Remember the R’s: Rest

Aim to rest pastures much longer than you graze them for optimum production, more resilience, and healthy soils

By Lynn Betts

“Think of your grasslands as your children,” says Tanse Herrmann. “Both are ever changing and developing, and both of them need rest.”

“We make our young children take naps to stay healthy, and we need to give grasslands rest after grazing to keep them healthy, too,” the state grazinglands soil health specialist for the USDA Natural Resources Conservation Service in South Dakota says. “But their rest period is longer—a minimal 45 days, often 365 days or more. The goal is to allow all plants in the pasture to regrow and fully complete their growth cycle.”

Long rest to recover

Gene Ausland saw the destruction caused by overgrazing first hand more than 20 years ago, and learned how long that land in the Coteau Hills had to be rested to recover. “We live in eastern South Dakota in Day County where we get more rain than they do out West, but our ground is in the edge of the Hills, so we’ve got some very rough, marginal ground,” he says.

“About 20 years ago, we had grass in a dry year and rented the pasture to a guy who had run out of grass. We had a deal that he would put his cattle there for a week, two at most—but he kept his cows on it for a month,” Ausland recalls. “They ate her to the ground, and ruined the root system. It took five years of rest, no grazing, absolutely no grazing to bring her back.”

Ausland hasn’t let that happen again. “We used to graze in 120-acre pastures, but we dropped that down to 40- and 20-acre paddocks to control the grazing more,” Ausland says. “I’m out in a pasture every day checking grasses to see when we should move—if it’s going down too fast or if we should stay for a few more days to get the right amount of grass. We try to leave anywhere from four to six inches of grass standing in the pasture every year. We graze a pasture once a year and then it rests for another year.”

“With the pastures resting all the time, in our last drought here, we have grass that is two to three feet tall where other pastures are six to eight inches tall around us. It’s a lot of hard work and a lot of dedication, but in the long run it pays off big time because you’ll have grass when you need it.”

Think about elite athletes

“To me, a good way to think about your grasslands is to compare the rest they need to elite athletes,” Herrmann says. “A marathon runner isn’t going to run a race two days in a row. He or she needs much more time to rest and recover. The same is true for race horses. Their owners wouldn’t even think about running them two days in a row without more rest. When we are trying to develop the most resilient grasslands we can, we need to think about the need for rest the same way.”

Another analogy is with the boxer that keeps getting knocked down, Herrmann says. “If that boxer gets knocked down repeatedly, and gets up in an injured or weaker state each time, there comes a point he doesn’t get up at all. Our grasses react the same way—if they are grazed into the ground and then the new growth is nipped off again and again without rest, there comes a point the roots stop growing and the plant doesn’t survive, let alone thrive.”

Rest requirements vary

The most common rest period is a year—once-through grazing followed by rest until the next year. “Some systems are twice-through,” Herrmann says, “where livestock graze the top one-third to one-half of forage the first time through. Then comes the longer rest. In a twice-through management system, the second grazing event should be carefully monitored to be sure there’s enough plant material left after grazing, to maintain enough leaf for photosynthesis to feed the soil through root exudates, and to ensure roots and leaves continue to grow.”

In drought years like 2021, Herrmann says, you’ll want to delay turn in dates in 2022 in many cases. “Even if next year has normal rainfall, we wouldn’t expect we will get full production in 2022, unless those pastures are very well managed,” he says. Those well managed pastures likely have healthy soils that infiltrate and hold moisture.

They’re the opposite of continually grazed pastures. “In pastures grazed all season long, that were hurting before the drought, it could take three to four years to get back to full production. The bottom line is it takes even more rest to recover from drought years.”

Editor’s note: Third in a 6-part series recommending ranchers break down grazing management principles to memorable “R” actions that lead to resilient grazinglands on South Dakota farms and ranches.