The authors mention the explosive dispersal after 1970 of Senecio inaequidens DC., an originally adventitious Southafrican plant, in the southern part of the province Limburg. It is remarkable that this species is not only naturalised now in the Netherlands, but also near-by in Belgium and W. Germany, and in N. Italy. S. inaequidens has been recorded in the Netherlands in 24 hour-squares, mainly in the province Limburg, and on 4 adventitious localities (fig. 1).