Highly weathered soils found primarily in tropical regions.

Contains few minerals that can be weathered.

Often rich in Fe and Al oxides.

Most of these soils have extremely low fertility:

  • resulting from very low nutrient reserves
  • high phosphorus retention by oxide minerals
  • low cation exchange capacity (CEC)

Most nutrients in Oxisol ecosystems are contained in the standing vegetation and decomposing plant material.

Despite low fertility, can become productive with inputs of lime and fertilizer.








Hawaii Oxisol


Soils formed from basic (mafic*) igneous rocks.

* mafic - a silicate mineral or rock rich in magnesium and iron.



Hawaii Oxisol


Deep well-drained soils.

Upland soils on steep slopes.



Rwanda Oxisol


An example of a humus-rich Oxisol.

Well-suited for low-input agriculture of:

  • maize
  • bananas
  • peanuts

These soils support some of the highest population densities in the world.