When a plant arrives in a new environment, its establishment depends on much more than sunshine and rain. Beneath the surface lies a hidden environment that can make or break its chances of surviving: a vast, microscopic world of beneficial fungi. Mycorrhizal fungi in particular, connect directly to plant roots and exchange nutrients for carbon in a symbiosis that most land plants depend on to some degree.
For years, ecologists have debated how these underground partnerships shape which non-native plants manage to establish in a new range. Building on earlier work showing how these symbionts can determine the geographic limits (1, 2)) of where a plant species can and can't survive, we wondered whether the same logic might apply to plants introduced to new regions: could a plant's mycorrhizal partners help explain which non-native species successfully establish, and which don't?
The hypotheses
When non-native plants arrive in unfamiliar territory, relying on local soil fungi can be risky. If the specific fungal partners a plant needs are missing from the new soil, plants that strictly depend on mycorrhizal fungi might struggle to establish. Because of this, we hypothesized that plants capable of living independently of mycorrhizal fungi would have an advantage: specifically, we expected two strategies to benefit most: the non-mycorrhizal strategy (plants that don't engage with mycorrhizal fungi at all) and the facultative-mycorrhizal strategy (plants that are flexible to engage with mycorrhiza or not).
We also expected this advantage to depend on context rather than hold everywhere equally. Disturbances such as land-use change, fire, and logging, have a strong influence on both plant communities and the fungal communities they depend on, reducing both plant biodiversity and availability of soil fungi. Therefore, we expected non-mycorrhizal and facultative-mycorrhizal non-natives to become more common as disturbance intensity increased.
Accounting for disturbance alongside geography and environmental conditions felt like a crucial next step. Because earlier regional studies typically looked at these factors in isolation, past results often seemed conflicting, something we hoped a unified global approach could help resolve.
Building a global dataset
To answer this question properly, we needed data on an enormous scale, combining several very different types of information: which plants grow where, whether each species is native or non-native to that region, what kind of fungal partnership each species relies on, and the environmental conditions.
We built our analysis around the sPlot database (3), a compilation of vegetation surveys from over 2.5 million surveyed plots spanning every major biome on Earth. From that initial repository, we extracted 440,788 vegetation plots and cross-referenced the native or non-native status of every plant using two independent global databases (GloNAF (4) and POWO (5)). We then layered on mycorrhizal information from the FungalRoot database (6), along with two independent measures of environmental disturbance: one capturing sudden events like fires, floods, and logging (7), and another capturing sustained human pressure like urbanization and agriculture (8).
The scale of the collaboration matched the scale of the question: contributions came from over 100 researchers across dozens of countries, many of whom have spent years collecting the vegetation plot data that made this analysis possible in the first place.
Do fungal-independent plants have the edge?
When we examined plant communities around the globe, the results were far more nuanced than we expected. Our global analysis revealed that a non-native plant's mycorrhizal strategy depends heavily on its surrounding biome and local disturbance patterns:
1. The biome effect: In drylands and grasslands, non-native plants are significantly more likely to be non-mycorrhizal than native plants, allowing them to establish without depending on fungal symbionts. In temperate forests, the pattern flips: successfully established non-natives are more likely to be mycorrhizal.
2. Disturbance type matters: Acute physical disruptions like fires, logging, or land clearing disturb soil fungal hyphae, giving non-mycorrhizal non-natives a clear edge. In contrast, stable human modification like urbanization and agriculture favors mycorrhizal non-natives, likely because in these less frequently disturbed, human-modified systems fungal partners persist or are actively spread through human activities.
Tailoring conservation strategies to local context
Researchers often look for general traits that predict which non-native plants are likely to successfully establish and naturalize in a new region. Our results suggest that, at least for mycorrhizal strategy, there is no universal signal. A trait associated with successful establishment in a grassland may be irrelevant, or even reversed, in a forest.
This means that effective prevention and management strategies need to be tailored to local ecological context and the precise kind of disturbance a landscape is experiencing, rather than relying on a one-size-fits-all checklist.
Read the paper: https://www.nature.com/articles/s41559-026-03144-9
References
- Delavaux, C.S., et al.Mycorrhizal types influence island biogeography of plants. Commun Biol 4, 1128 (2021).
- https://communities.springernature.com/posts/after-the-paper-mycorrhizal-fungi-influence-global-plant-biogeography-from-a-side-project-to-half-of-my-thesis
- https://www.idiv.de/research/projects/splot/
- Davis, A. J. S., et al., (2024). Global Naturalized Alien Flora (GloNAF). Open access data to support research on understanding global plant invasions.
- (2022). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Pringle, A., Bever et al., (2009). Mycorrhizal symbioses and plant invasions. Annual Review of Ecology, Evolution, and Systematics, 40, 699–715.
- Gomes M. C., et al., (2020). FungalRoot: global online database of plant mycorrhizal associations. New Phytologist, 227(3), 955–966.
- Zhu, Z., & Woodcock, C. E. (2014). Continuous change detection and classification of land cover using all available Landsat data. Remote Sensing of Environment, 144, 152–171. 1107
- Theobald, D. et al., (2025). Global extent and change in human modification of terrestrial ecosystems from 1990 to 2022. Scientific Data , 12(1), 1–26. 1069 1070