Oct. 29,1917 
Fungus Fairy Rings 
225 
From the results of previous investigations and from those here pre¬ 
sented it is concluded that the progress of the fairy-ring fungus through 
the soil brings about the following chemical changes. The dead organic 
‘matter of the soil is utilized as a food supply for the saprophytic fungus. 
During the process the carbohydrates are consumed or reduced and parts 
of the protein material consumed by the fungus and reduced to ammonia. 
This combines readily to produce ammoniacal salts, or is changed by 
bacterial action to nitrites which are in turn converted into nitrates- 
The chief effect, in so far as soil chemistry is concerned, is to change the 
protein portion of the organic matter of the soil into compounds of 
nitrogen which are readily available to higher plants. 1 
PHYSICAL CHANGES 
The physical differences in the soil in different portions of fairy rings 
are due to the growth of the fungus and to the effect of the amount of 
other vegetation developed on the different zones. 
Waring in 1837 (Bayliss, 1911, p. 112-116) noticed the effect of the 
mycelium on the rate of absorption of water by the soil. In Table XV 
are presented the results of moisture determinations made by Lawes, 
Gilbert, and Warington (1883). Their results indicate less soil moisture 
in the ring than either outside or inside. Measurements made by 
Molliard (1910) showed that the soil was comparatively dry in the 
zone occupied by the mycelium (Table XVI). 
Table XV .—Percentage of water in fresh soil as collected , exclusive of stones , according 
to Lawes, Gilbert , and Warington {1883, p • 216 ). 
Location. 
Surface 
soil. 
Subsoil. 
Grove Paddock fairy-ring soils, May 19, 1874: 
Within ring. 
16. 03 
12. <8 
15. 7 1 
22. 80 
19.29 
18. 50 
23- 33 
26. 34 
26. 33 
21.95 
27. 96 
15. 68 
12. 30 
16. 24 
17. 04 
13 - 13 
13 - 23 
I 5-03 
19. 21 
On ring. 
Outside ring. 
Park fairy-ring soils, Sept. 19, 1877: 
Within ring.. 
On ring (center). 
On ring (outer edge). 
Just outside ring.... 
Park fairy-ring soils, Apr. 25, 1878: 
Within the ring. 
On ring (inside). 
On ring (outside). 
19. 14 
19. 74 
Outside the ring. 
1 While the details of the process of reduction of the proteid portion of the organic matter have formed 
no part of these studies, it is interesting to call attention here to the probability that some of the inter¬ 
mediate products, such as amino acids, are utilized directly not only by the fungi but by the higher plants. 
See Schreiner and Shorey (1910), Schreiner and Skinner (1012), Schreiner and Lathrop (1912b Schreiner 
(1913), and the review of this subject, with citations of the earlier literature In Lathrop (1917). 
