Crops that don’t need to be planted every year can reduce soil erosion and nutrient runoff, but currently have lower yields. These researchers and businesses are working to fix that
In 2000, noted crop breeder Stan Cox was weary of the Sisyphean task of incorporating new disease resistance traits into wheat varieties. Fumbling to explain his malaise to a colleague, he recalls typing, “Don’t worry, I’m not going to do something crazy like work for the Land Institute.”
At the time, the Land Institute — a nonprofit that develops alternative farming practices they hope will displace destructive, industrial monocultures — was pursuing what many considered a quixotic endeavor: working with wild plants to create perennial varieties of wheat, legumes or sorghum. Such perennial crops could be harvested for multiple years without the need to cultivate the soil. By maintaining root systems year-round, there would be less soil erosion, more soil carbon and less fertilizer making its way into waterways— a problem that leads to harmful algal blooms and coastal dead zones.
Thirty seconds later, Cox deleted that sentence and instead wrote an email to Land Institute founder Wes Jackson, asking if he had any open positions.
“There was a time in the 1980s, when these efforts were in their infancy, that a lot of seasoned agronomists rejected the idea outright,” says Tim Crews, the Land Institute’s research director. Why, the thinking went, would anyone essentially start over at the dawn of agriculture to create perennial varieties of conventional crops using wild material — especially when it would take decades to match modern yields? Crews, rather, turns that on its head and questions the destructive impact of modern food production instead.
“Ecologically, it is shocking,” he says, likening annual tillage to a forest clear-cut. Breeding perennial crops may be a long-term investment but it’s one that promises dividends that annual cropping could never achieve.
There are two ways to develop perennial crops — domesticate a perennial wild species or create a hybrid of a perennial wild species and a domesticated variety. Currently Kernza — the trademarked name for the processed grain domesticated from intermediate wheatgrass, a perennial cousin of modern wheat — is the only perennial grain that has made its way into farmers’ fields and marketable products. But given that perennial grains were considered laughable 30 years ago, Cox, now the lead sorghum breeder at the Land Institute, and colleagues never expected to see any perennial variety make its way to fields and markets this soon.
The Land Institute, based in Salina, Kansas, remains the only U.S.-based research institute devoted to developing perennial grains and multi-species farming systems — but institutions around the world have now joined the effort.
As dozens of research institutions in France, Australia, Scandinavia and elsewhere pursue perennial grain crop research, the endeavors have pivoted from infancy to adolescence, says Crews. While each crop faces its own growing pains, he says, how perennial crops will mature ultimately depends on broader research partnerships involving, for example, academia, government and private investment.
Kernza is the poster child for the potential marketability of perennial grains. By this fall, Land Institute plant breeder Lee DeHaan expects Kernza will be produced on over 1,000 acres (405 hectares) by roughly 20 farmers — years earlier than he ever expected. What makes those 1,000 acres surprising is the fact that a typical Kernza yield is currently one-third to one-tenth of wheat, depending on where it’s grown. DeHaan had expected to spend many more years increasing yields before releasing seed to farmers — but product developers saw an opportunity to grow demand, which would bring more farmers on board, while DeHaan continues to improve yield over time.
Patagonia Provisions, the nascent food production company tied to the outdoor sales giant, pushed DeHaan to expand Kernza plantings to get commercial products on shelves. “It’s a chicken and egg situation,” says Birgit Cameron, senior director at Patagonia Provisions. “We have to show there is a market for products grown sustainably to incentivize farmers to grow it,” she says.
In the fall of 2016, Patagonia Provisions launched Long Root Ale — brewed by Hopworks Urban Brewery in Portland, Oregon — the first Kernza product on the market. Another outdoor and lifestyle apparel company, Askov Finlayson, partnered with Fair State Brewing Cooperative to also produce a beer made with Kernza. Several other products from different companies are currently in the pipeline, signs that the conversation with other potential product producers has changed, especially those with sustainability mandates. For example, cereal giant General Mills’ Cascadian Farms brand plans to launch a new, limited-edition organic Kernza-based cereal in the spring of 2019.
“There’s cooperation between companies we often think would be competitors,” says Laura Hansen, senior principal scientist at General Mills. If our overall goal is healthier soil and environment, she adds, then companies need to work together to build a supply chain.
Still, there is an element of risk when developing a new product around uncertain yields. Hansen says companies are aware they could create too much demand for the limited amount of Kernza currently available. “It’s a risk on everyone’s part, but we see the potential and the future,” she says.
To launch the cereal, General Mills has contracted for approximately 25,000 pounds (11,000 kilograms) — which, Hansen says, has been difficult to secure. Currently, the company is paying five to eight times more for Kernza than wheat to compensate farmers for the risks they are taking as they introduce a new crop, says Hansen.
The Land Institute aims to also domesticate perennial wild plants. Silphium integrifolium, a member of the sunflower family, is being domesticated for oil production, while they explore which legumes — for example lupines, vetches, and clovers — could be developed to serve as nitrogen-fixing crops grown together with grains to reduce the need for artificial fertilizers.
Domesticating a perennial wild plant is a long-term commitment of directed evolution. It takes decades of incremental change, but will ultimately find success. The alternative approach is to cross an improved annual variety and a wild perennial in hopes of combining long life with high yield. Although it seems like a shortcut, each cross can bring along unwanted traits that must be deleted by subsequent backcrosses.
Cox has developed a number of perennial sorghum hybrids by combining an annual species with a perennial weed called johnsongrass. The hybrid plants he’s developed over 18 years look less wild than when he started and more like one a farmer would grow. Crucially, grain size has increased over time. An annual variety seed is around 25–30 milligrams, while a johnsongrass seed is roughly 3 milligrams. Now, Cox says, the Land Institute’s largest perennial hybrid seeds weigh in at 18–21 milligrams.
“It’s approaching something useful as a cereal grain,” he says.
There are formidable, crop-specific challenges with both approaches. The yield of Kernza, for example, goes up from year 1 to year 2, then tends to go down over consecutive years. Silphium started with pretty high yields, says Crews, but native disease and insect herbivores have been an unexpected trouble spot, so breeders are now working to incorporate pest resistance and increase the use of crop diversity to reduce pest pressure.
Farmers are eager to get their hands on the most advanced wild-hybrid cross, PR23, or perennial rice 23, developed at Yunnan University in China, due to the comparable grain size and yields as annual rice — with significant labor savings. The biggest challenge was mitigating the trade-off between strong rhizomes, the underground stems that form new shoots each year, and low fertility.
“The mantra that we have to maximize yield is a huge barrier to developing perennial grains.” Sieglinde Snapp
Profitability remains a paramount challenge. Many groups are exploring the use of perennial grains as both forage and grain — potentially the key to their profitability. Researchers at Wagga Wagga Agricultural Institute in New South Wales, Australia, keen to get multiple uses out of one crop product, have the largest perennial wheat plantation in the world, at 2 hectares (5 acres) at the Cowra Agricultural Research and Advisory Station.
It is a proof-of-concept study to test whether perennial wheat hybrids could offer a novel forage option for grazing cattle and sheep. The research group will be the first in the world to assess meat quality of sheep grown on a perennial grain diet, says Richard Hayes, a researcher at Wagga Wagga.
Sieglinde Snapp, an agronomist at Michigan State University who has studied perennial wheat and pigeon pea, says for perennial grains to become commercially viable on a large scale will require a massive research investment.
To date, the U.S. Department of Agriculture has not dedicated research funding to breed perennial grains. The agency has invested only around US$2 million in about 10 different related projects over the past decade or so — most often when groups successfully proposed studying whether perennial grains could improve sustainability, for example, by reducing greenhouse gases or boosting soil health.
Even though there’s no question that organic perennial cropping systems will build more soil organic matter and quell nutrient leaching, “there’s still only so much political will” to develop these systems, says Snapp. “The mantra that we have to maximize yield is a huge barrier to developing perennial grains.”
Over two decades, DeHaan has made greater than 10 percent gains in Kernza yield over every three-year breeding cycle. Still, he says commercialization is a risky path at this point — one he wouldn’t have chosen without industry backing. But he acknowledges that it has raised consumer awareness, offered farmers an incentive to figure out how to grow Kernza and given the Land Institute’s work a legitimacy they haven’t seen until this point.