Stellario-Alnetum is an association dominated by Alnus glutinosa or Fraxinus excelsior. Its herb layer contains hygrophilous species, but unlike in other types of Alnus-Fraxinus floodplain forests mesophilous species are well represented. It occurs in narrow floodplains along small to medium-sized streams from the colline to montane belt. Soils are sandy or stony. The water table can be as deep as 1 m below the surface. In many places this community has developed on abandoned wet meadows. It is widespread in the Czech Republic, being most common in deep river valleys of the Bohemian Massif and other areas with complex topography.