Soil order

Histosol

Soil organic: peat or plant material accumulated where water does not allow it to decompose. More than half of the top profile is organic matter.

What it means for farming

Peatlands and wet meadows. They have no agricultural use; they have value as a reserve of water and carbon.

Histosoles on the maps

Fibrist

Histosol of slightly decomposed plant material: the fibers are recognized.

Hemist

Histosol of moderately decomposed plant material.

Saprist

Histosol of highly decomposed plant material, without recognizable fibers.

Folist

Histosol of leaf litter accumulated on rock, which is not saturated with water.

The definitions are a plain-language summary of the USDA Keys to Soil Taxonomy. The formal definition includes thickness, color and percentage thresholds that are left out here.

Sources