Cool, moist forests with a multispecific tree layer of variable dominance, most often on more or less abrupt slopes.
Mixed forests of Acer pseudoplatanus, A. platanoides, Fraxinus excelsior, Ulmus glabra, Fagus sylvatica, Carpinus betulus, Quercus robur developed on colluvial deep soils at the foot of very rainy slopes of the collinar to submontane belts of the Alps and neighbouring ranges, often with Allium ursinum, Mercurialis perennis or the ecological group of Corydalis solida in the luxuriant herb layer; more montane form of 41.42.