You can compare the economic values of different materials by dividing the retail prices by their RNV values. This shows the material with the higher retail price actually is more economical, based on its neutralizing value. Some corn growers may want to apply Grade B materials with the idea it will eventually dissolve. Research shows coarse lime particles may take from 4 to 20 or more years to dissolve in soil. Therefore, application of a low-grade, coarse material with the hope it will eventually work is poor agronomic and business management.
Corn usually requires more N than can be supplied by soil or atmospheric sources.
Nitrogen management in row crop production is under close scrutiny by many environmental stakeholders with respect to its possible movement to ground and surface waters. Nitrogen is very mobile in soils and undergoes fairly rapid transformations compared to other nutrients. In warm, humid climates such as in Mississippi, soil-based N transformations occur throughout the year. Base your decision on a nitrogen source on price, availability, ease of application, and potential for volatilization. All sources of nitrogen are equally efficient if they are properly applied in appropriate situations.