Grazing is a powerful tool for improving the health of plants and the soil supporting them when it’s managed correctly.
“Well-managed grazing can maintain or even enhance soil health, while unmanaged or poorly managed grazing can degrade soil health,” said Steve Nelle, a range and wildlife consultant who worked with the USDA-Natural Resources Conservation Service (NRCS) for 35 years before entering the private sector. “The range of effects is great.”
Beneficial, well-managed grazing goes by many names including planned grazing, intensive rotational grazing and adaptive multi-paddock grazing. Regardless of the name, beneficial grazing systems incorporate several principle practices.
Dr. Richard Teague, a range ecologist who serves as Professor and Associate Resident Director of Texas AgriLife-Research, identifies these practices as:
- Adjusting stock levels according to available forage and leaving enough to maintain essential ecosystem functions;
- Using short grazing periods of one to three days;
- Allowing full recovery of grazed pastures before grazing again;
- Constantly monitoring the forage and adapting the grazing strategies as conditions change.
“There is no one-size-fits-all prescription for grazing because every ranch is different and every family has different goals,” Teague said. “The principles remain the same, but the application differs based on the location.”
“Plants in low rainfall areas or dry times need a longer recovery period than plants in higher rainfall areas or wet times,” said Teague, who uses the name adaptive, multi-paddock grazing to identify these grazing practices.
Adaptive, multi-paddock grazing mimics the “graze, rest and recover” rhythm naturally developed on the American plains. Rangeland plants evolved with periodic grazing pressure from vast herds of nomadic animals such as bison. Historically, the herds came in large numbers, grazed intensively for a short time and moved on, allowing the plants to rest and recover before the herds returned and consumed the fresh growth.
As the plains were settled, livestock replaced bison and fences stopped free-ranging movement. Livestock, like people, have food preferences. When grazing animals are confined, they will continue to seek out their preferred forages until those plants disappear. Then, they will seek out the next desirable plants, eating them out of existence and creating a less diverse buffet of less desirable plants and increasing bare ground. This results in rainfall runoff, which erodes soil and reduces soil and forage production.
“There is direct relationship between what happens on the land and what happens in the soil, so less diverse vegetation translates into less diverse microbial life in the soil,” said Nathan Haile, conservation agronomist with USDA-NRCS. “When we erected fences and held livestock, it disrupted the biochemical communication between the animals, the plants and the soil microbes.”
Grazing for Healthy Soil
Fortunately, Mother Nature is resilient and responds to grazing management that mimics the “graze, rest and recover” rhythms of the nomadic grazing herds.
Livestock, generally cattle, assume the role of native herd animals, with managers allowing them to graze intensively for a short period of time based on the amount of forage that’s available.
“When an animal rips into a plant, the plant releases chemicals that signal soil microbes that it’s been damaged and needs to be repaired,” Haile said. “That signal prompts the soil microbes to kick out acids that free up the essential nutrients the plant needs to repair and regrow.”
For the system to function, the plant must be given time to recover and begin photosynthesizing again before it’s grazed. Photosynthesis captures the sun’s energy and produces the sugars that nourish the plant, the animals and the soil microbes.
“Many times, people focus on the grazing period, but from my perspective the recovery period is even more essential,” said Haile, noting recovered and reinvigorated grasses send their roots deeper into the soil creating more surface area for chemical interaction, deepening channels for water infiltration while increasing resistance to erosion and tolerance to drought.
In addition to kicking off the biochemical reactions by grazing the plants, the cattle mechanically alter the soil. Livestock’s hooves disturb capped soil. They trample standing dead vegetation, which unlocks trapped nutrients, creates protective surface litter and adds organic matter to the soil. Organic matter not only provides nutrients but improves the soil structure by creating pockets that hold water and air.
“They [livestock] return about 25 percent of what they eat back into the soil as manure and urine, which are rich in nutrients and organic compounds which help feed the soil organisms,” said Nelle, noting that healthy soil supports large populations of dung beetles that bury the manure and speed up the process.
As the amount of grass cover, litter cover and organic matter increases, roots lengthen and spread and soil structure improves as does water infiltration. Obtaining and retaining moisture is a key to improving soil health.
“All chemical reactions occur in the presence of water,” Haile said. “Without moisture, the energy-rich carbon can’t be released, and the soil microbes go dormant. None of the necessary chemical reactions that support plants can take place.”
Understanding the role that water plays at the biochemical and cellular levels also explains the role that annual rainfall plays on the rate of positive changes across the landscape.
“Regardless of where you are in the world, adaptive multi-paddock grazing that is implemented properly begins to yield positive results that begin to accrue quickly as plants are reinvigorated,” said Teague, who conducts research and works with landowners throughout North and South America. “What varies—and it’s dependent on the amount of rainfall—is how quickly the land responds on a large scale. Higher rainfall means carbon infiltrates more readily, which speeds up the ‘healing process.’”
Significant changes that take five years in Mississippi, might take 10 years in the Texas Panhandle and 25 years in the deserts of New Mexico, he said.
Regardless of the time period, as long as managers continue to measure and monitor forage availability and adapt to changing conditions, positive changes beget positive changes.
“Vigorous, green growing plants capture the sun’s energy and send that energy into the soil where it’s used by soil microbes including bacteria, fungi, protozoa and earthworms,” Haile said. “The microbes, in turn, make soil nutrients more readily available to the plants further improving their health. They support each other—and once plants improve, soil health and plant health move forward together.”
When that happens, the results are obvious and far-reaching. Teague recalled a large-scale project in Patagonia, a dry region in Argentina, where many ranchers were trained to properly implement adaptive, multi-paddock grazing. Within a year of their collective efforts, the group had to go to the Argentinian government and the Nature Conservancy to get special permission to contend with the large number of wildlife and birds that had been attracted to their grazing lands because of their robustness.
He’s seen and measured similar results obtained by landowners across Texas, in the southeastern and southwestern United States, Canada and northern Mexico.
“Grazing matters to plants and soil—and to every living thing that depends on them for life,” Haile said.
Milestones of Change
For thousands of years, Texas rangelands were populated by huge, nomadic herds of native grazers such as bison and pronghorn. Typically, the herds would move into a fresh area, graze it down and move onto the next “ungrazed” section of range.
The herds wouldn’t return until the weather and lack of grazing in other areas brought them back. In between the herds’ visits, the plants would recover and grow anew.
Although the Spanish explorers arrived in the late 1600s, this natural system remained basically intact and undisturbed until the 1830s and 1840s as the pace of settlement increased. Since that time, Texas has changed, and along with it, so have its rangelands.
Some major milestones that have influenced and, in many cases, accelerated the changes include:
Post-Civil War Era (1865–1880): The years immediately after the Civil War were a time of cataclysmic change. Bison were slaughtered for commercial purposes and as a means of wresting control of the plains from the Native American tribes such as the Comanche and Apache. The disappearance of the bison coincided with the rise of the cattle trailing. Longhorns and other cattle breeds replaced native wildlife as the primary grazers as legendary cattlemen with names like Swenson, Slaughter, King and Reynolds established their empires. Barbed wire, invented in 1867 by Lucien B. Smith and improved and patented in 1874 by Joseph B. Glidden, signaled the end of the open range.
Turn of the 20th Century (1900–1910): At the beginning of the 20th Century, publications such as the Texas Farmer Stockman were filled with ads offering vast tracts of Texas for less than $10 an acre. Texas’ wide-open, wild spaces filled and were settled rapidly.
The Great Depression and the Dust Bowl (1930–1939): Economic and ecological hardship in the form of an extended drought did not spare Texas. Known for its weather extremes, Texas is home to periodic droughts, including extended ones such as that of the Dust Bowl years and the “Drought of Record” in the 1950s that lasted seven years and put many agricultural producers out of business. Droughts continue today, including the drought that ravaged Texas from 2010–2015; it peaked in 2011, the state’s driest year on record.
The Great Conversions (1945–present):
From native range to introduced grasses: Soon after the close of World War II, introduced grasses, such as coastal Bermuda, bahia and buffelgrass, prized for their forage-per-acre productivity, supplanted native range. At the time, inputs were inexpensive, and the goal was to produce the most pounds of animal protein or fiber per acre. The ecological impacts of introducing a grass monoculture were unanticipated.
From grass to brush: Continuous grazing on relatively small, fenced pastures combined with the suppression of wildfires created conditions that helped brush species, once confined to draws and riparian areas on the plains, establish across the range. (Some parts of Texas have always been wooded.)
From livestock to wildlife: Beginning in the late 1800s, Texans purchased land intent on ranching or farming. Beginning in the mid-1980s, many producers began to diversify their income by developing hunting and wildlife enterprises on their properties. In 1995, Texas voters passed Proposition 11, which created a wildlife property tax valuation, allowing landowners to maintain a production tax base while managing for wildlife and its habitat.
From a rural state to an urban state: In 1970, Texas had about 11.2 million people. By the year 2000, the population had grown to 20.4 million. Today, it is estimated that there are 29.1 million Texans—and the number is growing. More than 86 percent of those Texans live in urban areas. The unprecedented population growth is spurring urban and suburban sprawl; between 1997 and 2017, Texas lost two million acres of farms, ranches and forest lands. The Lone Star State is losing open space land faster than any other state in the nation.
The Great Needs (2019–future):
Agriculture and wildlife: At points in time, it appears that the livestock industry and wildlife enthusiasts have been at odds. With open space land, which provides both agricultural productivity and wildlife habitat, disappearing at an alarming rate, it is important that the two groups galvanize for the common good of working lands. Once working lands are converted to suburbs and strip centers, it is gone forever.
Ecosystem services: As the amount of open space land disappears, so does the “engine” for essential ecosystem processes such as the water cycle, oxygen production and carbon sequestration that are necessary for human existence. If the remaining land is degraded, its ecological productivity is limited at a time when rising population demands more clean water, air and other life essentials. Good land management produces ecological benefits as surely as it provides raw commodities or other crops. The challenge is creating a market for these ecosystem services that provides an additional income stream for landowners further diversifying their operations and providing incentives for them to optimize their management for ecological products.
Adapted from remarks by Dr. James Cathey,
Associate Director, Texas A&M Natural
Getting Started with Adaptive, Multi-paddock Grazing
- Get educated. Go to one of the schools that teaches the basic principles of adaptive, multi-paddock grazing. Good ones include: The Soil Health Academy, Ranching for Profit and Holistic Management International.
- Talk to successful practitioners, especially those in your region. Training is essential. Real life experience from those who have succeeded in your area will help new practitioners avoid costly financial and ecological mistakes. Local people with local experience can help newcomers gauge adequate periods of grazing, rest and recovery for their environment. For instance, the recovery period may be 30–40 days in East Texas, twice that in the Panhandle and even longer in the arid Trans Pecos.
- Invest in water. In order for herd consolidation to work, producers must provide adequate water in each paddock.
- Consolidate your herd. Most ranches are divided into eight paddocks with one herd in each. Don’t spend a lot of money changing fences; instead, combine your small herds into a single large herd. Begin rotating them based on forage availability.
- Monitor and adapt. Monitor the condition of the land, the plants and the livestock. Adapt your grazing efforts to changing conditions.
- Think differently. Identify your goals and consider how to achieve them by working with nature, even if the approach may seem unorthodox.
The Gill family of San Antonio owned the Circle Ranch in the Trans Pecos for several decades. The area only gets rain in July. The family did not stock until after the summer rains came and they assessed how much vegetation they would have. Then, they arranged with a lessee to rotate a herd through the ranch one time to graze standing vegetation, break the soil cap and increase organic matter, all of which resulted in improved wildlife habitat, which was their primary goal.
The solution was completely appropriate for the environment. By working through a lease agreement, the family minimized the economic risk that comes with owning livestock and gave them additional flexibility to change with the weather. They only embarked on a grazing regime if they had vegetation to support it. (The Gill family recently sold this property and began ranching in Idaho.)
Adapted from remarks by Dr. Richard Teague, Professor and Associate Director Texas A&M AgriLife Research
By Lorie A. Woodward for Land.com