| any of numerous mushrooms of meadows and open woods, esp. the well-known Marasmius oreades, that spread in rings originating from mycelial growth: formerly supposed to mark the paths laid by dancing fairies. |
| fairy ring n. A circle of mushrooms in a grassy area, marking the periphery of perennial underground mycelial growth. [From the belief that it is a dancing place for fairies.] |
fairy ring
a naturally occurring circular ring of mushrooms on a lawn or other location. A fairy ring starts when the mycelium (spawn) of a mushroom falls in a favourable spot and sends out a subterranean network of fine, tubular threads called hyphae. The hyphae grow out from the spore evenly in all directions, forming a circular mat of underground hyphal threads. The mushrooms that grow up from this circular underground mat form a similar pattern above ground. Gradually the underground mycelium at the centre of the circle dies out. Its living outer edges, however, keep growing year by year, and hence the diameter of the ring gradually increases. Over time the ring's underground segments die out, until the ring form on the surface can no longer be discerned.
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