| Test | Method |
| TOTAL EXCHANGE CAPACITY | Sum of the cations expressed in terms of milliequivalents per 100 grams |
| pH | Water pH 1:3 (PAL has 5 different pH tests) |
| ORGANIC MATTER | Walkley-Black method Dichromate- Sulfuric Acid 90 min, 90 o C, Spectrophotometer |
| NITROGEN | Estimated Nitrogen Release from Organic Matter |
| SULFATE-S | Calcium Phosphate extract, Spectrophotometer, In terms of PPM |
| PHOSPHATES | Bray P2 extract . Additional P tests available include P1, Olsen, P-retention, Total P |
| CATIONS | Ca, Mg, K, Na 1 N Ammonium Acetate buffered pH 7, atomic absorption spectrophotometer |
| BASE SATURATIONS | Calculated |
| SALT CONCENTRATIONS | 1:2 Salinity in terms of dS/m |
| CHLORIDE | Salt concentration extract titrated with mercuric chloride expressed in terms of PPM |
| BORON | Water extract, wet chemistry, spectrophotometer, expressed in terms of PPM |
| MICRO CATIONS | Fe, Mn, Cu, Zn proprietary extracts, expressed in terms of PPM |
| AVAILABLE N | KCl extract of Ammonia, Acetate extract of Nitrate, expressed in terms of PPM individually and total |
Other Sources:
- Handbook on Reference Methods for Soil Testing, the Council
on Soil Testing and Plant Analysis, University of Georgia, Athens, GA 30602Soil
- Testing and Plant Analysis Laboratory Manual, Benton Laboratories, Inc, P.O.
Box 5455, Athens, GA 30604
Note:
Besides differences in extractions, lab results vary due to different soil to
extract ratios, shaking time, and terms of expression; our models for balanced
soils are proprietary information