Vertisols (from the Latin verto – turn) are clay-rich soils that contain a type of “expansive” clay that shrinks and swells dramatically. These soils therefore shrink as they dry and swell when they become wet.
When dry, vertisols form large cracks that may be more than one meter (three feet) deep and several centimeters, or inches, wide. The movement of these soils can crack building foundations and buckle roads.
Vertisols are highly fertile due to their high clay content; however, water tends to pool on their surfaces when they become wet.
Vertisols are located in areas where the underlying parent materials allow for the formation of expansive clay minerals. They occupy about 2% of the glacier-free land surface.