DRUPACEOUS FRUITS 28 



The drupes as the pomes, comprising highly valuable 

 individual trees, warrant protective, curative, even though 

 expensive measures. The diseases of the drupes, to some 

 extent, are identical with those of the pomes, since both 

 belong to the Rosaceae. There are, however, several im- 

 portant diseases peculiar to this group of hosts. The drupes 

 are especially sensitive to injury by fungicides, a fact which 

 complicates all questions of control of drupe diseases by 

 spraying. 



ALMOND 



The chief diseases: Yellows, Blight, Crown-gall, and 

 Shot-hole are discussed under peach. 



APRICOT 



The diseases of the apricot are essentially those of the 

 peach and will be more fully discussed under that head. 

 The most important are: Yellows, less common than on the 

 peach; Phyllosticta Shot-hole ; Brown-rot, especially destruc- 

 tive in the southwest; Fire-blight (Bacillus amylovorus), 

 rarely reported'^-; Scab, reported from California, Texas, 

 and Connecticut; Die-back (Valsa leucostoma) ; Crown-gall; 

 Black-spot {Pseudomonas prwii), less troublesome than on the 

 peach; Silver-leaf; Rust, especially injurious in the South- 

 west; Coryneum blight,^^ known in California, New York, 

 Australia, and northern Africa; Frost injury. Gummosis is 

 not a specific disease but a symptom brought about by any 

 one of various agencies; see peach. 

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