Gartenflüchtlinge als neue Mitglieder der Dorfflora in Nordrhein-Westfalen

A comparison of the species composition of the spontaneous flora of Northrhine-Westphalian villages in the years 1980-1984 with that of 2004/05 shows that within 20 years about 28 species have newly escaped from gardens and today are members of the spontaneous village flora of more than 1 % of the villages under investigation. Another four species formerly present in very few villages (> 1 %) are now growing spontaneously in more than 5 % of the villages. The increase in garden escapees is obviously caused by decreasing weeding intensity, urbanisation of villages as well as it might be partly a consequence of global warming. Of cause, also the time-lag well known for the naturalisation of introduced species has to be considered.