Fig. 2.1.

Soil texture triangle (adapted from Soil Science, University of Sydney, 1991). This triangle is effectively equivalent to that in McDonald et al. (1994) but is easier to use because there are only two variables. This simplification is possible because clay ÷ silt + sand always add up to 100%. Example: 20% clay and 67% sand will give a loam texture.To estimate field texture grade from laboratory measurements:Step 1. Add fine and coarse sand fraction.Step 2. Construct a line at right angles to % sand line (% sand).Step 3. Construct a line at right angles to % clay line (% clay).Step 4. The point where the lines intersect gives the approximate texture group.