18 



--1 ir-dry weights of potato vines on the 15-ton sub-plots. 



In pounds pe i acre. 



943 



1014 



853 



1021 



1959 



1931 



8112 



:>779 



The mean height of potato vines on the different sub-plots 

 wa> measured weekly at all stations, and in the next table there 

 are given the values recorded on July 20. 



Mean height of potato vines on July JO. 



At this time, it will be seen, no very marked difference [had 

 developed between die vines at the four stations, although the 

 influence of fertilization was making itself felt. There is, 

 however, so much difference in the extent of branching of the 

 vines that height alone, after branching begins, conveys no defi- 

 nite idea of the amount of vine which has developed. At 

 Janesville the vines came to completely cover the ground and 

 they did to a large extent at Lancaster; but this did not occur 

 on either of the poorer soils. 



MEAN INCREASES IX YIELDS ON 8 SOIL TYPES DUE TO 

 FERTILIZATION. 



If the yields of both corn and potatoes from the eight soil 

 types are brought together under the five fertilizations, the re- 

 sults will appear as next given : 



