Lightly managed hay meadows and pastures on both basicline and acidocline, nutrient-rich permanently or temporarily humid soils of middle European lowlands, hills and low mountains under Atlantic or sub-Atlantic climatic conditions, from the British Isles and northwestern Iberia east to the Baltic States, the western Carpathians and Illyrian region. Among the characteristic plant components of the highly diverse communities forming this unit are Caltha palustris, Cirsium palustre, Cirsium rivulare, Cirsium oleraceum, Carduus personata, Telekia speciosa, Epilobium parviflorum, Lychnis flos-cuculi, Mentha aquatica, Scirpus sylvaticus, Stachys palustris, Bromus racemosus, Crepis paludosa, Fritillaria meleagris, Geum rivale, Polygonum bistorta, Senecio aquaticus, Trollius europaeus, Lotus uliginosus, Trifolium dubium, Equisetum palustre, Equisetum telmateia, Myosotis palustris, Deschampsia cespitosa, Angelica sylvestris, Oenanthe silaifolia, Gratiola officinalis, Inula salicina, Succisella inflexa, Dactylorhiza majalis, Ranunculus acris, Rumex acetosa, Holcus lanatus, Alopecurus pratensis, Festuca pratensis, Festuca gigantea, Juncus effusus, Juncus filiformis and Carex cespitosa.
Wet meadows and water-meadows of the lowlands of Britain, northern Germany, Poland, the Netherlands, Belgium, France and northwestern Spain, developed on nutrient-rich, acidocline alluvions of rivers and brooks with a fluctuating water regime in which Senecio aquaticus and Bromus racemosus are usually prominent, accompanied by a variable cortège; Potentilla palustris and Menyanthes trifoliata characterize mesotrophic stands, Ranunculus auricomus and Primula elatior somewhat more base-rich ones. Carex disticha is usually present and sometimes abundant, marking a transition towards Magnocaricion communities of unit D5.211. At higher altitudes, above 250 m, on base-poor soils, these communities evolve towards Polygonum bistorta-dominated communities of unit E3.415.