Relative neutralizing values can be used to adjust liming recommendations from soil testing laboratories for optimum application. They also allow price comparisons between available materials. Mississippi State University Soil Testing Laboratory recommendations are based on CCE of 100 percent, and have always required adjustment based on the material to be used. Other soil testing laboratories may base lime recommendations on assumed CCE's or RNV's of less than 100 percent. Always check the recommendation basis of any particular laboratory before making lime applications.
Lime is available from many sources in Mississippi.
The RNV concept allows comparison before actual purchase. The material with the cheaper initial investment actually costs more to neutralize acidity when the properties of the lime are considered. The regulations pursuant to the Mississippi Agricultural Liming Materials Act of 1993 were amended in 1997 to define two grades of limestone-based materials. This statute also requires vendors to provide sieve analysis data and CCE of liming materials sold in the state. 50 over 30 Grade A lime meets the minimum standards in place before the regulation change.