202 The Sugar-Beet in America 



spread and unite till a great part of the surface of the beet 

 may be covered. 



On potatoes the disease may be controlled by treating 

 the tubers, but this treatment is not applicable to beets. 

 Beets should not be planted on land known to be infected 

 with scab, and particular care should be taken not to 

 follow scabby potatoes with beets. 



Soft-rot {Bacterium teutlium Met.). 



This rot has done considerable damage in Nebraska and 

 in a number of other states where beets are grown. " It ^ 

 consists of a rotting away of the lower portion of the root, 

 the crown and leaves remaining normal except in the most 

 severe cases, when the outer leaves may fall. The rotted 

 portion is honeycombed with cavities which are filled with 

 viscous, colorless, sour-smelling fluid which exudes on 

 pressure. The decayed tissue is usually yellowish gray. 

 The rot seldom appears above the surface of the ground. 

 Young beets are not susceptible. The disease is favored 

 by damp surroundings, as poorly drained soil. In some 

 cases, large damage is known to result, sometimes fully 

 90 per cent of the crop being affected. It is inadvisable, 

 if the disease is noted, to grow beets in wet soil." 



The moisture condition of the soil seems to have great 

 influence on soft-rot. 



Beet-rust {Uromyces betas Kuhn). 



This rust, which has been known in Europe for a half 

 century, is found in some American beet fields, particularly 



1 Stevens, F. L., and Hall, J. G., "Diseases of Economic 

 Plants." (1910), p. 209. 



