Cool, moist forests with a multispecific tree layer of variable dominance, most often on more or less abrupt slopes.
Thermophilous forests of Tilia cordata, T. platyphyllos, Acer platanoides, Fraxinus excelsior, Ulmus glabra, Fagus sylvatica with Euonymus latifolia, Corylus avellana, restricted to the warm valleys of the Alpine system and some peripheral ranges, characterized by Asperula taurina, Cyclamen purpurascens and numerous transgressives of the Quercetalia pubescenti-petraeae. These remarkable relict forests are particularly characteristic of the föhn valleys of the Insubrian and northern Alps; they occur in similar situations in the Jura and the Hercynian ranges, north to the Harz.