Fairy Rings

Fairy Rings are spots or circles in pastures, which are either more bare than the rest of the field, or more green and luxuriant. Frequently a bare ring appears, like a footpath, with green grass in the centre, and the circle which the ring forms, or of which it might form a part, is often some yards in diameter. Apart from supernatural hypotheses, it was sometimes imagined that they might be the effect of lightning. Dr Withering appears to have been the first, in 1796, to ascribe them to the growth of fungi; and they are now known to be due to the outwardly spreading growth of the perennial subterranean mycelium of various fungi, chiefly species of Agaricus, even the Common Mushroom (A. campestris) showing a tendency to grow in the same manner. The spot where the agaric has already grown is unfitted for its continued nourishment, and the mycelium (spawn) extends outwards to new soil, the fungus exhausting the soil to which it extends for the immediate nourishment of grass, but enriching it afterwards by the highly stimulating products of its own decay. Fairy rings of large size sometimes occupy the same situation for many years. The circle is almost always imperfect, some accidental obstacle having broken the completeness of the expanding ring of mycelium.