Evaluating Mineralizable and Applied N As a Function of Corn Yield.

Efficient nitrogen use is a fundamental management skill in corn production. While application of nitrogen through commercial fertilizers and manure plays an important role in final crop yield, the forward thinking manager must consider what nutrients come from the soil through the natural process of mineralization. Using the Illinois Soil Nitrogen Test (ISNT) and check plot yield as the basis for measuring the mineralization capability of the soil, we analyzed mineralizable N, applied N, crop yield, and growing conditions on a number of nitrogen rate studies and production fields in Illinois with the goal of determining the role of mineralization as a factor in the overall nitrogen available to the crop. Our data show the correlation between ISNT to crop yield. Based on these data a farmer can more efficiently use applied nitrogen in crop production by considering mineralizable nitrogen as a nutrient source in corn production.