Nitrogen Product, Application Timing and Method Affect Winter Wheat Germination, Yield, and Protein.

Nitrogen (N) is the most expensive input for growing grain crops and optimal use of N fertilizer can help increase the profitability of farming systems while reducing the impact of excessive N on the environment. Three N products (urea, Super U, and ESN) were applied at 80 lb/ac in the fall or spring using three methods (broadcast, mid-row banding, and with seed) in 2010-2011 crop season. Winter wheat emergence was reduced by 50% when urea was applied with seed in the fall at 90 kg N/ha, while the urea applied by mid-row banding and ESN applied with seed did not affect the wheat emergence. Winter wheat grain yield and protein concentration were significantly affected by N product, application timing, and application method. Generally, spring application had greater yields and protein concentrations than fall application due to the shallow soil and excess rainfall in the spring of 2011. Super U did not produce greater yield than urea whether applied in the fall or spring. Super U did not result in higher protein content than urea in the spring application, but the Super U treatment produced higher protein content than the regular urea applied in the fall by broadcast or banding. ESN applied in the fall did not achieve the same yield and protein content as regular urea applied in the spring. Therefore, additional topdressing of quick release N in the spring may be needed under potentially high loss conditions experienced in this experiment. Due to the abnormal weather conditions in 2011, further studies are needed.