Total Nitrogen and Timing
Mineralization was a key factor in our total nitrogen and crop rotation trial at the Lexington Research Farm. In a typical year we tend to see the maximum yield level out around 220-240 total lbs of nitrogen, but given the mineralization that occurred and the 2015 growing climate, it was reduced closer to 180 lbs. As you would expect, more nitrogen is required in corn on corn management, which is reflected in the graph below.
As we try to improve nitrogen utilization we continue to study best practices for nitrogen applications. As an industry, we need to reduce nitrogen loss in the near future to meet the Nutrient Loss Reduction Strategy. One way to accomplish that is to split applications by applying multiple times during the growing season. Again this year, fall application followed by side dress, gave the best yield by reducing nutrient loss and improving nutrient utilization.