| Crop | Years grown |
|---|---|
| wheat | |
| maize | |
| soybeans |
| Variable | Material | Units | Frequency | Scale | Comment |
|---|---|---|---|---|---|
| Grain yield trait | All crops | kg/ha | annually | ||
| Soil organic matter | Soil | g/kg | annually | ||
| pH | Soil | annually | |||
| Extractable P | Soil | mg/kg | annually | Bray and Kurtz 1-P | |
| Nitrate-N | Soil | mg/kg | annually (maize and wheat) | ||
| Sulphate-S | Not specified | mg/kg | annually (maize and wheat) | ||
| Potential of N mineralization | Soil | mg/kg | before wheat drilling | 7-day anaerobic incubation test | |
| N content in grain | All crops | percent | annually | ||
| S content in grain | All crops | percent | annually | ||
| P content in grain | All crops | percent | annually | ||
| thousand grain weight | All crops | g | annually |