For 12,000 years, human agriculture has cultivated grains that are replanted every year, at enormous environmental cost. Kernza represents a new way forward.
On an August morning in Minneapolis, I sat at a wooden table inside the Birchwood Cafe, a bright, cheerful restaurant a few blocks from the Mississippi River waterfront, tasting an éclair as attentively as I could. The flavor I wanted to detect was partly obscured by more conspicuous ingredients: a high-pitched, jammy blueberry glaze painted across the top of the pastry, and the sweet song of a yellow corn custard. But beneath that, there was a subtle and earthy background note: the grain. The pastry was made in part from wheat flour, but you could detect another ingredient as well—something that tasted like nuts and crackers, coffee and grass. That flavor came from Kernza, a grain almost entirely unknown to the human diet until a few years ago, when the Birchwood became one of the first places in the country to serve it, and the first to list it on the menu.
Tracy Singleton, the café’s owner, likes getting people, including herself, to try new and improbable things. More than two decades ago, when she was in her early 30s, she inherited about $10,000 from her grandfather, quit her waitress job, took out a loan, and launched the Birchwood. Her café grew into one of the city’s best-known institutions, a place for Midwest-grown ingredients both gourmet and unpretentious. “We’ve been telling farm-to-table stories before people were using the term ‘farm to table,’” she told me.
So she was undaunted when Helene Murray, an agronomist at the University of Minnesota, asked, in early 2013, if she wanted to try serving up Kernza, even though no one in the kitchen knew exactly what to do with it. “It was like, ‘Wow, this a pretty big honor,’” Singleton recalled. “Yeah, we’ll put it in some food and we’ll talk about it.” About two weeks later, Murray parked her car next to the Birchwood, and she and Singleton hoisted a 50-pound bag of the new grain out of the trunk and through the café’s front door.
Kernza is sometimes called a “perennial wheat.” Birchwood has touted it as “the wheat of the future.” But it’s a separate species. Chestnut-colored, skinnier, and more irregular in size than wheat berries, Kernza yields a little under a third as much in the field as conventional wheat. But it has one major advantage over the grain that helped launch human civilization: a long life span. Wheat is an annual; it dies every year after it sets seeds, and farmers have to replant it again and again. Kernza lives on, season after season.
The word “grain” has many definitions, but it commonly refers to any plant that humans eat and that’s also part of the botanical family of grasses. Three grains provide about half of the world’s calories: corn, wheat, and rice (the only one of the three that is occasionally cultivated as a perennial in the tropics). In the United States, about 46 million acres of land are covered with wheat and 91 million with corn, a combined area bigger than New Mexico. Mostly, these grains are planted in monoculture—one variety to a huge field—and cultivated with the help of fertilizers, herbicides, and pesticides, as well as the kind of precision and efficiency you’d expect on a factory floor. This method of farming has made it possible to cheaply produce food calories for hundreds of millions of people; raise vast populations of cattle, pigs, and chickens; and develop enormous markets for other grain-based products, including ethanol. (About 40 percent of American-grown corn in 2016 was turned into ethanol; 37 percent was used to fatten livestock or ended up damaged or miscounted; and a minuscule fraction entered the human diet, mostly as corn syrup.)
But these farming methods also entail major sacrifices. Growing grain this way requires huge amounts of fossil fuel to power farm machinery and to make synthetic nitrogen fertilizer (accounting for as much as 3 percent of the world’s carbon emissions). And every time you till and replant, you loosen and tear up the topsoil. As a result, millions of tons of soil erode into the nation’s waterways every year, carrying pesticides, herbicides, and fertilizers with them, contributing to a “dead zone” in the Gulf of Mexico, and polluting waterways all over the Midwest.
While Kernza has the taste of a cereal, it has the habits of a prairie grass. It sinks 15-foot-long roots into the soil and banks nutrients and carbon as organic matter. It produces edible grain for five years, during which time it requires little or no tilling and less fertilizer than wheat does. To create and grow such a grain has been the dream of a group of scientists and sustainable-food advocates for four decades. According to its proponents, if Kernza succeeds as food, it could be the start of a revolution to save soil and fight climate change. But until recently, perennial crops seemed like an unimaginably distant prospect, requiring many generations of crossing and recrossing to arrive at anything that would function at the scale of modern agriculture. Then, a few years ago, Kernza breeding trials at the Land Institute in Kansas and the University of Minnesota began to make rapid progress, and the research caught the eye of big companies like the Minneapolis-based General Mills and Patagonia, which has a food division called Patagonia Provisions.
To make Kernza palatable to such corporations, the researchers needed trailblazers—people who understood the business of food and would try running Kernza from the farm, through the mill, into the kitchen, and onto the plate. Singleton likes a good story, and she found the tale of Kernza captivating. If there was going to be a movement to revolutionize food, she wanted to be a part of it.
The 12,000-year history of grain agriculture is essentially a long-running set of experiments to turn grass into something that humans could reliably harvest and eat. Humanity’s first crops—including barley and two varieties of wheat called emmer and einkorn—started, of course, as wild plants. Hunter-gatherers probably sought those plants for their fat, nutritious seeds. Around 10,000 bc, humans began to cultivate them, and the abundant calories those plants produce made it possible for civilization to flower in the Middle East’s Fertile Crescent. But in choosing to cultivate and breed those seeds, the first farmers committed human society to a long dependence on the annual grain, a crop that dies at the end of each season and is born again the next from new seed. In order to germinate successfully every year, the seeds of annuals need free space on the ground, away from predators and competing weeds. For centuries, the primary means of creating that space has been tillage: churning the soil until it’s mostly bare, first by hand or with tools, then with animal-drawn plows, and more recently with heavy machinery like tillers and cultivators.
Across a large area, the results of plowing and tilling can be disastrous, as became clear in the United States in the 1930s, when drought turned the heavily plowed soils of the Great Plains into the nightmare known as the Dust Bowl. From that decade forward, the US government vigorously promoted soil-conservation measures, including methods like windbreaks. Annual erosion rates have dropped decade after decade, but the United States still loses soil 10 times faster than nature can replace it.
More recently, scientists have also discovered that activities that churn up the soil, especially tilling, play a role in climate change. Soil holds nutrients, minerals, and carbon, bound up into organic matter by the various tiny animals, fungi, and microorganisms that inhabit it. When you churn it up, some of that soil carbon breaks down and escapes into the atmosphere, adding to the load of carbon dioxide that is now altering the planet. One recent study estimated that agriculture, over the millennia, has contributed about 133 billion metric tons of carbon to the planet’s atmosphere. “I talk about an intensive tillage event as the combination of a tornado, a hurricane, an earthquake, a tsunami,” says Don Reicosky, a retired US Department of Agriculture soil scientist. “There’s a big burp of carbon dioxide that goes out with that.” In the last few decades, people like Reicosky have urged farmers to cut back on the wasting of soil and the dumping of carbon through a method called “no-till,” which involves planting seeds beneath the remains of the previous season’s crops. But no-till farmers often turn to herbicides to keep the weeds down.
If more of the world’s daily bread came from perennials instead of annuals, there would be less need to clear a path for seedlings every season. Perennial farming could build the soil year by year instead of tearing it apart. Starting as early as the 1920s, both American and Russian scientists tested a few lines of perennial wheat, hoping to save farmers the cost of replanting new seed every year. But the dream of a perennial grain revolution didn’t gather momentum until 50 years later. In 1977, Wes Jackson, co-founder of an agricultural-research organization called the Land Institute, was strolling through the Konza Prairie Biological Station in northeast Kansas—several thousand acres of grassland that look much like the Great Plains did before they were plowed up for agriculture. Jackson had just read a report from the US comptroller general showing that more than five tons of topsoil per acre were eroding from the average grain farm annually. And he wondered: Why couldn’t a farm look more like this prairie, with a motley collection of annuals and perennials growing side by side? The prairie didn’t need to be replanted year after year, and no one needed to till the soil to get the grasses to grow. But to make a farm modeled on a prairie, with food plants instead of wild ones, you’d have to rewrite agriculture basically from scratch. Jackson believed that his vision was possible, but he imagined it would take 50 to 100 years of plant breeding—ambitious when you consider how many millennia it took to create the grains we have now.
In the early 1980s, Jackson persuaded Robert Rodale (son of J.I. Rodale, founder of the Rodale Institute, one of the oldest organic-farming organizations in the country) to search for a perennial that could substitute for wheat. The Rodale Institute rooted through seed banks and tested nearly 100 candidates gathered from around the world, before landing on a species called Thinopyrum intermedium, a wheatgrass first collected from Turkey and Afghanistan. Relative to other wild grasses, this one had seeds of a decent size and shape—not shrunken, discolored, or bristling with the needle-like awns that can make grasses hard to harvest and thresh. And there was some evidence that it may have been eaten by humans several millennia ago.
The breeding experiments proceeded on a small scale until 2001, when Lee DeHaan joined the Land Institute’s staff. He had been an admirer of Jackson’s since his teen years, when his father, a farmer, heard the scientist give a talk in Minnesota. After that, Lee wanted nothing more than to devote his career to perennial agriculture. In 2003, he launched a large-scale program at the Land Institute to convert T. intermedium into a functioning grain crop called Kernza, a play on the name Konza. It was the same year that the Human Genome Project was completed. Kernza’s DNA has never been genetically engineered; its genes get reshuffled via the scattering of pollen, from the male parts of flowers onto the feathery, sticky female parts. But advances in genomics—the -sequencing of DNA—over the last 15 years have made it far easier to tweak Kernza. Almost all of the grain’s genome has now been mapped. Once breeders have a genetic blueprint, they can track down the genes that control particular traits and select individuals with genetic stock that codes for, say, fat seeds or resistance to disease. In the last decade, Kernza’s potential yield has gone up by 10 percent annually. In 2011, the Land Institute began collaborating with the University of Minnesota to research the grain. Kernza has since become a major initiative at the university, spanning several academic departments, including plant genetics, agronomy, and food science.
This year, General Mills offered the university half a million dollars to study several aspects of Kernza, including how it might help store carbon and organic matter in the soil. The company wants to reach what it calls “sustainable emission levels” by 2050 and hopes that Kernza will be part of the means to get there. Meanwhile, the Land Institute, the University of Minnesota, and their partners are trying to hammer out other varieties of perennial crops: a rice being tested in China, an oilseed akin to canola, a flaxseed native to North America. And a small number of research programs into perennials have been started around the world. The Bread Lab, a program of Washington State University, has been developing its own version of a wheatlike perennial called Salish Blue. The result of a 20-year effort to cross annual wheat with perennial wheatgrass, Salish Blue lives for about two years, and farmers in northwest Washington are now beginning to grow it in their fields.
About four miles northeast of the Birchwood Cafe, you can find Kernza in an ongoing state of metamorphosis, in test plots at the University of Minnesota’s Agricultural Experiment Station. When I visit the plots, it’s a clear blue afternoon at the end of the summer growing season, when corn ears are heavy with ripe kernels. The Kernza is congregated in a half-acre plot amid a patchwork of experimental fields of corn and soybeans. In comparison with its neighbors, the Kernza looks rangy and feral, with stems at various heights and leaning at odd angles. But up close, it’s a handsome plant: golden-headed, with bluish-green stems gathered in bunches like a prairie grass, and sprinting to four or five feet tall.
Prabin Bajgain, a university plant geneticist, and his colleague, Jacob Jungers, an agronomist, lead me into the center of the field, where I notice that half of the bunches have had their spikes lopped off, and a few of these are streaked with orange paint. The paint marks the winners, those that have been weighed and measured for seed size and yield and could be used to develop future batches of Kernza. In August, Bajgain took seeds from about 900 plants back to the lab, selected the best ones, and plotted out pieces of their genetic code. This analysis helps the breeders put together a set of statistical predictions about which plants will be the hardiest and best-yielding in order to narrow down the choice of which ones to replant the following year.
Every year, the transformation of Kernza seems stunningly fast, at least on the slow time scales that plant breeders are accustomed to. Since 2001, the potential size of a Kernza seed has doubled, and scientists hope to lengthen its productive lifespan from five to 10 years. Jungers plucks a spikelet from the grass head, peels a few of the kernels out of their husks, and holds them out in his palm. They are nearly as big as grains of rice, although I’ve seen some about the size of caraway seeds.
Then, in a sudden gesture, Bajgain leans forward and flings his hands up and along the stems in one of the bunches. When his fingers hit the spikes at the top, a few grain flowers leap into the air in a delicate cascade. But most of the spikelets cling to the stem. This is one of the markers of a domesticated plant: Instead of casting its seeds to the wind, it waits for a human hand or a combine to strip the grain from the plant. Just two years ago, Kernza grains were flighty. “You could touch them, you shake them; they just dropped,” Bajgain says. “But these, you go like this”—swiping his hand over another stalk, which barely sheds any seeds at all—“and, man, it’s so nice.”
To date, the best-known endeavor to reimagine farming has been the organic-food movement. Every year, organic agriculture branches further into the fruits and vegetables market, but it has made far fewer inroads into the market for grains. Produce accounts for 43 percent of organic sales, bread and grains just 9 percent. Making farming more sustainable is a more complicated endeavor for grain farmers—whose product interacts with a complex supply chain before reaching consumers—than it is for fruit and vegetable farmers, who can reach consumers with organic produce directly at farmers’ markets and grocery stores. Kernza, which, like all plants, can be grown organically or conventionally, represents a different approach to sustainable farming. But to make it work, you must navigate a far-reaching system of milling, processing, fermenting, and baking.
The role of the Birchwood Cafe, as tester and trailblazer, was to run Kernza through a supply chain—literally from farm to table—and find the obstacles along the way. These became apparent from the first moment. For one thing, the kernels are too small to grind into flour with a conventional mill. The first batch to reach Birchwood in 2013 hadn’t been milled, so the chefs tried tossing the whole grain, cooked, into salads and pancake batter. Customers devoured the results. The university sent the next batch to a farmer in Wisconsin who owned a specialized mill attached to a bicycle; he pedaled many pounds of Kernza into flour, and the Birchwood chefs tried it in bread and pastries. Kernza is lower in the gluten that makes wheat dough flexible enough to rise; substitute it for wheat in a bread recipe and you could end up with something about as dense and unappealing as cardboard. But the chefs played with the moisture content of the dough, teasing out an appropriate texture.
The supply of Kernza has been inconsistent: In Minnesota, only a handful of farmers near the Canadian border grow it. The restaurant has run out for weeks at a time. Despite all this, enthusiasm for Kernza is on the rise. Customers often ask the Birchwood staff where they can buy their own bags of grain or flour, though Kernza is not yet available to the public in either form.
Meanwhile, the university has given several other local food vendors the chance to experiment with the new grain. A local microbrewery called Bang now makes a Kernza beer named Gold. This past summer, a Minneapolis pasta company called Dumpling & Strand sold Kernza noodles at a farmers’ market. Elsewhere in the country, a San Francisco restaurant aptly named the Perennial serves a bread made with the new grain, and a baker in New York has concocted a 75 percent Kernza loaf. Some major companies are also ready to take the leap. A year ago, Patagonia Provisions and the Hopworks Urban Brewery released a beer called Long Root Ale, brewed in Portland and available in some Whole Foods stores.
Last year, a small artisan mill called Baker’s Field Flour and Bread opened in the Northeast Minneapolis Arts District. It now supplies Kernza flour to Minnesota -businesses turning it into food. Last fall, General Mills asked Steve Horton, the owner of Baker’s Field, to mill 250 pounds of it. “I tried it in almost every product that we make that uses flour,” says Laura Hansen, the company’s senior principal scientist. General Mills plans to launch a “ready-to-eat cereal” made from Kernza in the next year, as part of its Cascadian Farm Organic line.
If General Mills moves ahead with Kernza, contracting farmers to grow a steady supply of it, that will change the game. But none of the small food businesses I spoke with were worried about the big food company’s involvement—not even Horton, who admitted that his operations were too small for him to continue as the go-to Kernza miller. “We need agribusiness to be involved,” he said, if Kernza is ever going to succeed.
A day after I visited Birchwood, I followed the trail of the Kernza éclair to the Minnesota State Fair, one of the largest such events in the nation. The éclair was one of the fair’s featured foods this year, and it had sold out -every day so far. Inside the fair’s Agriculture Horticulture building was a booth for Forever Green, a University of Minnesota program promoting perennial agriculture. Don Wyse, a bearded, white-haired professor of natural resources, stood beside several sheaves of Kernza stems, each the size of a pillar. “Organic hasn’t changed the Midwest much,” Wyse told me. “Vegetables don’t cover millions of acres. We have to look at those things that cover millions of acres.”
For years, a segment of the food movement has clung to a nostalgic view—back to the land, back to heirloom varieties—while some sustainable-food advocates have distanced themselves from the conventional grain farming that ranges across the Great Plains and the Midwest. But in a time of climate change, it’s possible that farming needs a different kind of makeover, bearing in mind the realities of Big Agriculture and the humble grains that power most of the farming sector.
Several millennia ago, wheat changed the course of civilization. Perhaps it’s time for another rewrite.