Did you know that changing your nitrogen (N) management practices for various crops creates opportunities for earning carbon credit payments?  In many instances across the U.S., too much N is applied be properly utilized by the plant. Performing best practices around N management reduces N loss pathways from nitrous oxide (N₂O) emissions and groundwater leaching of nitrate (NO₃^–). The proper use of nitrogen and other replacement options of synthetic nitrogen can generate carbon credits while also reducing crop input costs.

There are a variety of nitrogen management practices to qualify for carbon credits

• Variable rate nitrogen: Traditionally, N was applied at the same rate across the entire field, meaning the whole field gets the same rate per acre. Variable rate applications match soil properties to a specific rate, which results in a variable rate across the field. Areas of the field that have a higher yield potential will receive a higher rate than those areas that have a lower yield potential. The overall result is increased efficiency and less wasted N. Since variable rate results in less N₂O, which can be converted to a CO₂ equivalent, this practice can generate carbon credits.
• Addition of nitrogen stabilizers: With the addition of nitrogen stabilizers the crop has a prolonged time to properly utilize the nitrogen source, thus possibly lessening the need for additional N to be added and reducing your overall N rate.
• Other applications of N (split application, y-drops, high-clearance equipment, aerial application, etc.): By utilizing these methods of application timing one can more accurately meet N needs of the crop and reduce the possibility of overapplication of N, which could reduce the rate of nitrogen needed and qualify for credit generation.
• Modeling/software approach – Use of Adapt-N or other nitrogen management software/programs to determine nitrogen needs based on weather and historical data improve the efficiency of N applications.

Replacement Opportunities for Nitrogen Management

• Utilizing manure for N needs: Application of manure (swine, beef, poultry, etc.) to meet the crop nutrient needs is a highly sustainable N practice. This change from a synthetic to an organic fertilizer will qualify the grower while also improving soil quality, recycle nutrients, and protect water quality if properly applied.
• Proper application of manure: Like synthetic fertilizers, there can be an over application of manure if not done properly. Be sure to utilize a Manure Management Plan (MMP) to ensure your manure is being put to proper use and not over applied. This possible lessening in total N applied could qualify a grower if the applied rate of nitrogen per acre is reduced.
• Adding a N fixing biological: Adding microbial “bugs in a jug” products that fix N via a variety of biological mechanisms can replace some of the N needs of the plant and can also generate carbon credits. Products such as Envita Nitrogen, PROVEN40, and Source are a few examples.
• Altering crop rotation: An example of this would be continuous corn to a corn/soy rotation or a corn/soy rotation to a corn/wheat/soy rotation. Since these rotations include a N fixing crop the overall N demand of the rotation is reduced and less N₂O is emitted, which means carbon credit payments can be quantified and generated.

–Written by Clay Craighton and Caleb Smith, Conservation Agronomists