Forests of Betula pubescens or B. carpatica on peaty, humid and very acid soils, colonizing bogs of reduced peat building activity and acid fens, with Molinia caerulea, Vaccinium uliginosum, V. myrtillus, Empetrum nigrum, Trientalis europaea and many sphagnums, mosses and liverworts.
Sphagnum-rich Betula pubescens or B. carpatica woods in which Molinia caerulea is accompanied by a cortège of acid fen species, in particular, Carex rostrata, C. nigra, C. echinata, Juncus acutiflorus, Agrostis canina, Narthecium ossifragum, Calamagrostis canescens.