3o8 Diseases of Greenhouse Crops 



Control. All diseased material should be de- 

 stroyed by fire. Some florists recommend spraying 

 or sponging the leaves with potassium permangan- 

 ate. 



Anthracnose 



Caused by Colletotrichutn kentia Hals. 



This disease has been first studied by Halsted* 

 as it was found by him to attack the various orna- 

 mental Kentias. 



Symptoms. The disease appears as watery spots, 

 which soon become dry (fig. 61, h) and within 

 which are formed the salmon-colored acervuli which 

 contain numerous setae. In time the dead tissue 

 falls out, leaving holes in which remain the hard, 

 woody vessels which run across. This disease also 

 attacks young seedlings and cripples them beyond 

 any commercial value. The following Kentias are 

 subject to the attacks of the anthracnose: Kentia 

 belmoreana, K. canterburyana, and K. fosteriana. 



Control. It is difficult to keep this disease in 

 check unless the infected material is removed and 

 destroyed by fire. Spraying the plants weekly with 

 a standard fvmgicide will keep the anthracnose in 

 check. 



ExospoRiuM Leaf Spot 



Caused by Exosporium palmivorum Sacc. 

 Symptoms. The disease is characterized by mi- 



• Halsted, B. D., New Jersey Agr. Expt St., Fourteenth Ann. 

 Kept: 407-409, 1893. 



