40 



MASS. EXPERIMENT STATION BULLETIN 209. 



plots. Roxbury Russet is larger than Baldwin on the muriate plot, and 

 the opposite is true on the sulfate plot, the differences here being quite 

 marked and increasing wdth the age of the trees. 



On the manure plot Rhode Island Greening has gained on the other 

 varieties, which may be due to the fact that it is the outside row with 

 free exposure to the north. On the ashes plot no relative change of the 

 four varieties appears. On the check plot Baldwin has gone ahead of 

 Roxbury Russet during the period of strip cultivation. Gravenstein has 

 increased its lead over the other varieties, especiallj^ during strip cultiva- 

 tion. On the sulfate plot Gravenstein has gone ahead of Baldwin during 

 the strip cultivation period, while the other varieties have maintained very 

 much the same relative positions. 



Wliile there seem to be some quite marked varietal differences in growth, 

 notably in the Baldwin and Russet on the two potash plots, it would be 

 unsafe to conclude that they are due to the fertilizer treatments. They 

 may be in part, but it is more likely that disease, natural soil differences, 

 or inherent differences in the stocks used may be responsible. 



Yield Records. 

 In Table 1 are given the total yields by plots and bj' varieties for the 

 periods when no cultivation was practiced, and for the later period of 

 strip cultivation. 



Table L — Total Yields by Varieties and by Plots (Pounds). 



1 One tree died in 1919. 

 - One tree died in 1907. 



3 One tree died in 1913. 



< One tree died before 1907, and one in 1919. 



