Fall Applied Nitrogen

As harvest progresses, many producers in Illinois will be thinking about what is next.  One popular practice continues to be fall applied nitrogen.  This is just a reminder that fall application of nitrogen should not be started until soil temperatures reach 50 degrees Fahrenheit with a fair chance that they will stay low through the winter.  Fall applied nitrogen should also be done with nitrification inhibitors.  At less than 50 degrees, you might think that the nitrogen will not break down, however keep in mind that a warm wet spring can really mess with that idea.  It should be good insurance.  Also keep in mind that the ammonia form of nitrogen is the only suitable form for fall application.  That means that Ammonium Sulfate or Anhydrous ammonia are really the only forms to consider.  Yes you can also put on DAP or MAP, and you should take credit for the nitrogen, but the amount you end up with is really not high.  Illinois Route 16 is suggested as the southern boundary for fall applied nitrogen.  I have done enough nitrogen test to tell you that I think the line should be US 36.  As soil temperatures go lower, I will be posting the 10AM temperature on Twitter.  Follow me, @daver819 or just keep an eye on the twitter feed on my blog.