Spodosols
Spodosols typically have a dark surface layer underlain by a light eluvial horizon over a reddish, aluminum and /or iron enriched horizon (ochric, albic, and spodic diagnostic features). The soil gets its name from the bleached layer (E horizon) that looks like wood ashes or the Greek work spodos for wood ashes. The soils are acid and generally under forest. Although some are used for agriculture, this requires careful water and fertility management because they are very sandy. They are common in the northeaster U.S., the higher elevations in the Rocky Mountains, and in Florida. They require a sandy parent material and leaching, thus they need high amounts of rainfall. The diagnostic features required are the ochric and spodic horizons.
Spodsols are soils that develop under coniferous vegetation and as a result are modified by podzolization. Parent materials of these soils tend to be rich in sand. The litter of the coniferous vegetation is low in base cations and contributes to acid accumulations in the soil. In these soils, mixtures of organic matter and aluminum, with or without iron, accumulate in the B horizon. The A horizon of these soils normally has an eluvial layer that has the color of more or less quartz sand. Most spodosols have little silicate clay and only small quantities of humus in their A horizon.