APRICOT DISEASES 159 



of their leaves. Accompanying this symptom is the production 

 of little or no fruit. (For full discussion see Plum, page 368.) 



YELLOWS 



Cause not known 



This is a specific disease, showing preference for the peach. 

 It is said to affect the apricot occasionally. (See discussion 

 under Peach, page 283.) 



FIRE-BLIGHT 

 Caused by Bacillus amylovorus (Burr.) Trev. 



The fire-blight disease of pears, apples and quinces was found 

 on the apricots in Colorado about 1902. It is of relatively little 

 importance, owing to the economic position of the apricot in 

 fruit-culture and also because this fruit is only occasionally 

 affected. Fruits and twigs, when attacked by Bacillus amylo- 

 vorus, present symptoms very similar to those developed on the 

 pomaceous fruits mentioned above. (See Pear, page 323.) 



REFERENCE 



Paddock, W. An apricot blight. Colorado Agr. Exp. Sta. Bui. 

 84 : 5-14. 1903. 



