58 T. LytTLeton Lyon AND JAMES A. BizzELL 
not caused-a greater percolation of water. The same was true of the 
application of lime to the Dunkirk soil in tanks 1 to 12, in the earlier experi- 
ments. While this may not mean that the lime did not flocculate the 
upper layer of soil with which it was incorporated, it has some significance 
so far as drainage is concerned, since it indicates that liming a soil of this” 
kind would not result in facilitating the removal of water thru tile drains. | 
WATER UTILIZATION BY CROPS 
The water utilization by crops on this soil was large for the amount of | 
dry matter produced, both when calculated to the minimum transpiration 
ratio and by the evapo-transpiration ratio. The former was calculated by 
subtracting the drainage from the planted tanks from the drainage from 
the unplanted ones, and amounts to 451 pounds of water for every pound 
of dry matter in the crops raised during the five-years period. This 
appears in tabular form in table 8: ; 
TABLE 8. Minimum TRANSPIRATION FOR ALL Crops RAISED DURING FIVE-YEARS PERIOD 
; Average annual panel ates 
Tania Cropping percolation Sica mae | 
treatment per tank per tank 
(pounds) (pounds) 
p 
A ANG Sse yee eten ae HARE IRE ER ogee eels Unplanted. . 24621 Se ee ae 
Ie Ua Yel eee eau Ur recta ee eee Sener pure oe Cropped.... 1,871 1.31 
Minimum transpiration: mc cas ei svete eineaiie eee 5O LS ee ieee ae 
Minimum transpiration ratio. ..................0..-. gee ay beret tn aS an 5c 
Evapo-transpiration ratio 
The evapo-transpiration ratio was calculated by subtracting the average 
percolation thru the planted tanks for the five-years period from the rain- 
fall on the same area for the same period, and dividing this by the number 
of grams of dry matter per tank in the crops produced. This ratio is 
given in table 9: 
