| Soil texture | Clay amount g∙kg−1 | Calibration equation | r2* |
| No division | 160 - 530 |
| 0.67 |
| Fine-textured soil | 430 - 530 |
| 0.84 |
| Medium-textured soil | 160 - 350 |
| 0.70 |
| Soil texture | Clay amount g∙kg−1 | Calibration equation | r2* |
| No division | 160 - 530 |
| 0.67 |
| Fine-textured soil | 430 - 530 |
| 0.84 |
| Medium-textured soil | 160 - 350 |
| 0.70 |
