A perennial grain is a grain crop that lives and remains productive for two or more years. Rather than growing for only one season before harvest, like most grains and annual crops, perennial grains grow year after year. While many fruit, nut and forage crops are long-lived perennial plants, all major grain crops presently used in large-scale agriculture are annuals or short-lived perennials grown as annuals. Scientists from several nations have argued that perennial versions of today's grain crops could be developed and that these perennial grains could make grain agriculture more sustainable.
The 2005 Synthesis Report of the United Nations’ Millennium Ecosystem Assessment program labeled agriculture the “largest threat to biodiversity and ecosystem function of any single human activity.” Perennial grains could reduce this threat, according to the following logic:
- Most agricultural land is devoted to the production of grain crops: cereal, oilseed, and legume crops occupy 75% of US and 69% of global croplands. These grains include such crops as wheat, rice, and maize; together they provide over 70% of human food calories.
- All these grain crops are currently annual plants which are generally planted into cultivated soil.
- Frequent cultivation puts soil at risk of loss and degradation.
- This "central dilemma" of agriculture in which current food production undermines the potential for future food production could be escaped by developing perennial grain crops that do not require tilling the soil each year. No-till technology enables short-lived (annual) crops to be grown with less intense tillage, but perennial plants provide the most protection for the soil.
Perennial Grains in the Marketplace
Kernza®, an intermediate wheatgrass, has been under development for use as a grain crop since the 1980s. Since 2001, the nonprofit organization The Land Institute’s Dr. Lee DeHaan has led development of the crop, coining the trademarked name Kernza in 2009.
Recently, work on Kernza has rapidly expanded to include more than 25 lead scientists in diverse fields working on three continents. This international team has developed growing techniques and dramatically improved traits such as shatter resistance, seed size and yield, enabling the crop to now be produced and marketed at a small scale. US Institutional Kernza research partners now include the University of Minnesota, the University of Wisconsin, Madison, Cornell University, Ohio State, Kansas State, and numerous international universities in Canada and Europe, including the University of Minnesota, Lund University, and ISARA.
As the first perennial grain crop grown across the northern United States, researchers hope that Kernza will help dramatically shift agriculture practice, making croplands multifunctional through the production of both food and ecosystem services1.
The Land Institute developed the registered trademark for Kernza® grain to help identify intermediate wheatgrass grain that is certified as a perennial using the most advanced types of T. intermedium seed.
Patagonia Provisions was the first company to develop a commercial retail product made from Kernza® perennial grain for the mainstream marketplace. Patagonia took a significant risk, breaking through the initial barrier to new product development and market entry with Long Root Ale.
The initiative and investment on the part of Patagonia Provisions to bring Long Root Ale to market helped pave the way for other partnerships and potential Kernza® products becoming more widely available to consumers.
Currently, there are a number of restaurants serving products made with Kernza®, including Birchwood Cafe in Minneapolis, The Perennial in San Francisco, Cafe Gratitude in the Los Angeles metro, and Avalanche Pizza in Athens, OH.
Hopworks Urban Brewery in Portland, OR and Vancouver, WA brewed Long Root Ale for Patagonia Provisions and has it on tap, in addition to the ale in four-pack cans being sold in Whole Foods in California. Bang! Brewing in St. Paul, MN has a Kernza® beer available, as does Blue Skye Brewery near us in Salina, KS.
Innovative Dumpling & Strand produces Kernza® pasta that they retail through Twin Cities-area farmers’ markets.
Additionally, Cascadian Farm plans to incorporate Kernza® into some of its foods, with expectations for products made with Kernza® available in retail markets by late 2019. Cascadian Farm’s commitment to purchase has spurred researchers and farmers to plant on commercial-scale fields versus the test sized plots currently being grown.
By providing year-round soil coverage and exceptionally large belowground carbon inputs from roots, farmers growing Kernza® and other perennial grains will:
- sequester more carbon
- reduce nitrogen and phosphorus contamination of freshwater and marine ecosystems, and
- reduce weed competition, minimizing tillage and herbicide applications.
With perennial soil cover, farmers stand to greatly reduce soil erosion, potentially turning agriculture into a soil-forming ecosystem, much like the natural ecosystems it replaced. Initial research suggests that due to extensive perennial roots, Kernza and other perennial crops may nurture beneficial soil microbiomes. The frequent soil disturbance required in annual crop production is disruptive to these microbiomes.
Deeper and more abundant root systems drive healthy soil. Scientific evidence documenting the ecosystem benefits of Kernza is accumulating. Research from other perennial systems such as pastures and perennial biofuel crops provide robust evidence of the potential benefits of a perennial grain like Kernza. For example, Paustian and colleagues recently published a paper in Nature titled “Climate-Smart Soils” that compares different landscape management approaches for increasing soil carbon sequestration. It is clear from their analysis that perennial grains would be a game-changer, as they could sequester carbon and maintain more cropland in production better than any alternative.
- Perennial rice
- Perennial sunflower
- Thinopyrum intermedium
- Plant breeding
- Food grain
- Subsistence agriculture
- The Global Inventory Project
- Perennial Wheat
- Perennial Sorghum
- Wagoner, P.; Schaeffer, J. R. (1990). "Perennial grain development: Past efforts and potential for the future". Critical Reviews in Plant Sciences. 9 (5): 381. doi:10.1080/07352689009382298.
- National Research Council of the National Academies. 2010. Toward Sustainable Agricultural Systems in the 21st Century. National Academy Press, Washington D.C. pp 249-251.
- Cassman KG, Wood S. 2005. "Cultivated systems". Chapter 26 in Millennium Ecosystem Assessment, Ecosystems and Human Well-Being: Current State and Trends. Washington (DC): Island Press. Chiras DD, Reganold JP, Owen OS. 2004 Natural Resource Conservation. Upper Saddle River, New Jersey: Prentice-Hall.
- Glover, JD, Reganold, JP. 2010. Perennial grains: Food security for the future. Issues in Science and Technology. Winter 2010:41-47.
- Cox, T. S.; Glover, J. D.; Van Tassel, D. L.; Cox, C. M.; Dehaan, L. E. R. (2006). "Prospects for Developing Perennial Grain Crops". BioScience. 56 (8): 649. doi:10.1641/0006-3568(2006)56[649:PFDPGC]2.0.CO;2.
- Ewel, J. J. (1986). "Designing Agricultural Ecosystems for the Humid Tropics". Annual Review of Ecology and Systematics. 17: 245–271. doi:10.1146/annurev.es.17.110186.001333
- "Kernza® Grain & Perennial Agriculture | The Land Institute". The Land Institute. Retrieved 2017-12-14.
- Culman, Steve W., Sieglinde S. Snapp, Mary Ollenburger, Bruno Basso, and Lee R. DeHaan. “Soil and water quality rapidly responds to the perennial grain Kernza wheatgrass.” Agronomy Journal 105, no. 3 (2013): 735-744.
- Paustian, Keith, Johannes Lehmann, Stephen Ogle, David Reay, G. Philip Robertson, and Pete Smith. “Climate-smart soils.” Nature 532, no. 7597 (2016): 49-57.
- Perennial upland rice takes root An article by Paul Cox in the New Agriculturalist