Assessing microbial communities across the fine root landscape.

Root-associated microbial communities are increasingly recognized as key contributors to plant function, but we still understand little about the factors driving interactions between microbes and individual roots. To have thorough understanding of this system, we must consider the immense functional and spatial heterogeneity of roots within complex root systems. In this Viewpoint, we describe a prototype study in which we map and analyze root-associated microbial communities throughout a woody root system. Our efforts demonstrate how spatially explicit sampling yields unique insights into the relative importance of factors structuring root-associated microbial communities.