How can the most endangered ecosystem in the world be saved?

A jump in corn and soy prices is prompting the widespread conversion of native grasslands to crops.

On a sunny, sultry summer day, Joe Blastick, a land steward with The Nature Conservancy, scans the hilly pastures north of Clear Lake, South Dakota, and rattles off the names of plants he sees. Silver leaf scurf pea, purple prairie clover, green needle grass, and dozens of others blend into a cacophony of color and texture. Monarch and regal fritillary butterflies sample their nectar; meadowlarks and eastern kingbirds glide through the thick afternoon air.

 As impressive as the visible display is, the real action here is underground. Roots of grasses and other prairie perennials may descend 10 feet into the soil. Powered by the sun, these grasslands have for millennia pulled carbon out of the air and stashed it deep in the dirt. Grasslands store about a third of the world’s land-based carbon: They are one of nature’s original climate solutions. 

Ninety-two-year-old Herb Hamann, who owns these pastures, has carefully managed his 500-head cattle herd to make sure this 5,000-acre patch of prairie thrives. “I always loved grass,” Hamann says during my visit to his rustic farmhouse. Even through a severe drought this summer, his land stayed green and the cattle stayed fed. “In a tough year like this, I don’t have to worry,” Hamann says.

Hamann has put his land in a conservation easement designed to protect it forever. But he’s an increasingly rare specimen in this part of the world. Many other grasslands in the region, identified by conservationists like Blastick as a critical stronghold for imperiled plant, insect, and bird species, have in the past few decades given way to monocultures of two crops that the world can’t seem to get enough of: corn and soybeans.

A longer growing season, advanced seed varieties, and new farming technologies have all contributed to the Corn Belt’s incursion into the Great Plains. But the most important drivers, experts say, are economics and politics. A booming global market for commodity crops is being reinforced by two massive U.S. federal incentives: the ethanol mandate, which directs more than 100 million tons of corn annually to refineries that produce the gasoline additive, and crop insurance subsidies, which protect growers from financial losses.

 The relentless expansion of corn and soy farming poses a conundrum for the Biden administration. The president wants to cut U.S. agriculture’s net carbon emissions to zero—a tall order for a sector that currently puts more greenhouse gases in the air than 150 million cars and accounts for more than 10 percent of the country’s total emissions. Biden has also promised to conserve 30 percent of the nation’s land in a bid to protect biodiversity. Given that habitat for many threatened species is on private land, the government needs to not only create parks and preserves, but also engage farmers and ranchers in conservation.

Nowhere is that more true than the Plains. Every time a grassland is plowed or sprayed with herbicide and planted in crops, hundreds of deep-rooted perennial plants that can suck carbon into the soil and keep it there are wiped out. A 2019 study by Tyler Lark and fellow agricultural researchers at the University of Wisconsin estimated that tillage for cropland expansion put as much carbon dioxide into the air annually as 31 million cars. A 2018 study, led by The Nature Conservancy, found that in the U.S., conserving grasslands could prevent almost three times as much carbon emission as conserving forests.

The loss of the Amazon rainforest may get the headlines, but grasslands are even more imperiled, experts say. Roughly half of all temperate grasslands worldwide have been lost, compared to less than 20 percent of the Amazon. In 2019 alone, 2.6 million acres of North American grasslands were plowed under, according to a World Wildlife Fund report.

Grasslands, says Lark, “really are the most endangered ecosystem in the world.”

They took millennia to build

Fifteen thousand years ago, the northern Plains were buried under a massive ice sheet. When the ice retreated, a rich mix of plants moved into the region, which stretches from northern Iowa and western Minnesota across the Dakotas into Montana and Canada. Bison roamed the prairies in huge herds, chomping the tops of plants, fertilizing the soil with their manure and moving on. The plants grew back, all the while pulling in carbon and shuttling up to 80 percent of it to their roots, which pushed deep underground, building spectacularly rich soil.

When Europeans arrived, disaster struck in the form of the plow. Iowa and surrounding states, with a relatively mild climate, were transformed into the Corn Belt and have virtually no native prairie left. The northern Plains, with a harsher climate and thinner soils, escaped total conversion. While only 7 percent of northern grasslands are formally protected, more than two-thirds have remained intact, a sort of accidental nature preserve.

That reality is rapidly shifting, however. Today’s farmers can avoid the backbreaking sod busting of yesteryear by simply spraying herbicide and drilling in seeds. Those seeds have been customized for the Plains’ limited growing season and cold, dry climate.

When crop prices spiked, starting in the mid-2000s, U.S. farmers responded. Between 2008 and 2016, they converted more than 10 million acres of grasslands—a combined area nearly the size of West Virginia—to crop fields. The northern Plains were hit the hardest. Prices eventually receded, but earlier this year corn reached $7.70 a bushel and soybeans topped $16 a bushel, just a hair off their historic peaks. Corn acreage is up 2 percent in 2021, to 92.7 million acres. Soybean acreage jumped, on a percentage basis, more than twice that.

 Ground zero for conversion of grass to crops is the Prairie Potholes region, a Texas-sized expanse of rolling hills, flat land and shallow lakes extending from northern Iowa through the Dakotas into Canada. Fully half of North America’s ducks and other waterfowl are born in this region, and they need grasslands for their nests. The Potholes also are home to hundreds of plant and insect species, many of which are in decline. The Dakota skipper butterfly, for example, was recently listed as threatened under the Endangered Species Act, while the range of the regal fritillary butterfly, which once extended to Maine, has shrunk to prairie remnants mostly west of the Mississippi River.

Perhaps no animal illustrates the impact of grasslands’ decline more than birds. A 2019 study of bird decline singled out grassland birds as the most imperiled group in the country, with a more than 50 percent drop in overall population since 1970, and three in four species in decline. Birds that feed or nest only in grasslands include iconic species like the upland sandpiper, eastern meadowlark, grasshopper sparrow, and the bobolink.

A drive around eastern South Dakota makes clear the conservation challenge. Nearly all the land is privately owned, and it is home to essentially two things: cows and crops. While few people broadcast that they’re plowing up prairie, the evidence is abundant, if you know where to look.

Bruce Toay, a Ducks Unlimited conservation program manager based in Ipswich, South Dakota, drives me past 500 acres of corn planted on what had until this year been native prairie used to graze cows. Toay points out the fence, still in good condition. Brown-and-green chunks of busted-up sod are scattered around the field edges.

“It’s an ongoing battle. We’re constantly losing grasslands,” says Toay. “If we lose some every year, eventually we won’t have any left.”

Are cows the answer?

To Lyle Perman, the way to keep grass “right side up” and crops at bay is simple: more cows. Perman’s 10,000-acre ranch, folded into the hills east of the Missouri River, is about as remote as it gets. Like Hamann, Perman practices a brand of agriculture inspired by the ancient symbiosis between bison and the prairie. 

In Perman’s rotational grazing system, hundreds of cows at a time graze a fenced-in pasture intensely but briefly. Sheep are then brought in to munch whatever cows don’t eat. Animals are then kept off the grass for a year, allowing plants to regrow.

“The keystone species in this whole climate-change discussion is the cow,” says Perman. “You take the cow off the landscape, what do you suppose happens to the prairies and the grasslands?”

 After a hearty breakfast at Perman’s house, he and I hop on a four-wheeler for a bumpy ride out to the pastures. A punishing drought has turned grass in the region a crackling brown, but Perman points out many of the same drought-tolerant native plants that grow at Hamann’s places. His cows munch contentedly on a hillside. In a few days, he’ll open a gate and usher the herd toward a new, ungrazed paddock, where plants are up to several feet tall. “You know what it’s like on Black Friday when the store doors open?” he quips.

Perman’s way of farming faces stiff challenges. It’s hard work—the 66-year-old rancher told me he had already moved his herd, which numbers more than 1,000 cows, “at least a dozen times” since May—and ranchers are aging, often with no one to take over their farms. Beef consumption has steadily declined in the U.S. from its peak in the mid-1970s, and the government doesn’t subsidize grass-fed cattle the way it does crop farming.

“There’s much less of a safety net for raising cattle than there is for commodity crop production,” says Martha Kauffman, managing director of the World Wildlife Fund’s Northern Great Plains program.

For example, this year’s drought is pushing hay and feed prices up, forcing many ranchers to sell off animals. Drought-stricken corn and soybean farmers won’t feel the same pain, because nearly all of them buy federally subsidized crop insurance. The government spends more than $6 billion annually on crop insurance subsidies.

Perman would know, as he sells crop insurance, too. He launched the side business in 1985, in part so his son could take over the ranch and earn a living; the cows don’t provide enough income for the two of them and their families. The insurance Perman sells, he says, creates an incentive to grow crops even in places where they shouldn’t be—in soil that’s too wet or too dry, for example, or too salty or steeply sloped.

After leaving Perman’s ranch, I see the results from my drive along the long, straight roads north of Aberdeen, South Dakota. Field after field with anemic corn no more than a foot high, or shriveled soybeans, rise from salty white soil that until recently grew lush grasses.

 The battle to save grasslands has forged unlikely alliances. Ranchers like Perman and conservationists like Toay agree that to conserve grasslands in places like the Prairie Potholes, cattle ranchers need better financial incentives. Ducks Unlimited, for example, helps ranchers take advantage of federal programs that help pay for fencing. The Audubon Society is supporting a new venture to market beef from cows that spend their lives on grass—as opposed to being fattened on corn at a feedlot—in hopes of preserving grassland bird habitat.

The goal is to make responsible cattle grazing as attractive and rewarding as growing crops. “If we negatively impact the livestock industry, we will lose more grassland,” says Toay. “It’s a pretty simple, direct relationship.”

 To be sure, cattle have plenty of detractors. Cows burp methane, a powerful greenhouse gas, and in the tropics, forests are often cleared for pasture, making beef by some measures among the most climate-unfriendly foods available. But a growing body of research is revealing that not all beef should be lumped into the same climate bucket. Cows grazed in rotational systems like those employed by Perman and Hamann avoid deforestation and may emit less net greenhouse gas than those on feedlots, because grassland plants pull carbon out of the air and into the soil as they grow, offsetting emissions from the animals themselves. The exact balance depends on variables such as the local climate and how animals are managed, however, and scientists are still working out how to calculate the impact a particular cattle ranch has on the climate.

Rescuing grasslands requires Congress

In May, the Biden administration released a “progress report” detailing its plans to reduce agriculture’s carbon footprint. In a major move that could aid grasslands, the U.S. Department of Agriculture (USDA) boosted both the maximum number of acres and the rates it offers for its Conservation Reserve Program (CRP), which pays farmers to grow grass for 10 to 15 years on fields that previously grew crops. The USDA estimates the $2 billion-a-year program sequesters roughly nine million cars’ worth of carbon dioxide emissions per year.

But there are caveats: If CRP land is later plowed, which much of it is, a lot of the stored carbon is lost. And as havens for biodiversity, fields of planted grass can’t match native prairie that has never been plowed.

The USDA also expanded a relatively new program that pays ranchers to keep such prairie intact for 10 or 15 years. Perman, who has some land in the program, calls it “a step in the right direction.” Bill Hohenstein, director of USDA's Office of Energy and Environmental Policy, hopes the department can also help launch private-sector carbon markets tailored for ranchers that would pay for carbon sequestered in grasslands.

In April, Biden announced a commitment to conserve 30 percent of U.S. land and ocean ecosystems by 2030. What exactly such a “30 by 30” effort would entail is still unclear. One of the government’s primary grassland conservation tools thus far has been voluntary conservation easements, like the one Hamann has, under which landowners put land off limits to plowing in perpetuity in exchange for a one-time payment. Environmental groups are pushing a bill that would provide $350 million a year in new funding for easements and other incentives to keep grasslands intact.

The need for such biodiversity protections was underscored by a 2020 study by Lark and colleagues that found that between 2008 to 2016, new crop fields wiped out more than 200 million milkweed plants and destroyed some 138,000 potential waterfowl nesting sites.

Meanwhile, a fierce backlash to 30 by 30 has emerged among landowners in places like the Dakotas, many of whom don’t want to involve the government in what happens on their land. Dru Tosel, a farmer near Appleton, Minnesota, is one of them. Tosel plowed up roughly 55 acres of grass about five years ago to plant corn, and says he did taxpayers a favor, because he now pays a higher tax rate on the land. He has no interest in taking government incentives to return crop fields to grass, which he views as a waste of valuable land.

“I’m even thinking of putting in my will … you’ll never put this land in CRP or another government program,” Tosel says.

If grasslands are ultimately to be saved, advocates say, Congress will need to reform the programs that drive up crop prices. A bipartisan group of senators recently introduced a bill that could accomplish part of that by ending the ethanol mandate—a move that will be fiercely opposed by the agriculture industry. The crop insurance program, meanwhile, will probably get a hard look in the next Farm Bill, due in 2023.

Without such policy shifts, crops will likely continue to gain ground in their tug-of-war with grass, says Judge Jessop, project coordinator for the South Dakota Grasslands Coalition. “There’s just more money in the agriculture side of things than there is in the grass side,” he says. “I’m not against farmers. That’s the game they’re handed—and they’re playing it well.”

This story was produced in collaboration with the Food & Environment Reporting Network, a nonprofit investigative news organization.

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