How year-round crops could reduce farm pollution in the Mississippi River

Don Wyse’s field of winter barley used to be mostly empty in the spring.

Eight years ago, just a tenth of the grain would survive the winter in this experimental field in St. Paul. But this year, after repeatedly refining the plants’ genetics, the field was flush with swaying, pale yellow grain heads.

The winter is the first hurdle that researchers at the University of Minnesota’s Forever Green Initiative must get over as they attempt to breed new crops that can cover farm fields year round – and in the process, help water quality across the state.

For years, Minnesota has struggled to reduce the farm pollution from fertilizers and other sources that runs into streams, lakes, the Mississippi River and eventually, the Gulf of Mexico.

Wyse, a crop scientist who founded and now co-leads Forever Green, said he watched for years as all the funding for farm pollution research went into describing the problem. “There wasn’t a very big investment in solutions.”

So crop breeders at Forever Green are working on 16 perennial and winter annual crops to suck up that nutrient pollution before it escapes. Food scientists and marketers with the program are trying to develop uses for these crops and hopefully, provide new revenue for farmers, too.

Perennial crops are not a new idea – groups like the nonprofit Land Institute, in Salina, Kansas, have been promoting the concept for decades. It holds the trademark for Kernza, a perennial grain it is developing in partnership with Forever Green scientists.

Lee DeHaan, the lead scientist for Kernza domestication with the Institute, said UMN’s work on perennial grains was “leading this push nationally and internationally.”

But challenges still remain in the chicken-or-egg problem of developing a market for these crops. For the crops to be used in large-scale products, there needs to be a lot of production; but for farmers to bet on them, they need to be convinced there’s a market.

Emily Heaton, a professor of crop sciences at the University of Illinois Urbana-Champaign and director of the Illinois Regenerative Agriculture Initiative, said the data supports the work Forever Green is doing.

Putting perennials on just 10 percent of croplands would make an impact on environmental measures like water quality – but scaling up the crops to that extent is still a challenge, she said.

“The strategies are not rocket science,” said Heaton, who has also done research of her own on growing the grassy perennial miscanthus. “That doesn’t make implementing them easy.”

Carried in the water

In the fertile fields of the Midwest, corn and soybeans dominate: the two annual crops covered 63 percent of Minnesota’s 25 million farm acres in 2021, according to the U.S. Department of Agriculture. In other states, the proportion is even higher – they cover 76 percent of farmland in Iowa and 80 percent in Illinois.

In these row crop operations, typically, farmers are tilling and planting seed in the spring, harvesting in the fall and leaving that ground bare until the next growing season.

Falling rain easily washes nutrients out of these fallow fields and into nearby waterways. Phosphorus that flows with eroding farm soils feeds algae in Minnesota’s lakes; nitrogen seeps down into groundwater, fouling rural water wells.

“It’s this wicked problem that’s choking our rivers,” said Whitney Clark, executive director of Friends of the Mississippi River. There are “too many acres of leaky, annual row crops.”

Nitrogen also travels further, down the Mississippi River to the Gulf of Mexico, where it helps to fuel an annual algae explosion and die-off that saps oxygen out of a massive “dead zone.” This year, the National Oceanic and Atmospheric Administration forecast that the dead zone would be 5,364 square miles, or nearly the size of the state of Connecticut.

The latest action plan to shrink this dead zone, from 2008, recommended each state along the river basin to reduce its nitrogen and phosphorus pollution by 45 percent. But despite some states’ best efforts, the levels remain high.

David Wall, a research scientist with the Minnesota Pollution Control Agency, said the state has shrunk phosphorus amounts between 20 and 35 percent, mostly from improving sewage treatment plants and some cropland management measures, among other measures, he said.

But nitrogen readings in rivers around the state show almost no reduction – and in several cases, a slight increase, Wall said. Most of that nitrogen is coming from farmlands that are mostly covered with row crops.

A solution, then, is to keep plant roots in the ground longer, where they will stabilize the soil and suck up nitrogen before it escapes.

Even in the winter, when perennial plants appear dead above the ground or are covered with snow, under the soil, their roots are still alive, said DeHaan, who has been working with the Forever Green program to develop Kernza.

The thick, grasslike plant produces well for about three years, popping out of the ground each spring and maturing for harvest by late summer or fall. By staying in place year round, peer-reviewed research from Forever Green has shown that it captures 99 percent of the nitrogen that would otherwise escape compared to annual corn, said Jake Jungers, DeHaan’s counterpart at Forever Green. A separate study conducted in Michigan that included DeHaan as an author showed that Kernza captured 86 percent of nitrogen.

“The only way to keep nitrogen from flushing through the soil is to have roots intercept that nitrogen,” DeHaan said.

In the field

Right now, Kernza plants are producing just 20 percent of what wheat plants do on the same acreage in field tests in Kansas, DeHaan said.

On UMN’s fields in St. Paul, breeders are working to solve that problem. Scientists painstakingly collected pollen from perennial plants and applied it to traditional, annual wheat. The hybrids are growing now, and the hope is that they will have both the perennial qualities of Kernza and the higher grain amounts of regular wheat.

Success or failure won’t be apparent until next spring, Wyse said as he stood in front of a patch of green, swaying wheat grasses that resulted from the crosses. Only if they emerge again, will breeders know whether the plants are truly perennials.

While the work is still painstaking, researchers have been greatly aided, in recent years, by new technology. The speed of genome sequencing has sped up crop science – once breeders identify a gene for a specific trait like winter hardiness, for example, they can sequence all of the different varieties they produce and remove any that lack the desired gene before they’re planted.

Shari L. Gross

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Shari L. Gross, Star Tribune

Take pennycress, a common roadside weed that breeder David Marks is trying to make into a major winter staple crop. Marks is so optimistic about the potential for pennycress to produce edible seeds that he has the plant’s light-green likeness tattooed on his left forearm.

Marks has plenty to do to make the crop ready for market. The flat, circular seed pods have to be made more durable so they don’t shatter open before harvest; thick seed coats must be thinned, so errant seed doesn’t survive in the soil longer than a farmer might want them there; and unsafe-to-consume erucic acid has to be eliminated from the seed oils.

Marks is excited about the crop’s potential as a winter annual not just because it will stop fertilizers from entering the water, but because it expands the growing window, at a time when the pandemic and war in Ukraine have destabilized the globe.

Marks worries that the next disruption “will be a threat to our food security,” he said. “I’m thinking of the future of what’s coming next.”

Building the market

Of all of Forever Green’s different crops, Kernza is perhaps the best known – and the most advanced in the process of actually being made into consumer products.

And for these crops to actually make a difference, they need to be adopted on a grand scale, Wyse said.

“We have to have big markets to get enough of these plants on the landscape to protect the Mississippi River,” Wyse said.

There are a few products on the market right now, like a Kernza cereal sold in Whole Foods stores by Cascadian Farm, a General Mills brand.

But growers said the Kernza they grow isn’t selling as fast as other crops.

Some state money has recently been budgeted to help with this scale-up. In addition to $763,000 in funding for the actual crop breeding, this year a bipartisan group of Minnesota lawmakers allocated $500,000 to help fund the supply-chain businesses that take the grain from fields to store shelves.

Developing the supply chain has required intense work, said Christopher Abbott, the president of Perennial Pantry. The startup is focused on selling foods that use perennial and cover crops, and began in 2020.

Kernza has to go through extensive cleaning after harvest, and it takes about ten times longer than conventional wheat, Abbott said. After that, his company had to experiment with how to actually use the grain, which has a higher bran to starch ratio than other wheat.

One of Abbott’s favorite products is a Kernza cracker, which he described as buttery and flaky; it took 80 iterations to get right, he said.

So far, most of the customers who buy Perennial Pantry’s flour, crackers, pancake mix or pasta are familiar with the environmental story behind the products, Abbott said.

“I wish that would take it further out into the world, but I think realistically for the reasons people buy food, taste and health usually lead the way,” Abbott said.

He said the company has access to enough Kernza for the products it makes right now. And while farmers want to grow more of the crop, and profit from it, the market is at a delicate tipping point. Jungers, Forever Green’s Kernza breeder, said if demand increases sharply, production may not be up to the task.

“What worries me is that one day General Mills is maybe going to launch a product and it requires millions of pounds of Kernza, and there’s a frantic effort to grow that,” Jungers said.

The early adopters of the crop, though, are eager to make the plantings work.

Anne Schwagerl, a farmer in the western part of Minnesota near Beardsley, said she’d been “standing on the sidelines, watching the Forever Green crops excitedly for several years.”

But her Kernza crop has required some adjustments. Schwagerl planted 40 acres of Kernza in 2020, said harvesting now takes two passes; the seed heads of the wheatgrass must be lopped off and left in the field to dry for a few days before they can be collected.

Schwagerl said the novel grain fits well in her organic operation which also grows soybeans, corn, wheat and oats.

But because of the new market, she wasn’t able to sell the grain she first harvested in the fall of 2021 until the following spring.

“The Kernza, we had to store a lot longer than with our corn or soybean or oats crop,” Schwagerl said.

There have been benefits, too. This spring, farmers struggled to get their seed into the ground in much of the state, as the cold, wet season delayed planting.

Schwagerl didn’t have to worry about planting; her Kernza grass was already there, with roots several feet deep.

This story is a product of the Mississippi River Basin Ag & Water Desk, an editorially independent reporting network based at the University of Missouri School of Journalism in partnership with Report For Americaand funded by the Walton Family Foundation.

Walton has also funded The Land Institute, a source in this story.