This soil has developed on mainly granitic (rock or colluvial material) in the Western Uplands. The soil is strongly acidic at the surface, becoming slightly acidic or neutral with depth.
The surface soil is usually a dark brown clayey sand to silty loam with sand and is weakly structured. It overlies a conspicuously bleached clayey sand/silty loam, sandy to sandy light clay subsurface horizon. It is massive (no structure) and contains variable amounts of coarse quartz fragments. There is a clear change to a dark yellowish brown (occasionally very pale brown) strongly medium to finely structured medium clay. Generally it has pale, orange and red mottles and contains some quartz or rock fragments and grades into lighter textured weathered material. The depth is about 120 cm or more with variable depths of the surface horizons, generally 10-20 cm for the surface and 10-40 cm for the subsurface (often deeper). Topographic position is important for depth and profile development.
Notable features include:
- Texture contrast between surface horizons and the stronger and coarser structured subsoil.
- Deeper subsoil can occasionally be sodic.
- The subsoil generally has a low to moderate nutrient status.
- These features make these soils vulnerable to erosion, particularly on sloping terrain given poor drainage characteristics and lighter surface materials.
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