Ordination (DCA) of the resident plant community in summer 2016 and spring 2017. Cover of I. glandulifera in summer 2016 (Imp 16) and in spring 2017 (Imp 17) and important environmental variables (Suppl. material 4, Table 1) as well as volumetric soil water content (soil.water) were post-hoc fitted onto the DCA. Significant variables are shown as arrows. Plots are indicated as crosses, species as open circles. Most abundant species are labeled. Not significant environmental variables and Eigenvalues of DCA axes are given in boxes below the plots. n = 114 plots for summer, n = 111 for spring. For abbreviations of the species names see Suppl. material 5: Table S2.