In-Season Decision Support Tools for Estimating Nitrogen Side-Dress Rates for Maize in the Mid-Atlantic Coastal Plain.

Nitrogen fertilizer has been synthetically produced to nourish plants, increase yield and improve harvest quality. One of the way to increase NUE is called split application which is apply portion of N fertilizer from the beginning and apply another portion during vegetative stage. Improving accuracy of corn side dress N rate recommendations can improve profitability and reduce potential negative environmental impacts of over fertilization.  The objective of this experiment is to compare yield and NUE of side-dress rates prescribed by: 1) the Virginia Corn Algorithm; 2) the Maize-N computer simulation model; and 3) the Nutrient Expert for Maize computer simulation model to the standard rate growers would currently apply.  Four field experiments were established in 2012 and 2013 with 4 replications in a randomized complete block design. Treatments evaluated included a complete factorial of four different pre-plant rates (0, 44.8, 89.6 and 134.4 kg ha^-1) with the three different simulation model-prescribed rates and the standard rate. Expected results are using Nutrient expert has applied lesser N side-dress compare to others.