Soil Test Information Needed
Check with the soil lab where you are considering to send your sample, and make sure that they will give you information that provides the following numbers for your sample. This is called the “CEC Test” and should use the Mehlich 3 extraction method for best results. For a list of labs that provide all or most of this kind of information, email us at

Calcium (Ca) in lbs. or ppm (multiply ppm by 2 to get lbs./Acre)
Calcium in Base Saturation %
Magnesium (Mg) in lbs. or ppm
Magnesium in Base Saturation %
Potassium (K) in lbs. or ppm (if Potash number is given, multiply by 0.83 to get Potassium)
Potassium in Base Saturation %
Sodium (Na) in lbs. or ppm
Sodium in Base Saturation %
Hydrogen (H)in Base Saturation %
Phosphorous (P) in lbs. or ppm (if Phosphate number is given, multiply by 0.44 to get Phosphorous)
Sulfur (S) in lbs. or ppm (if Sulfate number is given, multiply by 0.33 to get Sulfur)
Iron (Fe) in lbs. or ppm
Manganese (Mn) in lbs. or ppm
Copper (Cu) in lbs. or ppm
Boron (B) in lbs. or ppm
Zinc (Z) in lbs. or ppm

Some labs will give a number for Aluminum (Al) which will generally be higher when more acidity is present in the soil.
Published by Madison Educational & Research Institute, 474 Blue Hill Road, Marshall, NC  28753