The East-West Gateway May map of the month depicts areas of prime farmland classified by the Web Soil Survey from the USDA Natural Resources Conservation Service (NRCS). Soil surveys can be used for general farm, local, and wider area planning. Farmland classification identifies map units as prime farmland, farmland of statewide importance, farmland of local importance, or unique farmland. It identifies the location and extent of the soils that are best suited to food, fiber, forage, and oilseed crops. In general, prime farmland has an adequate and dependable water supply from precipitation or irrigation, a favorable temperature and growing season, an acceptable level of acidity or alkalinity, an acceptable content of salt or sodium, and few or no rocks. Prime farmland is designated independently of current land use, but it cannot be areas of water or urban or built-up land as defined for the National Resource Inventories.
The counties in our region with the most square miles of prime farmland are Madison (180.68), St. Clair (153.28), St. Charles (116.32), and Monroe (100.42). The counties with the fewest square miles of prime farmland are the city of St. Louis and St. Louis County (39.48), Jefferson (24.99), and Franklin (21.76). In this dataset St. Louis County and the city of St. Louis are grouped together.
The Web Soil Survey is uploaded and maintained online as the single authoritative source of soil survey information with more than 95 percent of the nation’s counties accounted for. More information on this data can be accessed with the following link: https://websoilsurvey.nrcs.usda.gov/app/