Opinion: A Magic Grain Goes Mainstream
The announcement didn’t make many headlines: The US based food company General Mills will invest into Kernza®, a perennial wheat grain. For anyone worried about soil health, climate change and the implication this will have on our ability to grow food Kernza® is – if you’ll pardon the pun – the best thing since the invention of sliced bread.
The first products containing Kernza® which is described as a flavourful, nutty grain, should be available in US supermarkets early next year. And the decision by General Mills to support this grain deserves big headlines. Kernza® is also the story of ancient grass lands, an ingenious idea and the patience and perseverance of dedicated scientists and plant breeders.
I encountered the first Kernza® plants in October of 2013. They grew on a test plot of the Land Institute in the middle of Kansas and looked rather unremarkable. ‘In July Kernza® looks like ordinary wheat’, said Tim Crews, director of research at the Land Institute, the difference between wheat and Kernza® lies under ground: wheat is an annual plant, it has to be grown from seed every year, which leaves the roots only a short time to develop. Kernza® is a perennial plant, after the harvest the plant stays in the ground, which allows Kernza® to grow a deep, extensive root network. The plants will yield a crop year after year after year...., And because the soil is not disturbed by ploughing, organic matter builds up, soil quality improves and more carbon can be sequestered from the air. Like a pasture, a field of Kernza® is a carbon sink!
Not pastures but prairies made Wes Jackson, the founder and long time director of the Land Institute think about soils. Some 50 miles east of the Land Institute lies the Konza Prairie, a 3,500 ha nature reserve, where visitors can still get a glimpse of what large parts of the North American continent look like before the invention of the steel plough and the arrival of farmers who transformed this ancient grassland into fields. The Konza Prairie is an amazing place, rolling hills covered by a sea of tall grasses swaying with the wind, serene and quiet but for the buzzing insects. Tall cotton wood trees provide shade in the dips where moisture collects. Somewhere here a herd of bison is grazing. Under the grasses lies a thick layer of black, fertile soil that built up over thousands of years. The grasses are like the tip of an iceberg, hidden beneath are the long, thick roots. At the Land Institute you can see images of the root network of prairie grasses next to that of wheat: the roots of the wheat look puny and anaemic next to those of the prairie grasses that are much thicker and reach into the ground at least three times as deep.
Once the prairie was ploughed up erosion began: year on year some more of the fertile soil was washed or blown away. About half of the humus that built up over millennia has been lost in less than two hundred years. Farmers, agronomists and environmentalists have been worried about soil erosion for a long time – but how to stop it? What if a grain like wheat were perennial and could develop roots as deep as those of its ancestors, the prairie grasses? It was this vision that led Wes Jackson to found the Land Institute and start a breeding programme for perennial grain crops.
Scientists at the Rodale Institute, a renown organic research facility in Pennsylvania had already identified promising looking prairie grass varieties. At the Land Institute the breeders started to select, cross breed, select again, cross breed and select ... The work on what today is called Kernza® started around 2005. A wild grass was selected for high yields, large kernels, shattering resistance, synchronisation of maturity, uniformity, disease resistance and rooting depth, and then crossed with ordinary wheat. Tim Crews says it’s extremely difficult to truly establish the perennial quality in a plant as it is encrypted on several genes – which also means that it is too complex a quality to achieve through genetic engineering. At present the kernels have roughly 1/3 of the size of wheat and can be milled. New York Times food writer Mark Bittman found Kernza® bread to be ‘delicious’. Small breweries have been using it to make craft beers and bakers like it – Kernza® contains less gluten than ordinary wheat and its baking properties are somewhat similar to rye. On its own Kernza® flour can be used to make quick breads like muffins and pancakes.
Kernza® is ‘work in progress’, the breeders want to further improve the size of the kernels and increase yields, intercropping with legumes might increase its profitability, too. The Land Institute already works with the University of Minnesota and farmers in the northern Midwest and the Skagit Valley in the Pacific Northwest, an area that is known for its excellent soils and climate being particularly suited to growing grains. With General Mills, Kernza® will become more widely known among growers and producers. With more demand, a bigger market, more money and resources for research Kernza® products will hopefully become a staple on supermarket shelves not just in the US but also in Europe – a tasty grain that improves the soil and sequesters carbon while it grows. Looks like with Kernza® we can truly have our cake and eat it!