334 BULLETIN No. 189 [June, 



Sedum sp. 



A few plants of Sedum anglicum, together with several other spe- 

 cies of Sedum, were found diseased, in July, 1913, in the herbaceous 

 grounds. The progress of the disease was very slow ; few plants were 

 killed during the entire summer. For the most part, the fungus 

 seemed to live saprophytically at the base of the plant. It was also 

 found on healthy plants of this genus. About six species were planted 

 in a row in the garden, and all were affected in much the same way. 



SORREL, Rumex acetosella 



In June, 1914, a number of sorrel plants were found diseased in 

 an inoculated section in the greenhouse. The stems of the plants were 

 covered with the brown strands of mycelium, and a few of the leaves 

 were rotted off at the crown. Pure cultures of the diseased parts 

 yielded R. Solani in every case. 



SWEET PEA, Lathy r us odor at us 



During July, 1912, when the young sweet peas in the field were 

 about one-third to one-half grown, occasional vines showed evidence 

 of disease by turning yellowish, wilting, and finally drying up en- 

 tirely. An examination of the affected plants showed that they were 

 more or less separated from their roots near the surface of the ground. 

 Pure cultures of the diseased material yielded R. Solani in all cases. 



In November, 1913, several diseased seedling's were brought in from 

 the plant-breeding greenhouses. On close examination the stems 

 showed the characteristic lesions caused by Rhizoctonia. The same 

 trouble occurred in the floricultural greenhouses the past two seasons, 

 but in no case was it severe. 



During the winter of 1913, the writer was called to Chicago to look 

 over a range of greenhouses devoted to the growing of sweet peas. 

 Sweet-pea plants of all ages were seriously affected. Dead plants were 

 scattered thru the whole house. Close examination of the diseased 

 plants revealed the fact that Rhizoctonia was causing the trouble. 

 Apparently it started in the seed pans and continued to work until the 

 plants were ready to be discarded. The symptoms in each case were 

 the same yellowing of the foliage, followed by the wilting and dry- 

 ing up of the plants. Characteristic lesions, which finally cut the 

 stems off at the surface of the soil, could always be found on the dis- 

 eased plants. The root systems were much dwarfed. 



In 1908 Clinton 16 observed in Connecticut a damping-off of sweet 

 peas due to Rhizoctonia. Taubenhaus 130 ' 131 in describing a Rhizoc- 

 tonia rot of sweet pea at different stages, states that he found it quite 

 destructive to the plants when they are in the seedling stage. 



