Briefly, soil is composed of four basic components: mineral solids, water, air and organic matter (including living biota). The mineral solids are stone fragments, sand, silt, and clay. It is the proportion of the latter three that determines the soil's texture. For example, a soil that is composed of 70% silt, 20% sand and 10% clay can be classified as silt loam using the soil texture triangle (Figure 1). Soil texture contributes to the inherent soil quality, the characteristics of the soil that result from soil forming processes These characteristics are difficult to change through soil management.


Cornell Soil Health Assessment Training Manual (pdf; 7099KB)