Inceptisols, Entisols, Vertisols and Mollisols are orders of Soil. Soil Taxonomy places soils into one of 12 categories known as 'orders.' Each of these orders represents a grouping of soils with distinct characteristics and ecological significance.The 12 soil orders are Entisols, Inceptisols, Andisols, Mollisols, Alfisols, Spodosols, Ultisols, Oxisols, Gelisols, Histosols, Aridisols and Vertisols.