Risley Moss peat accumulation filled the depression, allowing colonisation by bog mosses such as the "Sphagnum" varieties, thus giving rise to the name "moss". Risley Moss is one of only two mosses in Cheshire where the water level has been deliberately raised in an attempt to encourage the regeneration of an active bog surface. The long-term restoration project to re-wet the moss began in 1978 and was completed in 2002. This scheme was undertaken to create a series of scrapes and bunds to retain water and recreate the perfect conditions for bog flora such as cotton grass and sphagnum mosses to re-colonise
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