| Sample site | Municipality | Elevation (msnm) | Slope (%) | Soil type |
| 1 | San Lucas | 440 | 0 - 15 | Vertisol |
| 2 | Huetamo | 433 | 0 - 15 | Vertisol |
| 3 | Nuevo Urecho | 625 | 15 - 30 | Vertisol |
| 4 | Nuevo Urecho | 514 | 0 - 15 | Vertisol |