The B horizon, also known as the subsoil, is a layer of soil located beneath the A horizon (topsoil) and above the C horizon (parent material). It is characterized by the accumulation of minerals and nutrients leached down from the upper layers. This horizon often has a denser texture and may contain clay, iron, and other minerals that contribute to soil fertility. The B horizon plays a crucial role in supporting plant growth by storing essential nutrients and water. It also influences the overall soil structure and drainage. Understanding the B horizon is important for agriculture, gardening, and environmental management, as it affects soil health and productivity.