1. A highly porous, dark-colored soils developed from parent material of volcanic origin; such as, volcanic ash, tuff, and pumice.

They are found from Iceland to Indonesia, but they typically occur in wooded highland areas of the continental lands bordering the Pacific Ocean.

Andosols have high aluminum content, and their reactions with inorganic phosphate render the phosphate essentially insoluble and unavailable for intake by plants.

Although the soils have excellent water-holding and nutrient capacity (unless leached extensively), their strong reaction with phosphate makes agriculture without fertilizing doubtful.

Andosols are similar to the Andisol order of the U.S. Soil Taxonomy.

2. From the soil classification system of the Food and Agriculture Organization, FAO.
3. Etymology: from Japanese an do, "dark soil".