B horizons: are commonly referred to as the subsoil. They are a zone of accumulation where rain water percolating through the soil has leached material from above and it has precipitated within the B horizons or the material may have weathered in place. Well drained soils typically have the brightest color development within the B horizons.
Subsurface horizon formed below an O, A and/or E horizon and above the C layer.
In well drained soils, the B horizon is typically a yellowish brown to strong brown color and is commonly referred to as the subsoil.
B - horizons have material (usually iron but also humus, clay, carbonates, etc.) which has moved into it (Illuviation) they also have structure development in some pedons.
Within New England, B horizons typically extend to a depth of 2 to 3 feet below the surface.