USDA Soil Taxonomy System

USDA. 1999. Soil Taxonomy. A Basic System of Soil Classification for Making and Interpreting Soil Surveys. Washington, DC US Department of Agriculture, Natural Resources Conservation Service. 

Table 3 compares the most commonly used peat classification systems based primarily on degree of decomposition. The U.S. system (Soil Taxonomy, USDA, 1975) and the Canadian system (Day, 1968) are essentially similar except for terminology and are based on the amount of unrubbed or rubbed fiber content. 

Soil Conservation Service. 1975. Soil taxonomy (a basic system of soil classification for making interpreting soil surveys). USDA Agriculture Handbook 436. Washington, D.C. 754 pp. 

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