The Sterile Fungus Rhizoctonia. 77 



There was little or no injury due to the leaf-spot fungus, Phyllos- 

 ticta rhe'i^ and the trouble was evidently of other origin. Affected 

 leaves became dried and shrunken in appearance, and soon fell to 

 the ground. Where a iield was badly affected, the majority of hills 

 would show the trouble to the extent of at least a leaf or two. In 

 several instances, apparently from one-fourth to three-fourths of the 

 leaves were already dead. Fields thus affected showed noticeable 

 injury even from a considerable distance. 



Close by an affected field, or sometimes even contiguous to it, 

 might be found a field showing the trouble only to a very slight 

 degree. This may have been due to a longer culture of the rhubarb 

 upon one than upon the other area. 



An affected leaf breaks off readily just beneath the surface of the 

 ground, and it was found that dead or prostrate leaves had rotted 

 off in this region. The general appearance reminded one strongly 

 of the effect of Rluzoctonia upon beets. There was very little 

 superficial mycelium visible to the unaided eye. Microscopic exami- 

 nation showed hyplue of a Rliizoctonia both superficially, and also 

 immediately under the surface where the leaves were rotting. No 

 other fungus was at any time found abundantly associated with the 

 disease, and the Rhizoctoiiici was quite constantly present. 



Ox Ornamental Asparagus, Asparagus sprengeri. 



In May, 1900, a florist on Long Island called our attention to 

 dead patches in a large bench of Asparagus sprengeri in one of his 

 greenhouses. The plants were dead and the leaves, which were 

 gray and dry, had a tendency to cling to each other. Closer obser- 

 vation showed that the leaves were bound too-ether with brown 

 threads which proved to be Rhizoctonia liyphne. The disease 

 seemed to be unimportant, being conflned to small areas where the 

 foliage was kept unduly wet by tlie dripping of water from the 

 glass above. The roots of the affected plants were not examined. 

 Pure cultures of the fungus have been secured. 



Knowing that, in Europe, the garden asparagus, A. officinalis^ 

 is affected by a Rhizoctonia* root-rot we visited Mattituck, Long 

 Island, for the purpose of searching for the Rhizoctonia iu the 



* Rhizoctonia violacea Tul. 



