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.) 
Frre-BiicHtT 
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. Bul. 
84:5-14. 1903. : 
