"Definition:
Mollisols - grassland soils of the steppes and prairies, known for their high net primary productivity, fertility and ability to maintain diverse flora and fauna communities. Found in the Great Plains and Western States (NRCS Map: http://soils.usda.gov/technical/classification/orders/mollisols_map.html), their formation was a result of the following factors:
1. Climate
2. Nature of parent material (e.g., bedrock)
3. Topography
4. Flora and fauna
5. Time
6. Human activities"