THE STERILE FUNGUS RHIZOCTONIA AS A 
CAUSE OF PLANT DISEASES IN AMERICA* 

B. M. Duaaar AND F. C. Stewar®. 

‘SUMMARY. 
Rhizoctonia is a name given to certain sterile fungi occurring 
upon the subterranean parts of plants. Botanical literature 
contains numerous accounts of plant diseases in Europe caused 
by Rhizoctonia; but little has been written on such diseases in 
America. 
Finding that Rhizoctonia is common on various cultivated 
plants in America the authors have undertaken an exhaustive 
study of the genus. The bulletin is a preliminary report. It 
contains accounts of the discovery of the fungus on about 30 
species of cultivated plants in the United States. 
Rhizoctonia is the cause of a destructive root-rot of the sugar 
beet, a destructive stem-rot of the carnation, a leaf-rot of green- 
house lettuce, a leaf-rot of ornamental asparagus and a root-rot 
of the carrot; and is of common occurrence on stems and tubers 
of the potato. It is a frequent cause of damping-off of various 
seedling plants, such as beet, carnation, celery, lettuce, cab- 
bage, etc. It is also the suspected cause of disease in the bean, 
rhubarb, cotton, and some other plants. Further observations 
will probably show that many other plants are infested by it. 

*Reprint of Bulletin No. 186, 
Zi 
