On January 15, 2025, the United States Department of Agriculture (USDA) published an interim rule on “technical guidelines for climate-smart crops used as feedstocks for biofuels”. An interim rule by the USDA is a rule that is published in the Federal Register and allows for immediate implementation while still accepting public comment. The interim rule establishes guidelines for quantifying, reporting and verifying the greenhouse gas (GHG) emissions associated with the production of biofuel feedstock commodity crops like corn grown in the U.S. While not mentioning the 45Z tax credit by name, the guidelines are designed to facilitate quantifying, reporting and verifying the GHG emissions for producing crops that are used as feedstocks for U.S. biofuels.
The announcement from USDA reinforces the important role climate-smart agriculture (CSA) plays in in fueling clean transportation solutions. Unlike the 40B tax credit requirements, the guidelines allow for more practices and does not require these practices to be bundled. This provides more options for farmers to implement practices that work for them and accounts for the carbon benefits of climate-smart practices that are conducive to where and how they farm.
The newly released interim rule establishes a framework to connect CSA practices to the production of feedstock crops with reductions in the carbon footprint of biofuels. The rule includes three feedstock crops: corn, soy and sorghum. It also identifies CSA practices that could reduce GHG emissions or sequester carbon, such as reduced till and no-till, cover crops and nutrient management practices, including the use of nitrification inhibitors.
The interim rule allows for adoption of CSA practices both individually or in combination. This means that participating farmers have the flexibility to adopt the CSA practices that make sense for their operation, while still being able to produce feedstocks with reduced carbon intensities under the rule.
The interim rule includes guidelines on the following:
- Biofuel feedstock crops and entities in the biofuel supply chain;
- Quantification of farm-level crop-specific carbon intensity;
- Chain of custody standards for entities in the biofuel supply chain, including traceability and recordkeeping standards;
- Auditing and verification requirements; and
- CSA practice standards for the biofuel feedstock crops included under the rule.
Along with the interim rule, USDA also published a beta version of Feedstock Carbon Intensity Calculator designed to quantify the carbon intensity of farming practices at a farm level compared to a baseline without CSA practices.
While the Iowa Corn Growers Association is pleased that USDA released the interim rule, we see areas where it can be improved and clarified. We will have that chance because USDA is requesting public comment on the interim rule to help inform future revisions or additions to the final rule. Interested parties are welcome to submit comments on any aspect of the rule. The interim rule was published on January 17. Comments from the public will be accepted during the 60-day public comment period.
Ryan Steffensen and his family farm in Guthrie County Iowa and also in Winnebago County in northern Iowa. Ryan farms with his wife Amanda, his father Neil and his brother Zach.
Family farms and legacy are important to Ryan. “My overarching farm goal is profitability and expansion. I’m also passionate about creating a farming legacy and leaving the farm to my three kids. I look to improve yields and build my soils to be able to pass on my fertile, healthy and productive land to my kids.”
The Steffensen family plants mostly a corn-soybean rotation but have some continuous corn acres too. They plant their corn at 36,500 seeds per acre and use 114-day and longer hybrids to take advantage of the full growing season. Depending on the field, Ryan does variable-seeding based on soil testing results from their grid-sampling scheme. They strip-till or no-till depending on the farm and they plan their seeding/fertilizer operations to exceed their corn yield goal of 250 bushels per acre.
Nitrogen fertilizer is one of a corn farmer’s biggest expenses. Ryan and his family fertilize to achieve a 0.8 nitrogen use efficiency ratio, meaning that it takes 0.8 pounds of nitrogen to produce a bushel of corn. In 2024, they were able to attain a 0.64 ratio which is significantly better than the state average. Ryan describes their nitrogen program this way, “We split apply our nitrogen and have found that in-season applications are needed as the crop reaches its rapid growth phase. We apply nitrogen at planting, then side dress with a stabilizer V4-5, and finish up with a foliar treatment at V6 and at tasseling. Recently, we began applying sulfur every time we fertilize with nitrogen.”
When thinking about the upcoming 2025 growing season Ryan shared, “Constant improvement is my goal every year. I want to be the most efficient with every input that I apply on the farm. We added a considerable amount of on field tile in the last five years to help mitigate soil erosion and maximize the productivity of each acre on our farms. We will continue to split apply nitrogen and try to increase the efficiency of applied nutrients through placement, timing and fertilizer enhancements.”
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