Sphagnum

Sphagnum is a genus of mosses commonly called peat moss due to its prevalence in peat bogs. Members of this genus can hold large quantities of water inside their cells; some species can hold up to 20 times their dry weight in water, which is why peat moss is commonly sold as a soil amendment. Peat moss can acidify its surroundings.

Individual peat moss plants consist of a wiry main axis with small clusters of soft, floppy side branches. The top of the plant has compact clusters of young branches. The side branches consist of a series of more-or-less overlapping, cup-shaped, or spear-shaped "leaves". Some species have thick, water-swollen "leaves" and a correspondingly plump appearance, while other species hold smaller amounts of water and thus have a thinner, stringier appearance.

The leaf-like structures are not true leaves, however. They contain two kinds of cells; small green living cells and large clear structural dead cells. They are spoon shaped or spear shaped and are clear, green, yellowish or reddish. Sphagnum also lacks true stems or roots. The brown, black or yellowish main axis is thin, wiry, and upright. Branched filaments, called rhizoids, develop on some species and serve to anchor plants to the substrate.

Spores are released from specialized black, shiny capsules located at the tips of thin stalks. Sphagnum also reproduces by fragmentation.

Peat moss can be distinguished from other moss species by its unique branch clusters. The plant color, the shape of the "leaves" growing around the "stems," and the shape of the green cells are characteristics used to identify peat moss to species.

Uses

Sphagnum moss is used as a soil amendment, packing material, absorbent, and fuel. Historically it has been used as bandage material because of its acidic, antibacterial quality.

Taxonomy

• Kingdom Plantae
• Division Bryophyta
• Subdivision Musci
• Class Sphagnopsida ? Peat mosses
• Subclass Sphagnidae
• Order Sphagnales
• Family Sphagnaceae