Conclusion

In summary, we found that invasive plant species were larger and grew faster than co-occurring native plant species over time in short-term. Our results support a prediction of declining enemy release over time that the effect of soil microbes on the growth of invasive plant species changes from promotion to inhibition over time in short-term. Overall, these results suggest that regardless of the direction and strength of soil microbial feedback on invasive plant species, invasive plant species consistently may grow larger than co-occurring native plant species.