DISEASES OF SPECIAL CROPS 



89 



Hypochnose ^ ( Hy- 

 pochnus ochroleuca, 

 Noack). — Hypoch- 

 nose is principally a 

 leaf affection causing 

 blight and loss of the 

 leaves, and thereby 

 weakening the vital- 

 ity of the tree. 



Superficially this 

 disease resembles the 

 bhght, with which it 

 might be confounded 

 by the casual ob- 

 server. It may be 

 readily distinguished, 

 however, by two char- 

 acters: first, the 

 manner in which the 

 leaves droop and mat 

 together, which is 

 quite different from 

 the habit of the blight, 

 the leaves of which 

 neither droop nor 

 mat ; second, by the 

 presence of small scle- 



rotia, white when young, cinnamon-brown when mature, 

 upon the twigs adjacent to the affected leaves. These 

 sclerotia usually measure about 2-3 mm. in diameter. To-= 



1 Stevens, F. L., and Hall, J. G., Ann. Mycol. VII, 49, 1909. 



Fig. 34.— Hypochn 



ise, showing matting of leaves. 

 Original. 



