Underlying consolidated bedrock. Absent under many soils. Hypothetical soil profile showing the letter designation used in describing the major kinds of horizons usually present. Soil Factors Texture Soil texture refers to the relative proportion of sand, silt, and clay particles in a specific soil mass. It is easiest to determine when the soil is moist.
Sand feels gritty when rubbed by the finger.
Silt feels slick or velvety. Clay is usually sticky and plastic when wet and when pinched between the thumb and finger forms a flexible ribbon. The surface texture is normally determined from at least plow depth or 6 inches, however, erosion may have removed the surface to such an extent that only 1 or 2 inches may remain. For contests, a boxed sample of surface soil and subsoil will be provided to judge texture. In soils, several subdivisions of texture are recognized and are illustrated below.