Table 1.2-3. Optimum levels used to interpret the Mehlich 3 soil test for agronomic crops in Pennsylvania.
| Soil test | Optimum Range | Comments |
|---|---|---|
| Phosphorus (P) | 30–50 ppm | All agronomic crops. |
| pH | 6.0–7.0 | A pH of 6.0–6.5 is considered adequate for most agronomic crops; however, 6.5–7.0 is recommended for alfalfa and barley. |
| Magnesium (Mg) | 120–180 ppm 60–120 ppm |
Grass forage crops Other agronomic crops |
| Potassium (K) | 100–150 ppm 100–200 ppm |
Grain crops Forage crops |
