Soil Texture Classification (Which System Do I Need?)

Soil texture analysis is the measurement of the proportions of the various sizes of the soil particles. The three major groups of soil particles are sand, silt and clay. The size measured for the particles change depending upon which system is used for defining soil particle size classification. The following are the four particle size classification systems that AGVISE Laboratories use: USDA, International (ISSS), ADAS, and W. German BBA.

AGVISE Laboratories is proficient in all methods of soil texture determination. If you do not know specifically which method should be used on your soil characterization samples, the chart below may be helpful. If you are still not sure, please contact one of our professional support staff members for further clarification.

Classification System USDA International (ISSS) ADAS W. German BBA
Sand 2.0-0.05 mm 2.0-0.02 mm 2.0-0.06 mm 2.0-0.063 mm
Silt 0.05-0.002 mm 0.02-0.002 mm 0.06-0.002 mm 0.063-0.002 mm
Clay < 0.002 mm < 0.002 mm < 0.002 mm < 0.002 mm