Usually lighter in colour than the topsoil, colour change often very distinct;

Zone of accumulation where the clay partials tends to accumulate.

Zone tends to be wetter and heavier in texture, denser.

Can have a good nutrient content from minerals leaching down plus the buffering effect of the clay.

Less nitrogen as there is less oxygen for the aerobic reaction of bacteria.

Can become water-logged,

iron/clay and plough pans can form in this layer `