1. Comparison of the MRTN and Adapt-N Derived N Rates for Corn

Nitrogen application to corn is a large determinant for high yield, and rate has important implications for economic profitability and off-field movement of nitrate-N. Nitrogen rate recommendation systems have varied over time. A popular system was yield-goal based, with grain yield multiplied by a per-bushel factor and then rate adjusted for previous crop and other N inputs. Modifications of this system are still used today in some states. Seasonal (site-year) variability in economic optimum N rate...