The Pennine range in Northern England typically bears a vegetation dominated by Eriophorum vaginatum (on the plateaux) or of Calluna vulgaris (on more definite slopes), both on deep peat. In the Stainmore district, these are largely replaced by growing Sphagnum bogs locally known as "mosses." The detailed floristic composition of these bogs is descr.; the communities dominated by Eriophorum or Calluna may be derived from them, after the burning of the surface vegetation. Subsequent grazing tends to produce the Eriophorum community but where drainage is better and grazing less, Calluna becomes dominant. Full species lists are given for the bog types. These develop in an av. annual rainfall of ca. 140 cm., on slopes < 1 in 30. The soil pH is typically 3.8-4, but may fall to 3.45 where modification of the community and subsequent oxidation has taken place.