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Notes:

This section reefers to the USDA Soil Textural Classification System, it differs from other systems such as ASSHTO, Unified, and PHI). For complete information go to:

• http://www.statlab.iastate.edu/soils/ssm/chap3av.html

• Material smaller than 2 mm diameter is called the fine earth fraction, particles larger than 2 mm are rock fragments.

• The complete break-down of fine earth fractions are:

• Very coarse sand: 2.0-1.0 mm Coarse sand: 1.0-0.5 mm Medium sand: 0.5-0.25 mmFine sand: 0.25-0.10 mm Very fine sand: 0.10-0.05 mm Silt: 0.05-0.002 mm Clay: < 0.002 mm