180 Nebraska Agricultural Exp. Station, Research Bui. 6. 
Different relationships might be expected if the fertility should 
be increased indefinitely beyond the optimum condition. 
EFFECT OF A DIFFERENCE IN SOIL MOISTURE CONTENT UPON RELATION OF 
TRANSPIRATION TO ASH CONTENT. 
The ash content was determined for the plants in the 1913 
and 1914 soil saturation experiments. These are described fully 
with additional data in pages 127 to 142. The ash relationships 
are given separately for each year in Table 76 and are summarized 
in Table 77. These summary data are obtained by first averag- 
ing the 1914 plants with and without manure in each degree of 
soil saturation. This average for 1914 is then averaged with the 
1913 data. 
Table 77. — Summary showing relation of ash content of Rogue's 
Yellow Dent corn plants to transpiration and the moisture 
content of soil. Average for 1913 and 191 If. 1 
50 per cent 
70 per cent 
95 per cent 
relative 
relative 
relative 
saturation 
saturation 
saturation 
Dry weight per plant (grams) 
399.87 
512.50 
438.07 
Total weight of ash (grams) 
23.47 
29.81 
28.28 
Ash content (per cent) 
5.96 
5.72 
6.43 
Total water transpired per plant (kilos.) . . 
119.38 
171.70 
157.90 
Water transpired per gram dry matter 
(grams) 
319.00 
344.00 
370.00 
Water transpired per gram ash content 
(kilograms) 
5.33 
6.09 
6.03 
1 Data compiled from Table 76. 
EFFECT OF SIZE OF POTOMETER UPON RELATION OF TRANSPIRATION TO ASH 
CONTENT. 
It is apparent from the data in Table 78 that the limitation of 
the amount of soil available for the plant has a marked influence 
upon the various relationships. The variations due to size of 
potometer were somewhat irregular, but there was a rather 
definite trend from the smaller to the larger potometers. In 
those potometers receiving no manure, the transpiration per 
gram ash content was, from the smallest to the largest potometers, 
6.14, 5.70, 5.20, 5.50, 5.07, and 4.32 kilograms. Where manure 
was applied, these figures were 4.88, 6.03, 6.10, 5.43, 4.87, and 
4.40 kilograms. 
With an increase in the size of the potometers the total tran- 
spiration, the total dry matter, and the total ash content were 
