Plan for Fall Nitrogen Applications

nitrogen_applicationThe timing, rates and methods of nitrogen applications vary widely across the Corn Belt as weather conditions and soil types differ from field to field. Regardless of conditions or application methods, growers can take steps to get the most out of their fall-applied nitrogen.

Weigh these factors when planning fall fertilizer applications:                    

    1. Understand fertilizer types. Consider using anhydrous ammonia in the fall. Once in the soil, all nitrogen fertilizers convert to nitrate, which is the form of nitrogen that can be lost. Ammonia converts to nitrate more slowly than other forms of nitrogen, and the risk of loss is lower.1
    2. Limit acreage for application. No more than half of planned corn acres should receive nitrogen in the fall. This limits the number of acres at risk while simultaneously balancing the benefits of a fall application with economic and environmental risks.1
    3. Temperature drives timing. Fall nitrogen applications should be based on soil temperature, not calendar date. Wait to apply nitrogen until soil temperatures drop below 50 F. Nitrosomonas bacteria are active until soils reach freezing temperature; however, their activity is greatly reduced once soil temperatures drop below 50 F.2
    4. Use a nitrification inhibitor. Nitrification inhibitors, such as N-Serve® nitrogen stabilizer, slow the conversion of ammonia to nitrate and reduce the risk of nitrogen loss.1 Instinct® II nitrogen stabilizer and N-Serve protect nitrogen in the fall so it is available in the root zone when corn needs it most in spring.

For information on protecting fall-applied nitrogen, visit

1Scharf, P., and J. Lory. 2006. University of Missouri Extension. Best Management Practices for Nitrogen Fertilizer in Missouri.
2University of Illinois at Urbana-Champaign College of Agricultural, Consumer and Environmental Sciences. 2011. Understanding fall nitrogen applications.

®™DOW Diamond, Colex-D, DMA, Duramax, Durango, Enlist, Enlist Duo, Enlist E3, FulTime, Instinct, Keystone, N-Serve, Sonic, SureStart, Surpass and Surveil are trademarks of The Dow Chemical Company (“Dow”) or an affiliated company of Dow. ®Roundup Ready is a registered trademark of Monsanto Technology LLC. Always follow IRM, grain marketing and all other stewardship practices and pesticide label directions. Roundup Ready® crops contain genes that confer tolerance to glyphosate herbicides. Glyphosate herbicides will kill crops that are not tolerant to glyphosate. B.t. products may not yet be registered in all states. Check with your seed representative for the registration status in your state. FulTime NXT, Keystone LA NXT and Keystone NXT are federally Restricted Use Pesticides. Duramax, Durango DMA, FulTime NXT, Instinct II, Keystone LA NXT, Keystone NXT, Sonic, SureStart II, Surpass NXT and Surveil Co-pack are not registered for sale or use in all states. FulTime NXT, Keystone LA NXT, Keystone NXT, SureStart II and Surpass NXT are not available for sale, distribution or use in Nassau and Suffolk counties in the state of New York. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Do not fall-apply anhydrous ammonia south of Highway 16 in the state of Illinois. Enlist E3 soybeans are being jointly developed by MS Technologies and Dow AgroSciences. Regulatory approvals are pending for the Enlist herbicide solution and crops containing Enlist herbicide tolerance traits. The information presented here is not an offer for sale. Always read and follow label directions. ©2014 Dow AgroSciences LLC