The textural triangle diagrams textural classes of soils based on their
sand, silt, and clay percentages. Locate the value of each estimated
percentage on its respective axis, and trace the lines to their intersection
within the appropriate textural class. Each class has particular
characteristics. With experience you can learn to estimate a soil
textural class based largely on its “feel” to your fingers. Textural
properties are more accurately determined when the soil is moist, rather
than wet or dry. Adapted from N.C. Brady and R.R. Weil (1999) The
Nature and Properties of Soils.