Which soil particle is the smallest?

Which soil particle is the smallest?

• A. Clay
• B. Sand
• C. Silt
• D. Gravel

Answer: (A)

Soil texture is about how big the mineral particles are, and the order from smallest to largest is clay, silt, sand, then gravel. Clay particles are extremely tiny, typically less than about 0.002 millimeters in diameter, which makes them the smallest among common soil components. That minute size gives clay a very large surface area per unit mass and a tendency to cling together in flat, plate-like layers. Because of this structure, soils with more clay can hold a lot of water and nutrients, but water moves through them slowly. In contrast, silt particles are larger than clay but still quite fine, sand particles are coarser and drain quickly, and gravel is much larger and obvious to the eye. Since clay is the smallest, it is the correct answer.

Soil texture is about how big the mineral particles are, and the order from smallest to largest is clay, silt, sand, then gravel. Clay particles are extremely tiny, typically less than about 0.002 millimeters in diameter, which makes them the smallest among common soil components. That minute size gives clay a very large surface area per unit mass and a tendency to cling together in flat, plate-like layers. Because of this structure, soils with more clay can hold a lot of water and nutrients, but water moves through them slowly.

In contrast, silt particles are larger than clay but still quite fine, sand particles are coarser and drain quickly, and gravel is much larger and obvious to the eye. Since clay is the smallest, it is the correct answer.