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Are you getting all you can from your ESN program?
Every year, farmers evaluate planting options and associated cost. Nitrogen (N) is an essential input cost for which every farmer must account. Nitrogen cost can influence the fertilizer source they choose or how much to apply. With the advantages that ESN offers to farmers, it should be one of the N sources considered when evaluating their N program.
ESN is often recommended as a percentage of the total N required by the crop. For pre-plant applications, ESN is recommended at 70-90% of the total N. For post-emerge top-dress applications, 50-80% as ESN is recommended.
Some ESN users attempt to cut costs by reducing the portion of ESN in the blend and therefore do not realize ESN’s optimum performance and full benefits. Lower percentages of ESN can prevent the crop from maximizing yield and therefore reduce farmer profitability. Hundreds of studies in many environments show that best results and greatest profitability are achieved using the amount of ESN recommended for each crop and time of application. One of these studies, illustrated in the chart above, shows the yield differences from a three-year Michigan State University blend study comparing the recommended ESN blend with a low percentage ESN blend and urea.
Let’s compare grower profit between the recommended ESN percentage (75%) and the low-cost blend (25% ESN). The cost of ESN is generally about $0.18-0.20/lb of N greater than urea and about $0.15/lb of N greater than UAN (28%). The table below shows cost and profit comparisons between urea, the 75% ESN blend and the 25% ESN blend.
• The recommended blend supplying 75% of the N as ESN produced 25 bu/acre more yield than urea and 18 bu/acre more than a blend with only 25% as ESN.
• The 75% blend produced $48/acre more profit than a 25% ESN blend and $65/acre more profit than urea.
• Using less-than-recommended ESN percentages produced some benefit but failed to produce top yields and profits.
• One pre-plant ESN application (75% blend) averaged 12 bu/acre more than side-dressed urea (side-dress yields not shown).
|N Source||Increase Over Urea|
|Cost of N||Yield||Profit|
|Assumptions: N Rate = 150lbs N/acre; Corn Price = $3.50/bu; Urea Price = $276/ton ($0.30/lb N); ESN Price = $440/ton ($0.50/lb N)|