Oct. 29.1917 
Fungus Fairy Rings 
1 97 
grass; and the third, a dark-green zone of grass occurred partly on the 
black zone of rotten grass, but mostly on a smaller zone which had been 
formed the year preceding. 
Practically every writer on this subject has included in his account a 
description of the rings. Few of these added materially to the de¬ 
scription given by Hutton. 
Westerhoff in 1859 (in Ritzema Bos, 1901) distinguished fairy rings 
formed by fungi and those formed by other causes. The fungus rings 
formed more or less complete circles, extending externally every year. 
They consisted cf a zone of luxuriant grass of a dark-green color, sur¬ 
rounded by a circle of mushrooms (about August) and this in turn 
surrounded by a circle of withered grass. The inside of the ring appeared 
the same as the outside. 
Jorden (1862) called attention to the green or brown rings and irregu¬ 
lar dead patches, which were known as fairy rings. 
Buckman (1870) and Kuperus (1876) described rings as formed of 
two bands, the inner one of fresh, green, luxuriant grass, and the outer 
/ 
O 
uAllnuu 
4 
lMllilikiu 
UuiiifninV/ri f f 1 
Fig. i.— A sketch of a fairy ring produced by Marasmius oreades. The center of the circle is represented 
by O. The vegetation in the central part of the circle is represented at i; the inner stimulated zone at 2, 
a bare zone at 3; and the outer stimulated zone at 4. The normal vegetation is shown at 5. The mycelium 
is represented by the dotted portion. The dotted line passing from zone 2 to 4 indicates the relative 
plant growth during the early spring when water is abundant (from Molliard, 1910). 
one of more or less brown herbage or bare soil, Buckman stated further 
that the fungi appeared in this outer ring. He also described rings 
which consisted of only the fresh green ring and often produced no fungi. 
Rings consisting of an outer dark-green zone, an intermediate yellow 
zone in which the grass was dead, and an inner green zone were de¬ 
scribed by Van Tieghem (1884, p. 1044-1045). In certain years the 
outer green band showed a large number of fungus fruits. 
Sorauer (1886, p. 270-272) stated that the rings usually consisted of 
a green ring, and that it is only during an exceptional year that fungus 
fruiting bodies occur, while Stahl (1900, p. 666-667) described a ring 
distinguished by tall and robust plants of Geranium robertianum. 
Complete rings so bare of grass as to resemble footpaths, formed by 
Lycoperdon cyclicum on a bowling green, were described by McAlpine 
(1898). 
Ballion (1906) gave detailed descriptions of rings formed by Maras¬ 
mius oreades , Tricholoma georgii , Psalliota arvensis , Lycoperdon pratense. 
These were grouped on the basis of (1) the place in the ring occupied by 
the fruiting bodies; (2) whether the vegetation was killed. 
A ring of Marasmius oreades in the month of September was described 
by Molliard (1910, p. 63, fig. 1) as follows: There were three distinct 
