PEACH DISEASES 293 



Peach-rosette differs from yellows in the more tufted char- 

 acter of the growths; in the absence of premature ripening 

 of the fruit ; more rapid destruction ; and usually rosette is 

 confined to the tips of branches, occurring but rarely on trunks 

 and at the base of main limbs. It resembles yellows in the 

 pushing out of dormant (adventitious) buds which develop 

 diseased branches; the dormant buds tend to unfold in the 

 summer and autumn ; and only a portion of a tree may be 

 affected, whereas the remainder is normal. 



Cause. 



This disease does not seem to be due to plant or animal par- 

 asites, nor to any chemical ferment. On the other hand, there 

 is the slight possibility that it is caused by a bacterium which 

 as yet has not been seen. The disease is contagious; the 

 causal factor, whatever it may be, is readily spread by bud-inoc- 

 ulation, by root-grafting, or by blowing leaves. There are 

 doubtless other ways by which it is spread, but as yet they have 

 not come to light. Within two to ten months after a tree is 

 inoculated first signs of the rosette disease are apparent. 



Control. 



The prevention of rosette is not known to be possible. All 

 affected trees should be promptly destroyed. This should be 

 done early in the spring as soon as the disease appears, and 

 before the leaves fall. In those regions where the disease is 

 present, attention should be given to the plum, which at times 

 shows symptoms of rosette similar to those described for the 



peach. 



REFERENCES 



Smith, E. F. Additional evidence on the communicability of peach 



yellows and peach rosette. Part II. Peach rosette. U. S. 



Agr. Dept. Veg. Path. Div. Bui. 1 : 45-58. 1891. 

 Smith, E. F. Peach yellows and peach rosette. U. S. Agr. Dept. 



Farmers' bul. 17 : 5-20. 1894. 



Smith, E. F. The peach rosette. Journ. Myc. 6 : 143-148. 1891. 

 Smith, E. F. Additional notes on peach rosette. Journ. Myc. 7: 



226-232. 1893. 



