peat moss: see sphagnum.

peat, soil material consisting of partially decomposed organic matter; found in swamps and bogs in various parts of the temperate zone. It is formed by the slow decay of successive layers of aquatic and semiaquatic plants, e.g., sedges, reeds, rushes, and mosses. One of the principal types of peat is moss peat, derived primarily from sphagnum moss; it is used in agriculture as poultry and stable litters as well as a mulch, a soil conditioner, and an acidifying agent; it is also used in industry as an insulating material. Another type of peat is fuel peat, which is most widely used in regions where coal and wood are scarce, e.g., Ireland, Scandinavia, and parts of Russia. Peat is the earliest stage of transition from compressed plant growth to the formation of coal. Large deposits of peat in the United States are found in Michigan, California, and the Florida Everglades.

or sphagnum moss

Any of more than 160 species of plants that make up the bryophyte genus Sphagnum, which grow in dense clumps around ponds, in swamps and bogs, on moist, acid cliffs, and on lakeshores from tropical to subpolar regions. These pale-green to deep-red plants can hold 20 times their weight in water. As they die and are compressed, they form organic peat, which is harvested and dried as fuel, as seedbed cover, and as shipping packaging for plants and live aquatic animals. Gardeners stir peat into soil to increase soil moisture, porosity, and acidity and to reduce erosion.

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Organic fuel consisting of a light, spongy material formed in temperate, humid environments by the accumulation and partial decomposition of vegetable remains under conditions of poor drainage. Peat deposition is the first step in the formation of coal. Dried peat burns readily, with a smoky flame and a characteristic odour. It is used for domestic heating and can be used to fire boilers. It is only a minor contributor to the world energy supply, but large deposits occur in Canada, China, Indonesia, Russia, Scandinavia, and the U.S. Major users include Finland, Ireland, Russia, and Sweden.

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