• Washington State has a wide variety of soil types due to its diverse ecology and climate.washington state image by Dawngo from Fotolia.com
  
  Step from one county to another in the state of Washington, and you'll probably walk on a different type of soil. Most of the soil deposits and current soil make up in the state are due to past glacial activity or volcanic eruptions in the region.
  
  

Tokul

• West of the Cascade Mountains in and around the Puget Trough, Tokul soil is king. A rich, fertile soil, Tokul is one of the most productive soils in the world and is considered the state soil by many, including the University of Illinois. Formed from volcanic ash, most Tokul soil in the state of Washington is used for timber production and is typically considered an unstable soil for homes, since it tends to shift when wet. Washington features more than 1,000,000 acres of Tokul soil.
  
  

Loess

• Perhaps the most common soil throughout the state of Washington, Loess is typically carried to new regions by the wind. Formed during the melting of the glaciers, Loess is typically yellow or brown in color. It creates a fertile topsoil, and deposits are typically at least a few meters thick. Loess is composed mainly of quartz and very little clay, so soil particles slide easily against each other, making Loess soil types very likely to erode.
  
  

Andisol

• Many of the areas of Washington state not covered by Loess soils feature Andisol soils. Andisol soils are composed of at least 50 percent volcanic ash and are commonly found in areas with high past volcanic activity, such as around the Washington coastline and the "ring of fire." Andisol soils tend to form in areas with cool temperatures and moderate to high rainfall and can often hold a high amount of water and nutrients.