Quercus petraea forests of the Pyrenees and northwestern Iberia, often with Tilia platyphyllos, Prunus avium, Quercus robur, Betula pendula, Sorbus torminalis, Castanea sativa and with Rhamnus frangula, Ilex aquifolium, Mespilus germanica, Corylus avellana, Vaccinium myrtillus, Pteridium aquilinum, Teucrium scorodonia, Melampyrum pratense, Lathyrus montanus, Luzula sylvatica, Luzula forsteri, Deschampsia flexuosa.