Terminology in Soil Science

For soil science terms, the reader is referred to the Glossary of Soil Science Terms published by the Soil Science Society of America, Madison, Wisconsin, http //www.soils.org. In this section, few of these terms will be defined. For details on many soil science concepts, the reader is directed to Brady and Weil (2003). 

The smallest three-dimensional unit of soil that has all the primary characteristics of that soil type and can be used to characterize that soil individual. Pedons may occupy approximately 1-10 m of the landscape. 

Polypedon. A group of pedons closely associated in the field and having similar soil properties. They are used to serve as the basic classification unit or soil individual. 

Epipedon. The diagnostic horizons that occur at the soil surface. This represents the surface horizon of soil profile. 

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