Competitiveness of the Exotic Silphium perfoliatum against the Native Urtica dioica: A Field Experiment

Figure 4

Living aboveground dry biomass per plant of S. perfoliatum depending on treatment: control without surrounding plants (white box), surrounded by S. perfoliatum (S around, yellow box), and surrounded by U. dioica (U around, green box). n = 9 (except U around n = 8). Different letters indicate significant differences in the respective year (Tukey’s post hoc test on LMs with log-transformed living aboveground dry biomass).