New York Agricultural Experiment Station. 127 



At Riverhead. — In the experiment at Riverhead no damage was 

 done by " bugs." They appeared in considerable numbers about 

 July 7 but were promptly poisoned. Flea-beetles were plentiful 

 about June 5 and again about August 14. On the latter date 

 they suddenly appeared in swarms. It seems probable that they 

 migrated to the experiment field from neighboring fields which 

 were killed by blight about that time. The unsprayed rows were 

 already nearly dead from blight and the flea-beetles soon finished 

 the sprayed rows which, at that time, still had about two-thirds 

 of their foliage. 



Early blight caused slight damage to the unsprayed plants, 

 but the chief enemy was late blight, Phytophthora infestans, which 

 made its first appearance in the experiment field on July 25. In 

 some neighboring fields it had been present since July 15. Dur- 

 ing the second week in August there was a general epidemic of 

 blight. In the experiment field the unsprayed rows suffered 

 much more than the sprayed although the latter became consid- 

 erably afifected by August 15. The contrast in appearance 

 between the sprayed and unsprayed rows was at no time as great 

 as in 1902 although the increase in yield due to spraying was 

 somewhat greater in 1903 than in 1902. 



The unsprayed rows died about August 16 while the sprayed rows 

 continued green several days longer, those of Series II holding out 

 until September i. 



AS SHOWN BY THE YIELD. 



At Geneva. — The potatoes were dug by hand October 22 and 22,. 

 As in 1902, the product of each row was sorted into two grades, 

 marketable and culls, and the weight of each grade taken. All 

 tubers larger than a hen's ^gg were graded as marketable. The 

 sorting was all done by the writers and as uniformly as possible. 



