The effects of plant species identity on the composition of soil communities from mesocosms containing monocultures. Boxplots represent pairwise Bray-Curtis dissimilarities in community composition between vs. within soils from the same plant species (A). Hierarchical clustering diagrams based on mean dissimilarities across the plant species (B). Bipartite network diagram, where edges (lines) connect plant species (green circles) to fungal taxa (red points) that occurred in the same mesocosm (C). The composition of cosmopolitan soil taxa (those taxa associated with all plant species), intermediate (taxa associated with only 2 to 20 plant species), and specialized (taxa that associate with only a single plant species) (D). The composition of functional groups of fungal taxa identified as being cosmopolitan, intermediate, and specialized across plant species (E).