POTATO SPRAYING EXPERIMENTS IN 1903/ 



F. C. STEWART, H. J. EUSTACE AND F. A. SIRRINE 



SUMMARY. 



This bulletin gives the results of the second year's work on the 

 ten-year potato spraying experiments begun in 1902; also, an 

 account of six business experiments conducted by farmers. 



The results of the ten-year experiments for 1903 are as follows : 



At Geneva, the rows sprayed three times yielded at the rate of 

 262 bushels per acre; those sprayed five times, 292, and those 

 not sprayed, 174. Thus, three sprayings increased the yield 88 

 bushels per acre, and five sprayings 118 bushels. The increase in 

 5aeld on the sprayed rows was due, almost wholly, to the better 

 protection against late blight. 



On Long Island the rows sprayed three times yielded at the 

 rate of 2463/2 bushels per acre ; those sprayed five times 263, and 

 those not sprayed 207. The increased yield due to three spray- 

 ings was 39^ bushels per acre, while that due to five sprayings 

 amounted to 56 bushels per acre. The increase in yield was due, 

 chiefly, to better protection against late blight and flea-beetles. 



The farmers' business experiments were designed to determine 

 the actual profit in spraying potatoes under ordinary farm con- 

 ditions. The increase in yield was determined and an account 

 kept of all expense. Late blight being destructive, the spraying 

 proved highly profitable. On the total area of 61 1-6 acres 

 sprayed in the six experiments in different parts of the State 



*Reprint of Bulletin No. 241. 



