Fall Nitrogen: When, Where, How Much, What Kind?

 

Are you “leaking nitrogen (N)?” Mark David, a biogeochemist at the University of Illinois (U of I) says the Corn Belt is “leaking N.” For many years he has been critical of the way farmers have been applying N to corn and contends the excess winds up in the Gulf of Mexico. In his latest comments, he says “farmers are not to blame,” and says it is the efficient tile system of the Corn Belt that moves nitrates quickly into the ditches and streams. If you are finished with harvest, and will soon be applying anhydrous ammonia to 2011 corn ground, will some of your investment be lost through “leakage?”

 

If your combine is in the machine shed and you are antsy to begin fall tillage and N application that is certainly understandable, given the 2009 nightmare. Conditions have been much better this year, but just because you are ready to apply N, U of I Soil Fertility Specialist Fabian Fernandez says the soil may not be ready to receive it. In his Sept. 24 newsletter, he says, “It is no time at all yet for anyone to be in the field applying N.”

 

Fernandez knows what you suffered through last fall and counseled many farmers who needed advice on when and how to apply N in 2010, because it was not done last year. He is aware the time window is short, but he says, “Managing N well is important, because this nutrient is both one of the most expensive inputs in today's farming operations and one that poses environmental concerns.”