A new review article published in the OA journal IMA Fungus sheds light on the phenomenon of fungal fairy rings, mysterious circular patterns of altered vegetation found in grasslands and forests.
In the review, researchers Maurizio Zotti, Giuliano Bonanomi, and Stefano Mazzoleni from the University of Naples Federico II explore the history, ecology, and impacts of these intriguing fungal formations.
Fungal fairy rings (FFRs), they explain, occur when certain fungi grow radially outward through the soil from a central point, breaking down organic matter and affecting plant growth in distinctive circular patterns. While folklore once attributed these rings to magic, scientists now understand them as a natural process driven by underground fungal activity.
In their paper, the researchers synthesise centuries of research on FFRs, from early observations in the 1800s to modern studies using cutting-edge genomic techniques. “The study of FFRs provides a valuable opportunity to delve deeper into the complex field of soil and fungal ecology, bridging multiple scientific disciplines such as mycology, microbiology, chemistry and botany,” they write.
Describing how different types of FFRs form and expand over time, the authors note that some persist for hundreds of years, reaching massive sizes: “In French grasslands, large FFRs of I. geotropa, with a diameter of 800 m, were estimated to be around 700 years old.”
The effects of FFRs vary substantially. Indeed, the study explores the various ways FFRs impact soil properties and plant communities as they spread. In some cases, the fungal activity leads to lush green rings of stimulated plant growth. In others, it causes bands of dead or stunted vegetation.
FFRs don’t just affect plants; they also influence soil microbes. The review describes how “the development of FFR mycelial mats is associated with a general simplification of the bacterial community” in some cases, while other studies have found increased microbial diversity within fairy rings.
The researcher team emphasises that there is still much to learn about the ecological roles and formation mechanisms of FFRs. Several promising areas should be explored in future research, including investigating the volatile compounds produced by fairy ring fungi and using advanced sequencing methods to unravel how FFRs regulate species coexistence in soil and plant communities.
Concluding the study the authors assert that, while improved knowledge of FFRs may have removed some of their mystical aura, “such removal of thin magic halo has certainly not reduced the wonder for the beauty of nature in its ever surprisingly dynamic pattern and intertwined complex systems.”
Read the full research paper here.
Original source
Zotti M, Bonanomi G, Mazzoleni S (2025) Fungal fairy rings: history, ecology, dynamics and engineering functions. IMA Fungus 16: e138320. https://doi.org/10.3897/imafungus.16.138320