Soil in the United States

The USDA soil taxonomy hierarchy includes orders, suborders, great groups, subgroups, families and series, with each series representing a unique kind of soil. In the United States, over 20,000 soil series have been identified.[1] Soil maps and associated data are available for more than 95 percent of the nation’s counties.[2] == Composition == The percentages of land area (in the US and associated territories, etc.) occupied by soils of the twelve orders have been estimated as: == Regional distribution of soil orders == Alfisols and Inceptisols occur widely in the US, but the circumstances of their occurrence would be difficult to characterize briefly.

Source: Wikipedia — Soil in the United States (CC BY-SA 4.0)