Chat Moss along with Risley Moss and Holcroft Moss, is also a European Union designated Special Area of Conservation, known as Manchester Mosses. The major habitats in the moss are bog, heathland, woodland and acidic grassland, subject to varying degrees of wetness depending on the local drainage. The remaining areas of bog are dominated by common cottongrass "Eriophorum angustifolium" and hare's-tail cottongrass "E. vaginatum". Bog mosses are more scarce, but "Sphagnum cuspidatum", "S. recurvum", "S. tenellum", "S. fimbriatum" and "S. subnitens" occur in patches. As the peat has become drier, areas have been taken over by purple moor grass "Molinia caerulea" and
Portlethen Moss lower elevations in every direction. Due to the high winds, moderate precipitation and cool temperatures that generally prevail, conditions are favourable for formation of an acid bog, since water stagnates, but eventually evaporates with ensuing acidity enhancement of decaying organic matter. There was virtually no drainage outlet in prehistoric times, and little drainage even in modern times. Many coastal mosses were initiated by the process of glaciation, which sheared rock formations to a generally level terrain, while also gouging moderate sized craters that would pond. This description fits the fundamental situation of Portlethen Moss, where sphagnum would have flourished over