Chris Prevatt, a 32-year-old rancher based out of Alabama – and the winner of this year’s inaugural Carbon Cup – started out attending conferences. Down south for the Grassfed Exchange, up north for No-Till on the Plains. Attendees were using the same phrases at both, like “mimic nature.” Or “farm carbon.” The seed of an idea was planted in Chris’ mind.
Then, he turned to YouTube. To local farmers and ranchers already implementing practices known as “regenerative.” To nationally-recognized ones who had been at it for decades. Those who plant annual cover crops, perennials, no-till, and use adaptive grazing management. Those who armor the soil. Diversify. Keep living roots.
Chris had questions: Would the soil on his 600 pasture acres respond as well? Would these changes help make his cattle the healthiest they could possibly be? What was the right seed blend to start with? Would his wallet notice a difference?
The seed of an idea emerged as a sapling, frantic to grow. Since 2008, Chris has worked up from an annual blend of cereal rye, oats, crimson clover, and winter peas to over 30 species. He has replaced tillage with no-till, even though no-till in the South is far less common than other parts of the country. Chris, his wife, and his parents have even brought in some row crops, including corn and small grains, which are used primarily as feed for livestock. Their most recent regenerative experiment: more armor on the soil through residue management.
There’s at least one definitive answer Chris can offer. “It works,” he said.
With the Carbon Cup, Indigo sought to celebrate farmers and ranchers cultivating the nation’s healthiest soils. Through experimentation, research, and adoption of five key practices, we knew many regenerative pioneers were innovating their way into a new era for agriculture. An era more sustainable than any other the industry has seen over the last hundred years. Chris, as the national winner of the Carbon Cup, is at the forefront of that change.
In year one of the Carbon Cup, we wanted to explore the potential of agriculture soils – across both rangeland and cropland – to store carbon. Agriculture, as many are becoming increasingly aware, can change from being one of the largest contributors to climate change to instead being a massive solution. We set out to understand the upper limits of soil carbon levels, how they vary across climates and soil types, and what regenerative pioneers were doing to succeed.
Soil carbon levels were measured this year on a state-by-state basis. Chris’ land, like the other 14 state-level winners and numerous other participants, was assessed using the equivalent soil mass method, which allowed us to fairly compare competitors’ soil carbon stocks across the diverse regions, soil types, and climatic zones.
We started by pulling soil cores down to 30 centimeters. (An important note: in future competitions, we will pull cores down a full meter, since studies have shown intra-layer carbon impacts go well beyond 30 centimeters.) Using this method, we determined Chris’s competition value to be 5.4% organic carbon (~9.4% organic matter). If we translate Chris’s measured carbon percentage down to the full 30 centimeters depth sampled, his soils hold about 203 metric tons of carbon dioxide equivalents per acre. If Chris continues building his organic matter at a rate of 1% to 2% per year, this would result in 2 to 4 tons of CO2-e removed from the atmosphere per year, and earnings of $30 to $60 per acre per year through the Indigo Carbon program.
When looking at soil carbon levels across the state-level winners, different soil types, climate conditions, and planting windows impacted soil carbon levels in different regions. For those farmers further north, soil carbon levels were on the higher end of the spectrum. Down south, concentrations were generally lower. For example, Bruce Tiffany’s field in Minnesota was measured to be around 5.3% SOC, while in Georgia, Will Harris’s field contained ~1.8%. Corn Belt fields, such as the one submitted by Alyssa Ficke of Nebraska, fell in-between at ~2.4%.
Longer growing seasons in the lower latitudes provide more time for plant growth potentially increasing soil inputs, but warmer temperatures year-round also give microbes more time to break that soil carbon down and return it to the atmosphere. Regional precipitation patterns play a complicated role as well. Cash and cover crop productivity, essential to building carbon stocks, thrive under similar conditions for optimal soil organic carbon microbial decomposition.
The varying results across climates and regions demonstrate the need for more data and scientific study around the optimization of regenerative farming practices to sequester carbon and ultimately drive profitability for growers. As more data from these operations are collected, organized, and analyzed, the industry will better understand the potential of soil to hold carbon and act as a climate solution. To drive this optimization, Indigo has set out on The Terraton Experiment, a 10+ year study to understand the relationship between regenerative practices and carbon sequestration.
At the same time, Indigo is continuing to develop methods for quantifying net greenhouse gas emissions (including soil carbon stocks) on agricultural land to fuel Indigo Carbon, a program for paying farmers for increases in soil carbon levels and decreases in greenhouse gas emissions. Indigo has been collaborating with Verra and the Climate Action Reserve to develop a greenhouse gas measurement protocol for that program.
We’re just trying to do right by Alabama.
Implementing dozens of different annual and perennial covers has had a dual effect on Chris’ ranch: improving the health of both his soil and livestock.
To start with the latter, Chris said, “You can see it in the animals’ behavior, how the cattle react to new forages. There’s no comparison.” Adaptive grazing can see the cattle only “taking a bite” of some annual forages before moving on for the day, circling back after a month to graze another thirty or forty percent of the field. This technique has been shown to drive more carbon into the soil by maximizing plant growth.
As for his soil, Chris has noticed the improvement in water infiltration the most. “We got over fifteen inches of rain here in January and February,” he said. “In that case, you really need the soil to infiltrate as much water as possible. Any runoff could spell trouble for the season.” Since moving up from five- or six-way blends, the soil carbon stocks and biodiversity of the soil has improved, too.
And the secret to Chris’ success is no secret at all. “We look to bring as much diversity to nature as possible,” he said, a sentiment common amongst other farmers and ranchers using regenerative practices.
Taking a systems approach, and going back to the problem over and over and over again. We are always looking to set the best stage for nature to take care of itself.