54 DISEASES OF GINSENG. 



by which its ravages may be controlled. Different crops require 

 different cultivation, and different diseases must receive different 

 treatments. 



From the grower's standpoint, the fungus and bacterial 

 diseases of ginseng fall into two classes: 1st., those diseases which 

 directly affect the roots of the plant and so cause its destruction 

 and a complete loss to the grower; 2nd., those diseases which effect 

 only the parts of the plant above ground, the leaves, stems, and 

 seed balls. This group of diseases usually produce only a partial 

 loss. This loss consists clueHy in the reduction of the growth of 

 the root and the destruction of the seed crop. 



The diseases directly effecting the root are the most destruc- 

 tive and at the same time the most difficult to combat. The fungi 

 and bacteria which are responsible for these disorders occur very 

 commonly in the soil, wiiere they usually grow upon dead and 

 decaying matter. Under certain conditions of heat and moisture, 

 which in most cases are unfavorable to the ginseng but favorable 

 to fungi or bacteria, they attaclr the living root, causing its des- 

 truction There are but two remedies, both preventive: 1st., the 

 disposal of excessive moisture. This may be accomplished by 

 thorough drainage or by means of constructing the shade arbor in 

 a manner that heavy rains will be kept from the beds. 2nd., 

 thorough sterilization of the soil before the roots are placed into 

 it. This can be most profitably done, perhaps, with steam, and 

 it has the added value of destroying insects and weed seeds. 



The diseases affecting the leaves, stems, and seeds alone, are 

 not numerous but unfortunately very widely distributed and very 

 destructive. These diseases are due chiefly to the attack of fungi 

 although a bacterial disease of the stems has been observed. These 

 diseases gain entrance into the healthy tissues, spreading rapidly 



