Nitrogen Fertilizer Timing, Rate, and Source Effects on Corn and Wheat Production in the Red River Valley

Abstract

Experiments were conducted in 2015-2016 to determine if yield and protein concentration in corn (Zea mays L.) and hard red spring wheat (HRSW) (Triticum aestivum L.) could be enhanced through different nitrogen (N) fertilizer application timings, rates, and sources when compared to urea applied pre-plant and to quantify the dissolution rate of a controlled release fertilizer (CRF). The CRF effectively released N slowly over time. Placement depth did not impact the rate of release. Soil NH4+-N and NO3--N levels differed in diverse environments when different fertilizer sources were applied. Corn grain yield was not impacted by N application treatments in 2016, but the 100% N rate increased yield over other treatments in 2015. Nitrogen applied in October or November at the 100% rate increased HRSW yield over other treatments in 2016. Total grain protein and percent protein in the grain were not improved with N treatment over the check in 2015.