The A horizon is commonly known as which soil layer?

The A horizon is commonly known as which soil layer?

• A. Subsoil
• B. Bedrock
• C. Topsoil
• D. A horizon

Answer: (C)

Understanding soil horizons and which layer sits at the surface mineral soil. The A horizon is the uppermost mineral layer, right beneath any surface litter, where minerals are mixed with decayed organic matter. This mixing gives it more nutrients and a darker color, and it’s where most plant roots are active. Because of these characteristics, the A horizon is commonly called topsoil. Below it lies the subsoil (the B horizon), and far beneath are the bedrock layers (R horizon). This is why topsoil is the familiar term for the A horizon.

Understanding soil horizons and which layer sits at the surface mineral soil. The A horizon is the uppermost mineral layer, right beneath any surface litter, where minerals are mixed with decayed organic matter. This mixing gives it more nutrients and a darker color, and it’s where most plant roots are active. Because of these characteristics, the A horizon is commonly called topsoil. Below it lies the subsoil (the B horizon), and far beneath are the bedrock layers (R horizon). This is why topsoil is the familiar term for the A horizon.