Insects Injurious to the. Cherry. 



197 



THE CHERRY BLACK FLY. 



(Myzus cerasi. Fab.) 



Well known to every cherry grower is the Black Fly, not only 

 in this country, but all over Europe, America, Africa, Australia (4) 

 and New Zealand. 



The black aphis of the cherry swarms over the shoots (6) and 

 gets into the leaves, causing them to curl up. So thick do they 

 become some seasons 

 that they not only 

 destroy the leaves, but 

 kill the ends of the 

 shoots. Sometimes the 

 leaves do not curl at 

 once. Fitch refers to 

 this aphis in America, 

 and records as many as 

 190 ranged down the 

 mid rib of one leaf. 



Moreover, they ex- 

 crete a large quantity of 

 very gummy honeydew, 

 and this falls on the 

 fruit and ruins it. The 

 black fungus grows 

 rapidly on the honeydew 

 of this dolphin, and this, 

 with their excrement, 

 soon ruins the crop. All 



varieties of cherries are 



attacked by it all over the kingdom. 

 and black currants. 



On the large cherry trees in Worcestershire, Mr. Ballard of 

 Eardiston informs me they do not look upon it as a serious pest, 

 yet one sees the top shoots dying from its attack. It is mainly on 

 wall fruit and on young trees that it does much damage, especially 

 to the morello cherry. 



Both sweet and sour cherries are used as the host plant. It 

 is also recorded from peaches in Australia (4) and on the plum in 

 America by Thomas (1). Ants are very abundant amongst colonies 

 of this aphis. 



FIG 153 



CHERRY BLACK APHIS (Myzus cerasi) ON CHERRY SHOOT. 



It also occurs upon red 



