I06 NOTES ON APPLE AND POTATO DISEASES 



APPLE DISEASES 



Spraying experiments on apples during the season of 1898 

 were not made with reference to any particular disease, but 

 against any disease that might make its appearance. The trees 

 sprayed were mostly Baldwins. The diseases which developed 

 were those shown in Fig. 38, characterized by small brown 



Fig. 3S. — Brown Spot of Baldwin. 



spots on the surfjice of the fruit; in Fig. 39, characterized by 

 black or sooty diffuse blotches of no appreciable thickness, also 

 on the fruit ; and in figure on title page, characterized by small, 

 round, reddish-brown spots on the leaves. The latter disease, 

 which is caused partly at least by Phyllosticta pirini^ in some 

 cases does quite serious damage. The two other diseases seem 

 to injure the fruit chiefly by rendering it unsightly. 



The trees were sprayed three times with i to 10 Bordeaux 

 mixture once before blossoming, again just after the fall of the 

 petals, and a third time about two weeks later. Paris green 

 was added to the mixture at the second spraying for the cod- 

 ling moth. 



The followins: table shows the results : 



Nearly or quite Badly 



free from spots. Spotted. spotted. 



Brown spot on Baldwin, Unsprayed, 48 per cent. 44 per cent. 8 per cent. 



Sprayed, 78 " 18 " 4 



Sooty spot on Baldwin, Unsprayed, 17 " 63 " 20 " 



Sprayed, 83 " 14 " 3 '' 



Sooty spot on Greening, Unsprayed, 18 " 57 " 25 " 



Sprayed, 77 " y:^ " o 



