The USDA has finalized a rule that lets corn, soy, sorghum, and canola farmers document and verify regenerative practices to lower the carbon intensity of their crops. The rule includes a Feedstock Carbon Intensity Calculator that turns field-level data on tillage, nutrient management, and cover crops into a carbon score. That score can then be sold to biofuel producers looking for low-carbon feedstocks under the 45Z Clean Fuel Production Tax Credit. Farmers need to keep detailed records, submit data to the calculator, and pass third-party verification. The current rule uses a mass balance chain of custody, meaning the grain must be physically traced to an ethanol plant. The NCGA is pushing for a book and claim model that would let farmers sell carbon reductions separately from the grain. The Treasury and DOE still need to update their 45Z guidance to let farmers actually participate. This is a step forward for linking agricultural practices to carbon markets, but the chain of custody debate will determine how much value actually reaches growers.
