How many different kinds of soil are there?

One of you realized from our soil lesson that there were many different kinds of soil. We talked about the three basic particle types of soil. The biggest particles are sand, the medium-sized particles silt, and the smallest particles called clay. Particle types determine the soil's texture. Soil scientists have a classification system using a triangle graph to represent how much of the soil contains each of the three types of particles.

But this is just the beginning of how soil scientists name and classify soil types. There are actually 12 different basic kinds of soil. They are classified by many different features such as texture, kinds of rocks and minerals that the soil comes from, the pH, the environment, and the plants and animals that are present in the soil. Within these 12 basic kinds or soil orders there are many different specific types of soil that are usually named after the place where they were first discovered. These types are called series. In the area of Philipsburg, there is a lot of the soil series called "Andover" for example.

For more information on the 12 soil orders, visit the University of Idaho's Soil Website.

Soil taxonomy poster from soils.usda.gov.