196 
Journal of Agricultural Research 
Vol. XI, No. 5 
Table I. —List of fungi reported as causes of fairy rings and names of the investiga¬ 
tors —continued 
identified fungi —continued 
Species. 
Name used by author. 
Investigators. 
Paxillus involutus 
Tricholoma columbella 
Paxillus involutus (Batsch.) 
Fr. 
Pluteus cervinus Schaeff 
Tricholomacolumbetta Fr.... 
Tricholoma equestre L 
Tricholoma grammopodium 
Fr. 
Do. 
Tricho loma me la leuca (Pers.) 
Quel. 
Tricholoma personatum (Fr.) 
Quel. 
Do. 
Do. 
Tricho loma praemagnum . 
Tricholoma sp. 
Tricholoma terreum Schaeff.. 
Tuber sp. 
Agaricus grammopodius 
BuH. ~ * 
Agaricus (T richo loma) 
grammopodius Bull. 
Agaricus bicolor . 
Agaricus personatus . 
Agaricus ( Tricoloma ) per¬ 
sonatus Fr. 
Tricho loma praemagnum _ 
Tricholoma sp. 
Agaricus ter reus . 
Tuber sp... 
Ludwig (1906), 
Charles. 
Massart (1910). 
Charles. 
Lees (1869). 
Do. 
Shantz and Piemeisel. 
Munch (1914). 
Buckman (1870). 
Lees (1869). 
Ramaley (1916k 
Williams (1901). 
Wollaston (1807). 
Tulasne and Tulasne (1851). 
FUNGI OF DOUBTFUL IDENTITY 
Tricholoma graveolens (Pers.) 
Quel. 
Tricholoma gambosum Fr.... 
Hydnum cyaihiforme Schaeff. 
Hydnum candicans Fr. 
Caldesiellaferruginosa Sacc. . 
Agaricus graveolens .., 
....do. 
Hydnum tomentosum 
....do. 
.... do. 
Agaricus multifidus.. 
Way (1847). 
Do. 
Ludwig (1906). 
Do. 
Do. 
Jorden (1862), Ritzema Bos 
(1901). 
TYPES OF FAIRY RINGS 
The present paper is concerned only with fairy rings produced as a 
result of the growth of fleshy fungi. When the fungi are in fruit, these 
rings are easily distinguished by the more or less regular arrangement 
of the fruiting bodies (PI. 13, A). At other times the ring is easily 
distinguished by the appearance of the natural vegetation (PL 13, B). 
The differences in appearance of the vegetation in the ring as compared 
with that outside consist principally in a deeper color, due largely to 
greater chlorophyll content of the plants and in a more luxuriant 
growth, and in certain cases in a zone of bare ground or dead vegetation 
near the outer edge of the ring. 
Before taking up a detailed description of the various types of rings 
found in eastern Colorado it seems desirable to review briefly the de¬ 
scriptions already published. 
Hutton (1790) described a ring as consisting of three tracks, of which 
the first was a zone of dead or withered grass; the second lay just within 
and ran parallel to the first and appeared as a black zone of rotten 
