Remember when I said that this whole mastering Nitrogen wouldn’t be simple? That is because it is not JUST about Nitrogen. There are 16 essential nutrients in crop production, and each one of them plays a specific role in the biological processes within a plant, and when we are short any one of them it has an effect on the rest. That effect always comes back to Nitrogen, not always presenting itself as a deficiency but at the very least a lost opportunity to maximize the efficiency in which you utilized the Nitrogen you applied.
Here in lies the rub, with lower commodity prices you may be asking yourself what you should do about applications of the other nutrient this fall. I’m not going to sit here and tell you that you absolutely should or shouldn’t, rather I say we need to make sure we have done our homework before making those decisions!
The first thing to consider by far is the amount of nutrients we have removed during this year’s harvest of both corn and soybeans. In a 240-bushel corn crop, we remove 89lbs of Phosphorus, and 72lbs of Potassium, from a soil test standpoint the removal of Phosphorus is the equivalent of about 5 ppm from a soil test perspective. Soybeans that yield 70 bushels per acre will remove nearly as much Phosphorus and a considerably larger amount of Potassium. We need to be sure we are at the very minimum replacing crop removal to maximize yields and profitability at our best soil test levels. AND we need to continue to build where our soil test levels are lower.
This removal is important for us to consider as we think about the balance and completeness of our fertility plan for 2016. As we strive for better efficiency, we need to strive to make sure we are fulfilling all of the needs of our crops under all conditions. That means paying closer attention to the effect a Phosphorus deficiency will have on Nitrogen utilization because of the effect it has on root development and also how Potassium affects most all reactions within the plant, as well as Sulfur and Potassium and the formation of amino acids and proteins.
With the lower commodity prices, some may be tempted to skip a year on your fertility plan, but that is a short-term solution for a long-term problem. First you run the risk of running short on P, K, or S and then not being able to utilize the Nitrogen you have applied. Second major problem is you don’t know what the cost of future replacement of those nutrients will be; it’s better to deal with the variable that you know rather than wait to see what comes in the future. If you want to talk about how we can use all our tools and information to better manage your fertilizer investment we are ready to help you through that. All these nutrients like the decisions you make are interconnected and depend on each other, so let’s get all the information in front of us and make the best decisions for you, and the profitability of your operation.