Relation of Nona callable Water to Hygroscopic Coefficient 77 
water during the 97 days of the experiment was equivalent to not 
more than two inches of rain and was confined chiefly to that in 
the surface foot. 
The plants in all the cylinders evidently died from lack of 
sufficient soil moisture. The slow dying of many was cut short 
by a temperature of 124° F., which, altho not fatal in itself, 
caused such a rapid transpiration that water could not be ab- 
sorbed rapidly enough to meet the requirements because of the 
small amount of free water in the portions of the subsoil where 
there was an extensive development of roots. The plants were 
already dead or dying in all the cylinders except one of Red 
Fife wheat and two of Kubanka wheat. 
In their ability to exhaust the soil moisture before dying, the 
four different crop plants showed little difference, but in their 
ability to continue alive after first showing serious injury from 
drouth they showed marked differences. The interval between 
wilting and death in the case of beans amounted to only a few 
days but in that of milo and wheat it extended to many weeks. 
Where there was a well-developed root system and no remark- 
ably high temperature occurred before the death of the plants, 
the moisture content of the soil was reduced almost to the 
hygroscopic coefficient. 
Plants in the same cylinder wilted and died independently of 
one another and simultaneous wilting was not followed by simul- 
taneous death. 
Plants started in cylinders with comparatively little free 
water in the subsoil lived longer than some started in cylinders 
with a very moist subsoil. 
The plant roots did not penetrate the subsoil where this con- 
tained practically no free water and penetrated very slowly 
where the water content was only a little above the wilting co- 
efficient. While there appeared to be a close connection between 
the early development of the plants in the different cylinders and 
the quantity of roots in the subsoil, there was little connection 
between the quantity of roots and the final development of the 
plants. Where roots were uniformly distributed, there was a 
uniform loss of free water from the different levels, but where 
the development of roots was markedly lacking in uniformity 
there were distinct differences in the loss of free water. 
In one cylinder the removal of the aerial portions of the most 
of the plants, after the root system had been fully developed and 
the soil moisture so reduced that further root development could 
not take place, proved of little or no benefit to the remaining 
plants. 
Calculated to an acre basis the yield of grain was below 6 
bushels per acre except in the case of beans, where it exceeded 
