soil texture

Soil texture refers to the relative proportions of sand, silt, and clay particles in a soil. These particle sizes are classified by diameter: clay is less than 0.002 mm, silt is between 0.002 mm and 0.05 mm, and sand is between 0.05 mm and 2 mm.1

The texture of a soil significantly impacts its ability to hold and transport water, air, and nutrients. Sandy soils are considered coarse-textured, while clay-rich soils are fine-textured. Loam is a textural class with roughly equal proportions of sand and silt, and about one-fifth clay.1

The spaces between soil particles, called pores, vary in size. Smaller pores are found between clay particles, while larger pores exist between sand grains. Soil porosity influences how much air and water the soil can retain, and permeability describes how easily fluids can move through it. Finer textures generally lead to higher porosity but lower permeability due to smaller pore sizes.1