Idaho has a diverse landscape in which there are a variety of different soils. Soil type is determined by a number of factors. Idaho has a variety of material available to create soil types, ranging from rock to volcanic ash. In addition, precipitation and climate play a role in the formation of soil types. Idaho's precipitation ranges from 8 to 60 inches a year in various parts of the state. These differences result in different pH levels, mineral content and organisms living in the soil.
Aridisol is a dry soil type that contains calcium carbonate or limestone. This soil is not conducive to agriculture. Clay, salt and other minerals have often accumulated in the subsurface layers of this type of soil, which is found mainly in the southern parts of Idaho.
Andisols are a type of soil found mainly in northern Idaho. This type of soil contains volcanic ash and large amounts of glass. The high glass content gives the soil andic properties, meaning the soil is uniquely capable of holding moisture and makes phosphorus unavailable to plants. Phosphorus is important for cell growth.
There are small amounts of vertisols in Idaho. This type of soil has a very high clay content. It's not good as a base for architecture because it expands when wet and contracts when dry, causing problems for building foundations.
Mollisol, a soil type common in Idaho, is the type of soil in grasslands. This fertile soil is excellent for agriculture and plant growth and is rich in organic materials, which mainly come from the roots of the plants.
Alfisols are found mainly in the forests of Idaho. Alfisol is a fertile soil type for both agriculture and natural plant growth. This soil is not dry but is present in semi-humid to humid regions. Subsurface parts of this soil contain clay.
Inceptisols are common in Idaho. This type of soil is typically found in Idaho's mountain areas and in fairly humid areas. It may be used for agricultural purposes.
Entisol is also a common soil type in Idaho, found in rocky mountain areas and river beds. Entisol is a diverse type of soil that does not fit into any other category. It is used for both natural plant growth and agriculture.