Mollisols
Mollisols have a distinctive dark surface (mollic epipedon) that is enriched with organic matter. The surface layer has a soft, fluffy feel. These soils formed from nutrient-rich parent materials and are commonly in grasslands. They are naturally fertile and generally hold large amounts of water. These soils are prized for agriculture. They are dominantly in the Great Plains and Western States.
Mollisols are soils common to grassland environments. In the United States most of the natural grasslands have been converted into agricultural fields for crop growth. Mollisols have a dark colored surface horizon, tend to be base rich, and are quite fertile. The dark color of the A horizon is the result of humus enrichment from the decomposition of litterfall. Mollisols found in more arid environments often exhibit calcification.