[09 



( Chi iosporium carpophilum. ) 



A DESTRUCTIVE DISEASE AFFECTING NATIVE PLUMS. 



Ciadosporiuni catpjphiluiii^ (v. Thiimen.) 



By John Craig. 



During the past two years 

 many complaints have been 

 received from farmers and 

 fruit growers in regard to a 

 disease which hascaused their 

 red plums to shrivel and drop 

 quite suddenly when almost 

 mature. In many sections 

 during the past season the 

 crop has been an entire fail- 

 ure. As the disease appears 

 to be spreading, it would seem that in the near future very active 

 measures should be instituted to check its increase. 



Prof. L. H. Pammel, of the Iowa Agricultural College, who has 

 given the disease special study, has kindly supplied me with the follow- 

 ing facts, whiv-h I quote in his own words : — 



" My first acquaintance with this disease as affecting our cultivated 

 plums was in 1889.' 1 ne disease having appeared very destructive to 

 certain plums since that time, and the fungus has been on the increase. 

 This spotting is caused by a parasitic fungus, Cladosporiian car- 

 pophilum^ which is abundant on peaches, especially on the later varie- 

 ties. So injurious is it to certain varieties that Dr. Smith^ finds that it 

 not only injures the appearance of the fruit somewhat, but when very 

 abundant the flavour also. I have heard growers in Texas speak of it 

 as nothing serious, but to my mind there is no question that it greatly 

 lessens the crop, and also causes a cracking of the fruit as Dr. Smith 

 finds, making it especially subject to the attacks of Monilia fructigena. 

 Several other species ot Cladosporium are troublesome, the C. aiaime- 

 ritium, Ell. and Arth. is troublesome to cucumbers. Several species 



1. Meeting of Iowa Academy of Sciences, Sept. 5, 1890. 



2. Journal of Mycology, Vol. V., p. 32. 



/. 









ai:|'-'BRARY 



V 



r't^^<^ 



at 



V 



