Australian acacias are one of the most notable invaders worldwide. Across Australian states, acacias became invasive or even naturalized after being introduced to ecosystems outside their natural distribution range. The relative importance of soil biota in their invasion success remains unknown, particularly that of rhizobial and fungal communities. We tested the Enemy Release Hypothesis and the Acquired Mutualism Hypothesis to disentangle the belowground invasion mechanisms that may have assisted in the invasion success of these acacias across Australia
