Wetlands where the soil is highly organic because is it formed mostly from
incompletely decomposed plants.
This soil is called peat and its presence is what defines peatlands.
Source: Hamilton Naturalists' Club
Peat is harvested, dried, and burned as fuel in many parts of the world.
Source: Illinois Wetlands
Peatland, Adirondack Park, New York
Source: Adirondack Park