Soil Taxonomy and Classification - links to the USDA NRCS soils pages

• Soil Survey Division Home Page
• Keys to Soil Taxonomy
• Soil Survey Manual
• Online Soil Survey A web-based version of the soil survey including airphotos and map overlays for a large number of locations
• Soil Taxonomy  The official soil taxonomy reference manual
• Soil Taxonomy Maps  A large (15mb) file of photos and maps to accompany the Soil Taxonomy manual above.
• State Soils Photo Gallery  A series of photos, soil descriptions and maps showing the "official soils" of all the states with offically designated State Soils
• Soil Orders Gallery A description of each of the 12 orders and a photo of a "typical" example of each order - and excellent display. Also includes maps of distribution of each order
• Soils Profiles Gallery  Photos and comments on a large number of soils from different geographical areas

Other Useful places

• Automatic Textural Triangle  A page with a program that accepts the % Sand and clay, and prints back the texture of the soil. Includes a downloadable, standalone program for processing large numbers of samples.
• World Reference Base for Soil Resources   The equivalent of the US Soil Taxonomy Manual for the FAO (United Nations Food and Agriculture Organization) taxonomy
• FAOAGL - Soil Resources Mapping and Classification Portal  Soil resources: Mapping and Classification - an FAO page that includes a digital soil map (for sale) of the world.
• Soils Online Page   A page with a large variety of soils resources
• The Census of Agriculture   A page with a tremendous amount of ag data for the US - many items broken out by county