Five soil forming factors act upon earth materials. These five factors acting simultaneously with different intensities result in a wide variety of soils. In the United States there are over 20,000 individual soils. There are more than a 1000 in California. Soils are named for the geographic location where they were first described. The following web site can be used to find additional information about individual soils:

http://www.statlab.iastate.edu/soils/index.html/