Breiten sich die C4-Pflanzen in Mitteleuropa aus?

C4 species have been spreading in Central Europe for the last two decades. At present there are 67 species to be found. 48 C4 species are growing in Germany, most of them are annuals. Their habitats are characterized by high light intensity and low competition, e. g. railway stations, maize fields or banks of large rivers. Alien C4 plants have become established as agriophytes only on the banks of some rivers like Rhine, III, Elbe or Ticino. At present there is no danger to the indigenous flora. A long-time monitoring is proposed to watch the further spreading.