Forests of Fraxinus excelsior, Acer pseudoplatanus, Acer platanoides, Ulmus glabra, Tilia platyphyllos, Fagus sylvatica, on fine soil and humus-rich colluvions of ravines and cool, shady, humid slopes of the submontane level of the Black Forest, the mid-German Hercynian ranges, the Franconian and Swabian Jura, the northern and eastern pre-Alps, with Corydalis bulbosa, Corydalis intermedia, Corydalis pumila, Corydalis solida, Allium ursinum, Gagea lutea, Galanthus nivalis, Leucojum vernum, Narcissus pseudonarcissus, Scilla bifolia, Lathraea squamaria, Ranunculus ficaria.