| <Null> |
| Not prime farmland |
| Prime farmland if drained |
| Farmland of statewide importance |
| All areas are prime farmland |
| Farmland of local importance; Farmland of unique importance; Prime farmland if drained and either protected from flooding or not frequently flooded during the growing season; Prime farmland if irrigated; Prime farmland if irrigated and drained; Prime farmland if irrigated and either protected from flooding or not frequently flooded during the growing season; Prime farmland if irrigated and reclaimed of excess salts and sodium; Prime farmland if protected from flooding or not frequently flooded during the growing season |
| <all other values> |