Soil texture is determined by the distribution of which particle sizes?

Soil texture is determined by the distribution of which particle sizes?

• A. Sand, silt, clay
• B. Gravel, sand, silt
• C. Clay, silt, loam
• D. Sand, pebbles, silt

Answer: (A)

Soil texture is defined by the relative amounts of the three mineral particle size classes: sand, silt, and clay. These three fractions cover the full range of particle sizes that influence how a soil feels and behaves—drainage, water-holding capacity, and workability—because each size contributes differently to pore space and surface area. The standard texture assessments (like feel tests or texture triangles) are built on these three fractions, not on larger pieces or other classifications. Including gravel or pebbles would shift the focus to coarse fragments, not texture, since those sizes are not part of the standard texture determination. Mixing in loam references a soil texture class that arises from certain balances of those three sizes rather than being a particle size category itself. Therefore, sand, silt, and clay accurately define soil texture.

Soil texture is defined by the relative amounts of the three mineral particle size classes: sand, silt, and clay. These three fractions cover the full range of particle sizes that influence how a soil feels and behaves—drainage, water-holding capacity, and workability—because each size contributes differently to pore space and surface area. The standard texture assessments (like feel tests or texture triangles) are built on these three fractions, not on larger pieces or other classifications.

Including gravel or pebbles would shift the focus to coarse fragments, not texture, since those sizes are not part of the standard texture determination. Mixing in loam references a soil texture class that arises from certain balances of those three sizes rather than being a particle size category itself. Therefore, sand, silt, and clay accurately define soil texture.