Diseases of the Plum 329 



the growing season would reduce the plum-leaf rust 

 to a minimum. 



Flyspeck fungus. I have several times observed, 

 especially on plums sent me from the southern states, 

 small areas thickly dotted with small black spots, look- 

 ing very much like small flyspecks. I have seen these 

 on nearly all the common species of plums, including 

 Prnnus aincricana, Primus maritima, and the Wayland, 

 Wildgoose and Miner groups. Occasionally the black, 

 specky appearance becomes so conspicuous as to at- 

 tract the eye and to detract from the appearance of 

 the fruit. It might possibly make a lot unsalable, 

 though I have never known it to become so severe. 



Specimens were examined by my colleague, Pro- 

 fessor L. R. Jones, who pronounces them of fungus 

 origin. The little dots are made up of masses of 

 branching dark-colored hyphae. This fungus is re- 

 garded by Professor Jones as being probably identical 

 with the one which causes the flyspeck on the apple. 



If this trouble should ever become of economic 

 importance, it would be worth while to try treating it 

 with bordeaux mixture. 



Phoma. What seems to be an entirely different 

 fruit-spot is mentioned and illustrated by Bailey, who 

 gives the following account of it:* "A fruit-spot has 

 been sent to me by T. V. Munson, Denison, Texas, on 

 the Golden Beauty. The disease is said to be serious 

 in some years. It does not injure the fruit greatly ex- 

 cept to disfigure it and to render it unmarketable. I 

 submitted the specimens to Professor J. E. Humphrey 

 of the Massachusetts agricultural college, who found 

 the disease to be a phoma, but the exact species could 

 not be determined. It is, no doubt, somewhat allied 

 to the black rot of the grape, and the treatment used 



*L. H. Bailey, Cornell Experiment station Bulletin 38:56. 1892. 



