Effects of invasiveness of the invasive species on the differences between invasive and native species from a subsets of the species pairs in leaf-litter nitrogen loss rate (Loss-N). “All” on the right indicates that all measured species pairs were included in the analysis. Arrows upwards from “All” indicate that species pairs containing weak and moderately invasive plants were excluded gradually and randomly from the analyses; arrows downwards from “All” indicate that species pairs containing strongly and moderately invasive plants were excluded gradually. “S” indicates that only the strongly invasive plants were compared with their co-occurring natives; “SM” indicates that both strongly and moderately invasive plants were compared with their co-occurring natives; “W” indicates that only the weakly invasive plants were compared with their co-occurring natives; “WM” indicates that both weakly and moderately invasive plants were compared with their co-occurring natives; open circles indicate the differences when a random set of species pairs was excluded. The figures between brackets on the left of each panel indicate the numbers of species pairs included in the analyses.