Soil physical properties—including soil texture, structure, and color—can help us understand how a given soil "acts." Soil physical properties greatly impact water infiltration, nutrient content and availability, oxygen availability, the ability of roots to penetrate soil, soil fauna, and other important aspects of soil health.
Soil Texture
As parent material weathers, it breaks down into small soil particles. We categorize these products of the weathering process into three groups according to size: sand, silt, and clay. Sand particles are the largest and clay particles are the smallest. The relative percentages of sand, silt, and clay in a soil determines the soil’s texture. Most soils are a combination of sand, silt, and clay, with one of them dominating. A silty clay loam; for example, has ~60% silt, ~30% clay, and ~10% sand; whereas a sandy clay has ~50% silt, ~40% clay, and ~70% sand.