Soil Textural Triangle

A soil texture triangle is used to classify the texture class of soil. The sides of the soil texture triangle are scaled for the percentages of sand, silt, and clay. Clay percentages are read from left to right across the triangle (dashed lines). Silt is read from the upper right to the lower left (light, dotted lines). Sand is read from the lower right towards the upper left portion of the triangle (bold, solid lines). The boundaries of the soil texture classes are highlighted in blue. The intersection of the three sizes on the triangle gives the texture class. For instance, if you have soil with 20% clay, 60% silt, and 20% sand, it falls in the "silt loam" class.