320 BULLETIN No. 189 [June, 



Craig, Boston Market, Crane, Lawson, Lady Bountiful, Winsor. Sev- 

 eral of these varieties are still propagated by a few growers and with 

 good success, but the majority of them have been discarded. Of the 

 newer types no one seems to be more susceptible than the others. 



To Duggar and Stewart 30 is owed the discovery that Ehizoctonia 

 is the cause of stem rot of carnation. This they proved conclusively 

 in 1899 by inoculation experiments with pure cultures, repeated many 

 times. Duggar and Stewart state that this stem rot is one of the most 

 troublesome of the carnation diseases and probably occurs thruout the 

 United States wherever the carnation is grown. Stewart 123 " 124 at the 

 same time distinguished between two distinct diseases, both called 

 ' ' stem rot. ' ' One is caused by Rhizoctonia, and the other by Fusarium. 



Card and Adams 13 of Rhode Island studied methods of control of 

 both Fusarium and Rhizoctonia rots. They came to the conclusion 

 that the use of clean, fresh sand in the cutting bench helps to control 

 the fungus. They also found that stable manure does not favor the 

 spread of the disease. 



In 1902 Stone and Smith 129 reported carnation stem rot in Massa- 

 chusetts. Two years later Clinton 14 reported the presence of the 

 disease in Connecticut. In 1906 Heald 57 stated that it was found in 

 the field and in the greenhouse near Lincoln, Nebraska. Blake and 

 Farley 10 in New Jersey conducted a number of soil experiments for 

 the control of stem rot. 



CARROT, Daucus carota 



Occasionally R. Solani causes damping-off of carrot seedlings, 

 but the plants seem to be more susceptible later, when the fleshy root 

 is formed. Here the rot starts at the crown and works up into the leaf 

 bases. It also progresses into the interior of the fleshy root, as a rule 

 showing no signs on the exterior for some time. In some cases lesions 

 are found on the exterior of the carrot and on the larger secondary 

 roots where they branch from the fleshy part. 



Duggar and Stewart 32 were the first to find a disease of carrot due 

 to Rhizoctonia. In 1911 Heald and Wolf 59 reported from Texas the 

 Corticium stage of the fungus on carrot. They stated that the roots 

 were covered by white, ropy strands of the fungus, but that no serious 

 rotting was observed. 



CELERY, Apium graveolens 



A damping-off of celery seedlings in flats by Rhizoctonia Solani has 

 been observed in the Station vegetable-gardening greenhouses. The 

 symptoms are similar to those described for beets. 



During a search in the market in the winter of 1914 for leaf spot 

 and soft rot on celery, several bunches shipped from New York were 



