The Effects of in-Furrow Application of Urea and Urea Based Slow Release Nitrogen Products on Stand Establishment and Crop Performance of Spring Wheat.

Applying fertilizer down the tube with the seed is a time and cost-saving practice which eliminates the need for additional equipment to apply fertilizer. In the case of urea, it also mitigates losses from volatilization. The challenge is to avoid a substantial reduction in stand due to the damage that urea causes when it comes in contact with the seed. Studies have shown that ESN, a slow release nitrogen fertilizer product made of polymer coated urea granules can safely be applied with the seed at larger rates than plain urea. A trial was conducted for three years in Carrington, North Dakota. In this trial, ESN and urea were applied with the seed at different blending ratios and at different nitrogen rates. Urea treated with Agrotain Ultra (a urease inhibitor) was also used as a treatment to compare with ESN in its ability to alleviate seed damage caused by volatilization. Seed applied fertilizer treatments were compared with broadcast applications as well. Early season stand was reduced with nitrogen rates and with urea to ESN blending ratios in all three years. However the 100% ESN treated plots had no reduction in the final yield compared to broadcast application. In 2015 irrigation timing was added as a treatment to see whether seed damage could be avoided by irrigation or by planting shortly before rain is expected. Applying 0.5 inch of water soon after planting made a difference of up to 10 bushels on the treatments most exposed to urea. Yields increased with N-rates on plots where Agrotain coated urea was applied with the seed on the area that received water after planting, but decreased at the 100% optimum rate on the plots that were left dry. Protein was generally higher on the area irrigated after planting, especially at lower N-rates.