Sphagnum

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Sphagnum (subclass Sphagnidae, class Musci) A genus of mosses which differ in several respects from other mosses; they are sometimes classified in a separate class (Sphagnopsida). The plants are characteristically branched with branches in fascicles of 2–8. The leaves are nerveless and are composed of 2 main types of cell: narrow, green, living cells and inflated, colourless, dead cells. The latter cells readily become filled with water, allowing the plant to hold many times its own weight of water. The capsules of Sphagnum are also unique; they are roughly spherical with no peristome. When the capsule is ripe, the wall shrinks on drying and the pressure inside builds up until the lid is blown off and the spores are ejected. There are many species, often difficult to distinguish, found, often abundantly, in various wet, acidic habitats: bogs, marshes, pools, moors, wet woodland, damp grassland, etc. The genus is distributed world-wide.

Sphagnum

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Sphagnum A genus of mosses, distributed worldwide, that are found, often abundantly, in wet, acidic habitats (bogs, marshes, pools, moors, wet woodland, damp grassland, etc.) There are many species, which are often difficult to distinguish. The plants are characteristically branched, with branches in fascicles of 2–8. The leaves are nerveless and composed of two main types of cell: narrow, green, living cells and inflated, colourless, dead cells. The dead cells readily fill with water, allowing the plant to hold many times its own weight of water. The capsules are roughly spherical; when ripe, the capsule wall shrinks when it dries, increasing the internal pressure until the lid is blown off, ejecting the spores.

sphagnum

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sphagnum (bot.) genus of mosses. XVIII. f. Gr. sphágnos
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sphagnum

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