Whether cover crops are being implemented on the farm to bolster soil health, or for increased livestock forage, many questions about their impact on soil health remain for Keith Byerly, Commercial Sustainability Lead at The Mosaic Company.
“What we want to discover is: How efficient are some of these cover crops at nutrient uptake in cycling and is that a bridge that still gives ag retailers and farmers room to spread the workload out and still have the foundation they need to build their cash crop yields off of?” says Byerly.
Cover crops can help protect soil structure from inclement weather, expand soil aggregate stability, fix nitrogen into the soil, help root development, increase water filtration and much more. These sustainability benefits have caught the attention of farmers, researchers and renewable energy producers.
But how cover crops ultimately affect when nutrients are available for cash crops during the next cropping season is a big unknown. The first round of cover crop research trials is underway and has a myriad of other questions Byerly and his team are seeking the answers to.
- How do cover crops affect plant nutrient availability when fertilizer is applied in the fall versus when fertilizers are applied in the spring when those cover crops are in place?
- Does it affect it at all?
- Is there a difference in how it looks?
- Does the cash crop yield change?
- Does the nutrient concentration of the grain that we’re producing change?
“There is not a lot of existing research out there that looks at this as a comprehensive farming practice dataset, let alone look at and begin to understand if there’s a difference between things we know can increase cash crop yield — like MicroEssentials® and Aspire® fertilizers — and what that nutrient availability looks like when we put the cover crop in between that application and the cash crop,” Byerly says.
Spurring this research are the continued conversations surrounding how sustainable farming practices — like cover crops — can contribute to lowering the carbon intensity of feedstocks used for sustainable fuel production.
At the end of April 2024, the U.S. Department of the Treasury and Internal Revenue Service (IRS) released guidance on the Sustainable Aviation Fuel (SAF) Credit established by the Inflation Reduction Act (IRA). While these rules don’t apply to biofuels directly, they offer some insight of what is expected to come directly related to biofuels later in 2024.
“Adding cover crops to a sustainable management program is one of the most impactful carbon sequestering management practices we can deploy on farm ground,” Byerly says. “That’s why cover crops are drawing so much attention as we enter this new era of tax incentives, because the corn used to make ethanol, for instance, needs to reduce its carbon footprint by about 30 points to be carbon neutral. Cover crops by themselves can reduce that Carbon Intensity Value between 6 and 20 points.”
Starting in 2025, biofuel refiners of ethanol and hydrogenated vegetable oils (HVO) commonly referred to as renewable diesel, will be eligible for tax credits of up to $1.00 per gallon of biofuels refined. With 2.7 gallons of ethanol made from a bushel of corn, 1.5 gallons of HVO from a soybean bushel and 2.6 gallons of HVO from a bushel of canola, agriculture management could soon have a major impact on biofuel refiners.
“Even if 10% of the tax incentive gets passed on to the farmer for bringing in qualifying grains, it’s the biggest climate-friendly program that’s ever been launched at the farm level in the U.S.,” Byerly adds.
