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Sphagnum: The Remarkable Peat Moss

Sphagnum, commonly known as peat moss, is a genus of approximately 120 species of mosses. These mosses are renowned for their exceptional water-retention capabilities and their crucial role in forming peat bogs.

Taxonomy and Nomenclature

• Scientific Name: Sphagnum Linnaeus
• Common Name: Peat Moss
• Family: Sphagnaceae (Implied, as Sphagnum is the only genus in the order Sphagnales)
• Order: Sphagnales
• Synonyms: The text mentions the Greek origin of the name "sphagnos," referring to an unknown plant, and indicates that Linnaeus established the genus in 1753.

Distribution and Habitat

• Sphagnum mosses are widely distributed and found in wet and boggy areas with acidic (low pH) soil.
• They are generally not found growing in woodlands or water containing lime.
• They are particularly prevalent in peatlands throughout the world, including the North American taiga, Scotland, and New Zealand.

Ecological Role

• Sphagnum is the most important peat-forming plant and a vital component of blanket bog ecosystems.
• Without Sphagnum mosses, bogs would not exist.
• They play a key role in carbon sequestration, absorbing and holding CO2.
• However, pollution can negatively impact Sphagnum, as seen in the Peak District where industrial and urban air pollution has decimated these mosses.

Morphological Characteristics and Growth Habits

• Sphagnum moss plants are small but grow in close proximity, forming spongy carpets and hummocks (mounds up to a meter high).
• Living and dead plants can hold large quantities of water inside their cells, ranging from 16 to 26 times their dry weight, depending on the species.
• Some species, like Sphagnum austinii, form large, hard hummocks or carpets up to 50cm in height.
• Branches of some species are described as "maggot" shaped.
• They are flowerless plants with reproductive spores that develop inside capsules.

Traditional and Modern Uses

• During World War I, Sphagnum moss was used to create millions of wound dressings due to its absorbent properties.
• It is widely used in horticulture for potting, packing plants, lining hanging baskets, and soil conditioning.
• It is considered an excellent growing medium for trees with weak roots.
• Sphagnum moss is gathered commercially for the horticultural and floristry trades.

Quirky Facts

• Sphagnum is considered the "glue" that holds the whole blanket bog community together.
• Peat moss, the dead form of Sphagnum, is the early stage of coal formation.

Specific Species Mentioned

• Sphagnum austinii
• Sphagnum cristatum (most common in Australia and used commercially)
• Sphagnum pulchrum
• Sphagnum affine
• Sphagnum antarense
• Sphagnum apiculatum
• Sphagnum auriculatum
• Sphagnum balticum

Further Information

• Scottish Natural Heritage and Forestry Commission
• IUCN UK Peatland Programme
• The Heather Trust
• Moors for the Future Partnership
• Field Studies Council
• Amgueddfa Cymru-National Museum Wales
• Canadian Sphagnum Peat Moss Association (CSPMA)