359 



of the ginseng gardens in New Yorl^. Tliis perfect stage developed from 

 sderotia on roots wliicli liad lain in the garden during the winter, very 

 near the surface of the ground. In the spring short stalks were sent up, 

 bearing large cup-shaped apothecia containing the asci with their asco- 

 spores. These spores when mature are shot up into the air to be dissem- 

 iimted by the wind and rain. 



Fig. 3. Black Hot. Cross and iLinniseclions of root and bud of diseased and liealtliy plants. 

 The blackening of the diseased roots will later extend to the center of the diseased root. Section of 

 healthy plant on right. (After H. H. Whetzel.) 



When once established in the garden the parasite apparently spreads 

 by the mycelium growing through the soil from one plant to another, kill- 

 ing all that come in its path. It is also spread by the tools used in weed- 

 ing or spading the beds, especially in tlie fall. Its distribution from one 

 garden to another is probably brought about by infested soil or perhaps 

 by spores being carried on the shoes of people visiting the various gardens, 

 or by the importation of diseased roots. 



A number of experiments were performed to determine if possible 

 some method of eradicating this disease by soil treatment. It was found 



