Sphagnum such gemmae. Peat moss can be distinguished from other moss species by its unique branch clusters. The plant and stem color, the shape of the branch and stem leaves, and the shape of the green cells are all characteristics used to identify peat moss to species. "Sphagnum" taxonomy has been very contentious since the early 1900s; most species require microscopic dissection to be identified. In the field, most "Sphagnum" species can be identified to one of four major sections of the genus—classification and descriptions follow Andrus 2007 (Flora North America): The reciprocal monophyly of these sections and two other minor
Aulacomnium palustre plant communities, and individual moss species often have low cover and/or frequency. Moss species with coverages of 2% to 4% can be common to dominant in boreal communities, although ribbed bog moss attains coverages as great as 40% in some boreal communities. Ribbed bog moss grows in open and forested wetland communities. In unforested northern communities, ribbed bog moss is found in sedge ("Carex" spp.) meadows, sphagnum ("Sphagnum" spp.) peatlands, heath-sedge fens, and willow ("Salix" spp.)-dominated fens. In forests, ribbed bog moss grows in the ground layer of boreal and subboreal white spruce ("Picea glauca"), black spruce ("P. mariana"), mixed