USDA Soil Texturing Field Flow Chart

Preparation for Work in the Field

For assisting with soil texturing procedures and assigning a texture class using the USDA texture triangle, this chart uses step-wise procedures for estimating sand, silt, and clay content. The ribbon method is implemented to estimate the fine-grained fraction followed by placing the fraction within the texture triangle to determine Texture Class (ex: sandy loam). The accompanying guide provides instruction for determining subclass (ex: fine sandy loam) and assigning textural class modifiers for rock fragments greater than 2mm (ex: gravelly silt loam) and organic compositional textural modifiers (ex: peaty sandy clay loam). Guide is printed on durable, double-sided, plastic-coated paper.

Size: 8 ¹/₂" x 11".