144 



MANUAL OF FRUIT DISEASES 



REFERENCES 



Salmon, E. S. A canker of apple trees caused 



by the brown rot fungus. Gard. Chron. 



3 : 47 : 327. 1910. 

 Molz, E . Ueber die Bedingungen der Entstehung 



der durch Sclerotinia erzeugten Schwarzfaule 



der Apfel. Centralbl. f . Bakt. 2:17: 175- 



188. 1906. 

 Salmon, E. S. A canker of apple trees caused by 



the brown rot fungus. Southeastern Agr. 



Col. (Wye) Kept, on Econ. Myc. 1909-1910 : 



33-35. 1910. 

 Aderhold, Rud. Uber eine vermuthliche zu 



MoniKa fructigena Pers. gehorige Sclerotinia. 



Deut. Bot. Ges. Ber. 22 : 262-266. 1904. 



ROUGH-BARK 

 Caused by Phomopsis Mali Roberts 



This disease is known to growers as rough- 

 bark. It attracted more than usual atten- 

 tion in Virginia in 1909. The more careful 

 observers have noted the disease on the 

 Yellow Newtown ; the trouble is so common 

 in Virginia on this variety that at times the 

 roughness is regarded as a character, and is 

 used as a mark of identification. While not 

 common or serious on any other varieties, it 

 is known to affect the York and Winesap. 

 It has recently been found on apples and 

 pears in California. 



Symptoms. 



The rough-bark disease is most serious on 

 the smaller branches of old neglected trees. 

 The one-year-old twigs are very susceptible, 

 while the current year's growth escapes. Sometimes larger 

 branches and even the trunks are affected. The diseased 





FIG. 38. Brown- 

 rot canker of apple, 

 caused by Sclerotinia 

 fructigena (specimen 

 from England) . 



