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The Twelve Orders of Soil Taxonomy

Oxisols: Soils of the Great Plaisn Slide Set, University of NebraskaIn 1975, Soil Taxonomy was published by the United States Department of Agriculture’s Soil Survey Staff. This system for classifying soils has undergone numerous changes since that time, and the 2nd edition was published in 1999. Soil Taxonomy remains one of the most widely used soil classification systems in the world.

Surface cracks in vertisols, Utah. University of Idaho photo.



At the highest level, Soil Taxonomy places soils in one of 12 categories known as orders. We have put together a collection of information and images to illustrate the distribution, properties, ecological significance, and use of these 12 soil orders.