Prime and unique farmlands are designations assigned by the U.S. Department of Agriculture (USDA). Prime farmland is land that has the best combination of physical and chemical characteristics for producing food, feed, forage, fiber, and oilseed crops. The land is also used as cropland, pastureland, rangeland, forest land, or other land, but cannot be used as urban built-up land or water. According to 7 CFR 657.5, unique farmland is land other than prime farmland that is used for the production of specific high value food and fiber crops. Such land has a special combination of soil quality, location, growing season, and moisture supply that is required to economically produce sustained high quality of a specific crop when treated and managed according to acceptable farming methods. Examples of such crops are citrus, tree nuts, olives, cranberries, fruit, and vegetables.
The USDA keeps account of prime farmland and unique farmland of the nation in cooperation with other interested agencies at the national, state, and local levels of government. The objective of the account is to identify the extent and location of important rural lands that help in producing food, feed, fibre, forage, and oilseed crops.