Meso-hygrophile forests of the southwestern Alps, limited to the edges of small streams in deep ravines and, sometimes, in wider valleys, dominated by Ostrya carpinifolia, with Ulmus minor, Populus alba, Salix elaeagnos, Alnus glutinosa, Fraxinus ornus, Acer campestre, Acer opalus, Quercus pubescens, Tilia cordata, Ulmus minor, Cornus sanguinea, Ligustrum vulgare, Laurus nobilis, Tamus communis, Hedera helix, Viola reichenbachiana, Euphorbia dulcis, Brachypodium sylvaticum, Melica uniflora, Carex pendula, Carex digitata and the rare Carex grioletii.