Sphagnum Sphagnum Sphagnum is a genus of approximately 380 accepted species of mosses, commonly known as "peat moss". Accumulations of "Sphagnum" can store water, since both living and dead plants can hold large quantities of water inside their cells; plants may hold 16–26 times as much water as their dry weight, depending on the species. The empty cells help retain water in drier conditions. Hence, as sphagnum moss grows, it can slowly spread into drier conditions, forming larger mires, both raised bogs and blanket bogs. These peat accumulations then provide habitat for a wide array of peatland plants, including sedges and
Sphagnum all other land plants, has an alternation of generations; like other bryophytes, the haploid gametophyte generation is dominant and persistent. Unlike other mosses, the long-lived gametophytes do not rely upon rhizoids to assist in water uptake. "Sphagnum" species can be unisexual (male or female, dioecious) or bisexual (male and female gametes produced from the same plant; monoecious); In North America, 80% of "Sphagnum" species are unisexual. Gametophytes have substantial asexual reproduction by fragmentation, producing much of the living material in sphagnum peatlands. Swimming sperm fertilize eggs contained in archegonia that remain attached to the female gametophyte. The sporophyte is relatively