With all the talk about controlling nutrient losses, both from the urban and agricultural sector, sometimes the proposed solutions seem so easy:  for agriculture, just put on all your nitrogen in the spring, preferably by side-dressing after the corn has emerged.  After all, that is when the corn is already up and ready to take in the nitrogen immediately.

Seems easy, so why don’t we all do this?  There are many factors that impact nitrogen availability, price and capability to apply in a timely manner, particularly in Illinois.  Let’s list a few:

  1.  Illinois is an anhydrous ammonia state.  Our soils can hang on to nitrogen applied in the fall, particularly if applied when soil temps fall to 50 degrees and when nitrogen stabilizers are added.   70% of all nitrogen sold in Illinois for agricultural production is in the form of anhydrous and 55% of total nitrogen applied in Illinois is in the fall.  25% is liquid nitrogen (UAN), and the remaining 5% is dry urea, applied in the spring.  Illinois has 13 ammonia terminals that are fed foremost by pipeline, then by river barges, and just one by rail.  Illinois has only one nitrogen manufacturing plant, located in East Dubuque.  In the US, 60% of all nitrogen is imported from foreign countries, adding to the logistical challenges of positioning millions of tons in a timely and cost-effective manner along with hoping that the Gulf port is not shut down by a hurricane.    
  2. Storage capacity at Illinois ammonia terminals is not such that all the ammonia needed could be provided in the spring of the year; the capacity to “turn” the terminals fast enough in the peak 2-4 week spring window doesn’t exist today.  Expanding capacity at ammonia terminals is difficult due to regulatory permitting challenges.   And putting all the ammonia down in the spring is also a challenge due to a 7-10 day waiting period after application before you can plant corn; in late spring seasons, most farmers do not like to wait to plant and will go with UAN or urea so that they can plant immediately after application.   If Illinois went to spring-only for nitrogen, the capacity to meet the demand for UAN or urea does not currently exist, and competition for these two forms of N would be severe given their popularity in all the other agricultural states and the world.  When demand is high and supplies are constrained, everyone knows what price does. 
  3. Equipment and labor are also factors.  By having a fall and spring nitrogen season, the equipment required to apply ammonia and the people needed to run the equipment are more readily available because the work load is spread out.  Again, if all the nitrogen were to be applied in a 2-3 week period in the spring, the equipment required for this feat does not currently exist, and the personnel needed to run the equipment, probably 24-7, poses serious human resource challenges for ag retailers and farmers alike.  

Illinois farmers and the ag input industry recognize the challenges facing the nutrient sector.  We are already seeing more interest by farmers to back down on fall nitrogen rates, choosing to put down a half rate and then follow in the spring with the remaining nitrogen needs for the crop.  Over time, this transition will allow the industry to respond sensibly with the infrastructure, human resources and management planning necessary to provide more flexibility with regard to meeting the nitrogen demand.   Nitrogen management will continue to evolve, but in doing so the logistics and reality of storage, terminal capacity, equipment and human resources, combined with the surprises Mother Nature always has for us, require us to be honest about the challenges and pragmatic about the future. 

Jean Payne
Illinois Fertilizer & Chemical Association

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