Soil texture

Soil texture is the relative proportion of sand, silt, and clay particles in soil. It influences water retention, drainage, aeration, and workability.

Sand: Mineral soil particles larger than silt and clay, with diameters of 0.05 to 2 millimeters in the USDA system. Sand forms the coarsest fraction used to classify soil texture.
Soil water retention: The capacity of soil to hold water against gravity and make it available to plants. Clay-rich textures generally retain more water than sandy textures.
Soil textural class: A named soil category, such as sandy loam or clay, defined by sand, silt, and clay proportions. Classes condense texture measurements into practical descriptions used in soil surveys.
Soil structure: The arrangement of soil particles into aggregates and the pores between them. It describes organization that can change with management, not the particle-size proportions defining texture.
Silt: Mineral soil particles between 0.002 and 0.05 millimeters in diameter in the USDA system. Silt occupies the middle particle-size range in texture classification.
Hydraulic conductivity: A measure of how readily water moves through a porous material under a hydraulic gradient. Coarse textures often transmit water faster because they contain larger connected pores.
Irrigation scheduling: The planning of when and how much water to apply to crops. Texture helps estimate how quickly soil dries and how much water each irrigation can supply.
Soil organic matter: The decomposing and living organic material present in soil. Organic matter affects water and workability but is not one of the mineral texture fractions.
Clay: Mineral soil particles smaller than 0.002 millimeters in diameter in the USDA system. Clay is the finest fraction and strongly affects water retention and cohesion.
Soil porosity: The fraction of soil volume occupied by pores rather than solid particles. Texture influences pore-size distribution, although structure and compaction also matter.

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