The cracks close after rain when the clay minerals swell. During expansion of the clay minerals high pressures are developed within these soils, causing a characteristic soil structure with wedge-shaped aggregates in the surface soil and planar soil blocks in the subsoil. General environment Vertisols occur principally in the soils of hot environments with marked alternating wet and dry seasons. Vertisols are generally found on sedimentary plains, both on level land and in depressions. Smaller areas of Vertisols are found on hill slopes and piedmont plains.
Land use Main parts of the Vertisol regions are used for low intensity grazing.
Where irrigation is possible or in more humid environments arable land use is possible and shows a considerable potential for agricultural production. However, tillage operations can be performed in the dry season with heavy machinery. Mechanical tillage in the wet season causes serious soil compaction. Really wet land is impassable. Vertisols are imperfectly to poorly drained, leaching of soluble weathering products is limited, the contents of available calcium and magnesium are high and pH is above 7.