50 SWEET I'OTATO CULTUllE. 



We know that these tubers can be kept in excellent 

 condition until late in the spring, by the means above 

 recommended, but fodder-stacks are now seldom made so 

 as to admit a potato i)it, as it is the custom to cut up 

 corn with stalk and fodder, and have a solid stack. But 

 shelters and pits could bo chcajily made in the same shape 

 as an old-fashioned fodder-stack, that would answer the 

 same purpose. 



CHAPTER XV. 

 DISEASES AND ENEMIES OF THE SWEET POTATO. 



The most formidable enemy to the young plants in the 

 hot-bed, appearing later in the field soon after trans- 

 planting, is the "black root," "black rot," or "black 

 shank," familiar to grow-ers. It is a kind of blight or 

 gangrene of the roots, and tlie general impression is that 

 it proceeds from over-stimulation by heat and ammonia, 

 from the material used in the bed ; it sometimes, although 

 rarely, appears in the plants raised under sash in cold 

 frames. Soon after setting the plants, we find they do 

 not grow, leaves look yellow, spotted and sickly ; pulling 

 up the set, we find the cause in the black stems undei' 

 the earth, in which there is very little life and circula- 

 tion. The remec'-; is of course prevention, and a care- 

 ful rejection of all plants affected with black spots on 

 the stems when drawn from the propagating beds. 

 When the plants are healthy, setting over heating 

 manure, may cause it, or cold, unfavorable weather su- 

 pervening soon after they are set, so that plants can- 

 not grow, is supposed to be another cause of this disease. 



