| Class | Very low | Low | Medium | High | Very high |
| Exchangeable Calcium Cmol/Kg | <0.5 | 0.5 - 2.0 | 2.0 - 4.0 | 4.0 - 6.0 | >6.0 |
| Exchangeable Calcium Cmol/Kg | <0.3 | 0.3 - 1.0 | 1.0 - 3.0 | 3.0 - 6.0 | >6.0 |