What guidelines can you provide for ESN application in winter wheat in Western Canada?
We have seen excellent results with ESN application in the drill rows with winter wheat. In Western Canada, this is probably the most common use of ESN in one-pass direct-seed systems. Where the soil freezes and stays frozen through the winter, ESN release will shut down until the spring thaw. For fall application in the seed row, we recommend a high percentage of your N as ESN, typically 75 to 100% to provide for maximum seed safety.
We use a factor of 2 to 3X for ESN, meaning ESN is safe up to about 2 to 3 times the normal safe rate of urea. If using 100% ESN, you should be safe up to 3X; for a blend using ESN for 75% of the total N, we suggest dropping back to 2X the safe rate of urea to account for the effects of the soluble fertilizer used with the ESN. For many dryland systems, the safe rate of ESN will accommodate the entire N application to be applied in the seed.