PEAT is produced by the partial decomposition of plants that accumulate,
with varying amounts of mineral matter, in old ponds, swamps, and lakes,
and in abandoned channels in valley bottoms along many rivers and
streams. Peat may be an early stage in the formation of coal.
Peat ranges from light to dark brown, the color, decomposition, and
compaction increasing with depth in the deposit. Some of the plant
remains are clearly distinguishable and appear as fibrous fragments held
together by the fine peat particles. The type of peat common in Illinois
has a high water content. Before it is dried it is soft and spongy to
the touch; upon drying, it loses much water and becomes harder.
Peat is used as a fuel in some parts of the world, but its heating value
is low compared to that of coal. It burns with a long flame and leaves a
great deal of ash because of the silt and sand that were buried with the
vegetation. Peat and peat moss are used chiefly as an absorbent, as
stable litter, as insulating and packing material, and by gardeners to
increase the water-holding capacity of soils.
Peat is found in many places in Illinois but the largest deposits are in
northeastern Illinois.