Peat is partly decayed plant matter that has collected in swamps and marshes over long periods of time. It is generally the first stage in the formation of coal. Dried peat varies from a light yellow-brown substance resembling tangled hay, to deeper layers of dark brown, compact material that looks like brown coal.
Peat forms in layers. The pale upper layers contain the remains of plants, herbs, and moss that died and rotted in the shallow, acid water. They are compressed by the weight of water and other plants to form peat. The lower layers are about 90 percent water, and look like mud.
Peat is found throughout the world. Belarus, Canada, Finland, and Russia have the largest deposits and are among the leading producers. Other important producers are Germany, Ireland, and Sweden. Florida, Michigan, and Minnesota are among the leading peat producers in the United States. Alaska has the largest deposits. Other peat bogs (marshes) in the United States include the Dismal Swamp in Virginia (see Dismal Swamp ).
Most peat is harvested by machine. The machines dig, chop, and mix the peat and form it into blocks. The blocks are then spread on the ground for drying. Some peat is still dug and stacked by hand.
Dried peat is used mainly as a fuel in places where coal and oil are scarce. In Ireland, for example, peat was long a major source of fuel to generate electricity. Peat is not used as a fuel in the United States because of the high cost of drying it. Black peat is used as a fertilizer. Fluffy brown peat is used as a packing material, and as bedding for farm animals.
