1. 
   Vertisol
   In both the FAO and USA soil taxonomy, a vertisol is a soil in which there is a high content of expansive clay known as montmorillonite that forms deep cracks in drier seasons or years. Alternate shrinking and swelling causes self-mulching, where the soil material consistently mixes itself, causing...
   Found op http://en.wikipedia.org/wiki/Vertisol
   
   
2. 
   Vertisol
   one of the 12 soil orders in the U.S. Soil Taxonomy. Vertisols are clay-rich soils that undergo significant vertical cracking during the dry seasons. ... [2 related articles]
   Found op http://www.britannica.com/eb/a-z/v/17
   
   
3. 
   Vertisol
   one of the 30 soil groups in the classification system of the Food and Agriculture Organization (FAO). Vertisols are characterized by a ...
   Found op http://www.britannica.com/eb/a-z/v/17
   
   

Tip: double click on a word to show its meaning.