In the summer issue of BLUE, we introduced our readers to Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming. Edited by Paul Hawken, Drawdown lists 80 ways to reduce CO2 emissions or increase the transfer of airborne CO2 into soils and plants, a process called carbon sequestration.
Of the 80 listed practices, 16 are squarely-related to farm and ranch land conservation. These practices include afforestation, tree intercropping, managed grazing, farmland restoration and silvopasture. Silvopasture is the intentional combination of trees, forage plants and livestock together as an integrated, intensively-managed system.
In our last issue, we reprinted Drawdown’s chapter on conservation agriculture. In this issue, we’re reprinting its chapter on regenerative agriculture. Other Drawdown chapters will be reprinted in future issues.
Thank you to Paul Hawken and his associates at Project Drawdown for permission to reprint these chapters.
If you’d like to learn more about regenerative agriculture and the role it plays in carbon sequestration, here’s a recommended reading list:
The Soil Will Save Us, Kristin Ohlson
Cows Save the Planet, Judith D. Schwartz
The Grazing Revolution: A Radical Pan to Save the Earth, Allan Savory
Restoration Agriculture, Mark Shephard
Grass, Soil and Hope: A Journey through Carbon Country, Courtney White
Growing a Revolution: Bringing our Soil Back to Life, David R. Montgomery
Dirt to Soil: One Family’s Journey into Regenerative Agriculture, Gabe Brown
Reprint from Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming. Edited by Paul Hawken.
RANKING AND RESULTS BY 2050: #11
23.15 gigatons reduced CO2 | $57.2 billion net cost | $1.93 trillion net savings
Regenerative agricultural practices restore degraded land. They include no tillage, diverse cover crops, in-farm fertility (no external nutrient sources required), no pesticides or synthetic fertilizers, and multiple crop rotations, all of which can be augmented by managed grazing.
The purpose of regenerative agriculture is to continually improve and regenerate the health of the soil by restoring its carbon content, which in turn improves plant health, nutrition, and productivity.
As you will see from data at the back of this book, no other mechanism known to humankind is as effective in addressing global warming as capturing carbon dioxide from the air through photosynthesis. When converted to sugars with help from the sun, carbon produces plants and food. It feeds humankind, and, through the use of regenerative agriculture, it feeds the life of the soil. Regenerative agriculture increases organic matter, fertility, texture, water retention, and the existence of trillions of organisms that convey health and protection to the roots and plant itself. Practicing regenerative agriculture addresses all common concerns about fertility, pests, drought, weeds, and yield.
To better appreciate regenerative agriculture, it is helpful to understand what conventional agriculture is, as the dominant farming practice in the world today. It involves photosynthesis too but does not prioritize capturing soil carbon. Conventional agriculture treats the soil as a medium to which mineral fertilizers and chemicals are added. The soil is plowed, tilled, cultivated, or disked two or more times a year. Herbicides clear the weeds, insect infestation is treated with pesticides, and blight or rust is sprayed with fungicides. Lack of water is compensated for with irrigation which can cause salinization of the soils. Plowing and tilling release carbon from the soil and little or none of the carbon from the plants is sequestered.
Looking back not too many years, Americans were (and most still are) eating what author Michael Pollan calls “food-like substances,” highly processed foods with a list of mysterious ingredients longer than this paragraph. A shift started in the 1980s and ‘90s that is expanding today - the realization that human health depends on real food, not artificial, synthetic, imitation food, and that food quality goes all the way back to the land and farming practices.
ln conventional agriculture, seeds, synthetic fertilizers, and pesticides go in and food comes out; however, the soil pays a heavy price, as do water, the air, birds, beneficial insects, human health, and the climate. Just as you can manufacture fake food cheaply using fillers, fats, sugars, and starches, conventional industrial agriculture produces food cheaply by not paying the cost of the damage it causes. If you do not provide your body with true nourishment, it becomes obese, diseased, and disabled. If a farmer does not provide nourishment to the soil, it becomes infertile, diseased, and deadened. These are commonsense, simple principles that underlie regenerative practices.
One principle of regenerative agriculture is no tillage. How often do you see bare earth except on a farm, or a road cut? Soil abhors a plant vacuum. Bare land, save for deserts and sand dunes, will naturally revegetate. Plants need a home, and soil needs a cover. On farms, plows expose the soil and invert it, burying topsoil underneath. When soil is tilled and exposed to the air, the life within it decays quickly and carbon is emitted. Professor Rattan Lal estimates that at least 50% of the carbon in the earth’s soils has been released into the atmosphere over the past centuries - approximately 80 billion tons. Bringing that carbon back into the soil is a gift to the atmosphere, to be sure, but from a practical agricultural perspective, it is an invitation to farmers to move away from agrochemical farming and bring the carbon back home, where it will help them work with the land more efficiently and productively.
Increasing carbon means increasing the life of the soil. When carbon is stored in soil organic matter, microbial life proliferates, soil texture improves, roots go deeper, worms drag organic matter down their holes and make rich castings of nitrogen, nutrient uptake is enhanced, water retention increases several fold (creating drought tolerance or flood insurance), nourished plants are more pest resistant, and fertility compounds to the point where little or no fertilizers are necessary. This ability to become independent of fertilizers relies upon cover crops. Each additional percent of carbon in the soil is considered equivalent to $300 to $600 of fertilizer stored beneath.
Cover crops sown into harvested plant residues crowd out weeds and provide fertility and tilth to the subsoil. A normal cover crop might be vetch, white clover, or rye, or a combination of them at one time. Experimentation has taught regenerative farmers to plant cover crops containing 10 to 25 different varieties, each one adding a particular quality or nutrient to the soil. Gabe Brown, a renowned regenerative farmer in North Dakota, once put 70 different varieties in his seed box for pasturage. The possibilities include legumes such as spring peas, clover, vetch, cow peas, alfalfa, mung beans, lentils, fava beans, sainfoin, and sunn hemp; and brassicas such as kale, mustard, radish, turnips, and collards. Then there are broadleaves such as sunflower, sesame, and chicory; and grasses such as black oats, rye, fescue, teff, brome, and sorghum. Each plant brings distinct additions to the soil, from shading out weeds to fixing nitrogen and making phosphorus, zinc, or calcium bioavailable. When consumed by ruminants, diverse varieties of cover crops afford extraordinary nutrition. This list provides a sense of how regenerative farmers are embracing complex plant communities to grow their crops, soil, and income.
With conventional crop rotation, soy and corn might be planted in alternating years, or wheat may be planted one year and then the field is left fallow the next. That too has changed. Regenerative farms might rotate eight or nine different crops such as wheat, sunflowers, barley, oats, peas, lentils, alfalfa hay, and flax. Regenerative farmers are creating crop insurance through diversification, which prevents pockets of infestation by pests and fungi. Along with rotation, there is intercropping, in which leguminous companion crops of alfalfa or beans are grown with corn to provide fertility.
Regenerative agriculture is a practical movement, not a purist one. Some regenerative farmers are organic and others drill small amounts of synthetic fertilizer when planting com, as they make the transition to organic certification. Gabe Brown has applied no fertilizers since 2008, and no pesticides or fungicides for 15 years. He formerly used herbicides for tough invasive weeds such as Canadian thistle every two years, but has given it up because he no longer needs it.
The impact of regenerative agriculture is hard to measure and model. Individual farms cannot use a cookie-cutter approach. Rates of carbon sequestration will vary considerably in quantity and amount of time required. The results, however, are impressive. Farms are seeing soil carbon levels rise from a baseline of 1 to 2 percent up to 5 to 8 percent over ten or more years. Every percent of carbon in the soil represents 8.5 tons per acre. That growth adds up to 25 to 60 tons of carbon per acre.
There has long been a conventional wisdom that world cannot be fed without chemicals and synthetic fertilizers. However, the U.S. Department of Agriculture is now running trials on farming methodologies that eschew tillage and chemicals. Evidence points to a new wisdom: The world cannot be fed unless the soil is fed. Feeding the soil reduces carbon in the atmosphere. Soil erosion and water depletion cost $37 billion in the United States annually and $400 billion globally. Ninety-six percent of that comes from food production. India and China are losing soil thirty to forty times faster than the U.S.
Regenerative agriculture is not the absence of chemicals. It is the presence of observable science -a practice that aligns agriculture with natural principles. It restores, revitalizes, and reinstates healthy agricultural ecosystems. Indeed, regenerative agriculture is one of the greatest opportunities to simultaneously address human, soil, and climate health along with the financial well-being of farmers. It is in about biological alignment - how to live and grow better food in ways that are more productive, safer, and more resilient.
From an estimated 108 million acres of current adoption, we estimate regenerative agriculture to increase to a total of 1 billion acres by 2050. This rapid adoption is based in part on the historic growth rate of organic agriculture, as well as the projected conversion of conservation agriculture to regenerative agriculture over time. This increase could result in a total reduction of 23.2 gigatons of carbon dioxide, from both sequestration and reduced emissions. Regenerative agriculture could provide a $1.9 trillion financial return by 2050 on an investment of $57 billon.