About Fairy-ring mushroom Edit
Wikipedia Article About Fairy-king mushroom on Wikipedia
A fairy ring or fairy circle, also known as a pixie ring, is a naturally occurring ring or arc of mushrooms. The rings may grow over ten meters in diameter and become stable over time as the fungus grows and seeks food underground. Even if no mushrooms are present, the underground presence of the fungus may sometimes be detected by observing the withering of grass directly above.
Fungi spread their spores in a circular fashion. Since multiple spores from separate fungi overlap in the inner part, fallow soil is only to be found away from the center of the "circle". This is how fairy rings "grow".
Although the edible Marasmius oreades is best known as the "fairy ring mushroom", other species of fungus, some of which are poisonous to humans, may also form arcs or rings.
In English folklore, fairy rings were said to be caused by fairies or pixies dancing in a circle, wearing down the grass beneath their feet.
In Scandinavian folklore, these circles were attributed to the elves and were called älvdanser, i.e. elf dances.