The 12 Soil Orders of the World

There are many types of soils in the world. Scientists have broken up types of soil into twelve orders. The orders range from soils formed from volcanic ash (Andisols) to soils that shrink and expand depending on the weather (Vertisols). To learn about all twelve orders, you can visit this site 12 Soil Orders.

The USDA soil taxonomy was created by the United States department of Agriculture in 1975. It defines the characteristics of the twelve soil orders and states where each type is most commonly found. The soil taxonomy has been constantly changing since then. The map below is an example of a map found in the soil taxonomy.