to litter, eliminates trails to and from water and chips the soil surface for better seed germination.” Most importantly, ranchers applying the practice claimed they were able to reverse rangeland degradation even as they increased livestock numbers. Livestock would make better use of the available forage, according to proponents, and rangelands had time to grow back after each period of intense grazing. Ranchers could then raise more livestock on the same piece of land. Ranchers in Zimbabwe were enthusiastic that these new methods might help reverse deterioration of rangelands caused by long-duration or continuous livestock grazing. “The ranchers argued that results were plainly visible and that they couldn’t wait for years of research,” Goodloe wrote.

After publication of this paper, U.S. ranchers began to apply the practice with equal enthusiasm and results. It has gone by different names—short-duration grazing, holistic rangeland management, rotational grazing, conservation grazing. Many ranchers who have adopted rotational grazing, like Howell, swear by it. They say it has improved grass production and habitat diversity, repaired damaged streams, and reversed rangeland degradation. Many can share anecdotes of wildlife—from sage grouse to elk and from beavers to songbirds—returning to areas where they’d been absent for decades. And ranchers also claim they are able to increase stocking rates with rotational grazing because the animals have better access to more nutritional forage.

When Wayne Fahsholz started running the nearly-475,000-acre Padlock Ranch in the early 2000s he implemented what he calls a controlled grazing system. Electric fences keep cattle bunched in smaller pastures, and the animals are moved frequently—every few days to every few weeks. Fahsholz picked up these practices from working on other ranches, and from attending the Ranching for Profit School, a program that teaches ecology alongside finance and grazing management.

“We have some massive spreadsheets,” Fahsholz said. “Every two weeks our cowboys turn in an inventory of cows, the amount of supplement the cows used, what pastures they have used, and how many cows were in that pasture.” That information is entered into a database and used to ensure that the same pastures don’t get grazed too often, too long, or at the same time of year for consecutive years. In the winter the managers look at pasture conditions and correlate that to how many cattle were in each pasture at a given time of year, and for how long. They set up guidelines for the coming grazing season, but rely, too, on cowboys looking at pasture condition and deciding when the cattle need to move on. “It’s not an exact science,” Fahsholz said.

But while ranchers extol the benefits of the practice, scientific studies have measured none of the proclaimed improvements to rangelands and livestock productivity. Despite claims of improved rangelands from ranchers, scientists who began to study rotational soon after Goodloe’s paper was published have arrived at startling results. Controlled studies of rotational grazing have been unable to detect the benefits ranchers describe. Numerous studies over the decades measured reduced infiltration of precipitation into soils, no change in forage production, declined ecological condition of ranges, and lower livestock productivity.

These studies have teased apart the separate influences of grazing duration and stocking rates. One review, published in 2000 and authored by Jerry Holcheck and four others, scrutinized efforts by researchers at 13 locations in North America to validate short-term rotational grazing effects on plant succession, mineral cycling, water filtration into soil, and other purported benefits. The review stated:

  • Hoof action from having a large number of animals on a small area for short time periods reduced rather than increased infiltration
  • Short-duration grazing increased erosion compared to continuous or season-long grazing
  • There is little difference in forage production between short-duration and continuous grazing systems if stocking rates are the same
  • Short-duration grazing [was] similar to continuous grazing in effects on plant succession and range condition if stocking rates were the same
  • Several studies showed that livestock didn’t gain weight as fast under short-duration rotational grazing as compared to continuous grazing, while other studies showed no difference and one study showed livestock gained extra weight with rotational grazing

A major study by W.A. Manley and five coauthors, cited in the above review, analyzed both grazing duration and stocking rates, and measured the effect of each on surface and underground biomass, plant species composition, and groundcover from 1982 to 1994 in southeast Wyoming. The researchers created a matrix of study plots and, for the 12 years of the study, assigned each plot a grazing strategy (continuous, seasonally deferred, or short-duration rotational grazing) and a stocking rate (from light at 0.16 steers per hectare, to heavy, 0.56 steers per hectare).

The researchers found that under heavier stocking rates—that is, with more livestock per acre—native grasses decreased and forbs increased over the years of the study, regardless of grazing strategy. They also found that steers gained less weight per hectare of land when they were heavily stocked compared to plots with fewer steers per hectare.

Rather than informing management practices, such findings have ignited controversy between advocates of rotational grazing (and the ranchers who believe it works) and ecologists who argue that increasing stocking rates come with no ecological benefit. Holcheck, author of the above review, wrote in his conclusions, “History shows that it’s human nature to believe a good story rather than pursue the truth,” adding his claim that only reducing stocking rates could help rangelands recover from decades of abuse. He even attributed financial losses experienced by ranchers in the 90s and growing conflict between ranchers and environmentalists to high-risk management strategies involving high stocking rates.

Justin Derner and his colleagues are among the ecologists starting to tease apart these discrepancies and understand from a scientific perspective how grazing can be used as a tool to improve the ecological health of rangelands. In a 2011 paper in Rangeland Ecology and Management titled “Origin, Persistence, and Resolution of the Rotational Grazing Debate: Integrating Human Dimensions Into Rangeland Research,” Derner and five co-authors listed variables rangeland scientists may not be accustomed to accounting for in their experiments: ranch managers’ goal setting, experience, and decision making. They wrote

The scientific evidence refuting the ecological benefits of rotational grazing is robust, but also narrowly focused, because it derives from experiments that intentionally excluded these human variables. (Emphasis original.)

The authors argue that a rift exists between the piercing scrutiny of highly controlled scientific study and the broader reality of natural resource managers continually adjusting their prescriptions. The authors call for recognition of the limits of scientific knowledge as applied to management of such complex natural resource subjects as rangeland ecosystems, and propose developing a new model by which research of such ecosystems can account for human dimensions when measuring management practices.

In another paper (“Livestock as Ecosystem Engineers for Grassland Bird Habitat in the Western Great Plains of North America,” Rangeland Ecology and Management, 2009), Derner and three different co-authors describe, much as in the accompanying feature article, methods for managing grazing to promote diverse rangeland vegetation. Moving beyond electric fences to control livestock movement, the authors recommend placing supplemental feed and water and herding as methods to get cattle to graze some areas more heavily than others, thus creating a mosaic of vegetation of different ages and heights. Such approaches, they say, can help rangeland managers achieve both conservation and production and offer an alternative to ending public lands grazing for conservation purposes.

Meanwhile, no one is measuring “biodiversity” on rangelands to test whether new practices are reversing loss of species. Ranchers and the BLM measure grass production, usually by measuring grass heights and other metrics. Wildlife agencies and some conservationists monitor rangelands for target species (such as sage grouse) or count plant species and abundance.

On the Howell Ranch regular monitoring transects prove that plant diversity and ground cover have improved with the new practices. Active monitoring of wildlife biodiversity isn’t happening, but Howell said, “Whenever you are enhancing plant diversity, that opens niches for all kinds of wildlife from insects to birds to mammals.” Anecdotally, such as with the elk hunting successes and sage grouse monitoring projects on other Grasslands LLC ranches in Montana, biodiversity has increased with conservation grazing. Species once rare or absent are returning.

“In any given year, we leave up to half of the ranch ungrazed, and these pastures are mixed throughout the ranch, so we have a mosaic of ungrazed and grazed patches,” Howell said. “And, all of the grazed patches are in different stages of recovery, with different vegetation structures. We effectively create a diverse landscape spread throughout the ranch, conducive to attract a diversity of wildlife.”

Since he came to the Padlock, Wayne Fahsholz has been able to increase stocking rates, give less supplemental feed, and work with a smaller crew of cowboys. In addition, he said, the U.S. Fish and Wildlife Service tells him the ranch has created some ideal sage grouse habitat. “The overall range is better,” Fahsholz said, “but you really see it in the riparian areas. They aren’t all tromped out like they were.” And the Padlock Ranch has been sweeping up conservation awards. The ranch won the 2013 Leopold Conservation Award and the 2012-13 Montana Environmental Stewardship Award and was nominated for the National Cattlemen’s Beef Association’s Environmental Stewardship Award.

Chris Pague, a senior conservation ecologist for The Nature Conservancy based in Colorado, sees a trend to more and more ranchers applying new science to improve rangeland management in ways that both boost vegetation productivity and benefit many wildlife species. The next step is to jump from measuring not just rangeland quality – that is how nutritious and productive is the vegetation – but to measuring the value of those rangelands for wildlife and biodiversity.

Achieving such measurements will require a new kind of thinking and widespread coordination that hasn’t happened to date for biodiversity on private and public rangelands in the West.

By Emilene Ostlind