Sphagnum short-lived, and consists almost entirely of a shiny green, spherical spore capsule that becomes black with spores. Sporophytes are raised on stalks to facilitate spore dispersal, but unlike other mosses, "Sphagnum" stalks are produced by the maternal gametophyte. Tetrahedral haploid spores are produced in the sporophyte by meiosis, which are then dispersed when the capsule explosively discharges its cap, called an operculum, and shoots the spores some distance. The spores germinate to produce minute protonemae, which start as filaments, can become thalloid, and can produce a few rhizoids. Soon afterwards, the protonema develops buds and these differentiate into its characteristic,
Sphagnum cuspidatum branch leaves can sometimes be faintly serrated. "S. cuspidatum" is a dioecious species. The spores produced are 29-38 µm, covered with large papillae on both surfaces, and appear to be covered in small blisters (pusticulate). "S. cuspidatum" can be found on wet humus under forests and on the bases of trees forming a hummock-hollow complex; in or near bogs. Distinguishing "Sphagnum cuspidatum" from "Sphagnum viride" is sometimes difficult as both occur over a similar geographic range and both grow in wet carpets. "Sphagnum cuspidatum" has narrower branch leaves and usually a distinct red tinge at the branch bases within the