argillic horizon A sub-surface B soil horizon that is identified by the illuvial (see illuviation) accumulation of silicate clays. The amount of clay necessary is defined in comparison with the quantity in the overlying eluvial (see eluviation) horizon, but is at least 20 per cent more. Cutans (clay skins) may be used to help identify an argillic horizon. It is at least one-tenth as thick as overlying horizons.

argillic horizon Sub-surface B soil horizon that is identified by the illuvial (see ILLUVIATION) accumulation of silicate clays. The amount of clay necessary is defined in comparison with the quantity in the overlying eluvial (see ELUVIATION) horizon, but is at least 20% more. Cutans or clay skins may be used to help identify an argillic horizon. It is at least one-tenth as thick as the overlying horizons.

argillic horizon Subsurface B soil horizon that is identified by the illuvial (see ILLUVIATION) accumulation of silicate clays. The amount of clay necessary is defined in comparison with the quantity in the overlying eluvial (see ELUVIATION) horizon, but is at least 20 per cent more. Cutans (clay skins) may be used to help identify an argillic horizon. It is at least one-tenth as thick as overlying horizons.