Retisol
A typical horizon sequence according to Annex 3 of the WRB is: Retisols occur mainly in periglacial areas of the last glaciation in Europe and North America.In Europe, they are found along a belt from Belgium through northern Germany, Poland and Belarus to Russia.Most Retisols are dominated by high-activity clays and show a low base saturation.The WRB defines five Reference soil Groups with a compulsory argic horizon.The other four are differentiated according to the cation exchange capacity per kg clay at pH 7 (CEC / kg clay) in the argic horizon and according to the base saturation calculated per sum of exchangeable cations (BSeff) in the subsoil.