Vienna and the Danube River are host to two ecologically important tree species of the genus Populus: the European Aspen (Populus tremula, PT) and the white poplar (Populus alba, PA). Both have extended their natural ranges to this area after the last glaciation. Lacking pollen data for poplar hampers the search for glacial refugia - whereas the latter is assumed to be found in Southeastern Europe. The objectives of this study are to find out about the post-glacial migration paths of both species by tracing their chloroplast DNA
