'38 



ECONOMIC PLANTS 



inches above the ground, they and their roots are sepa- 

 rated. from the sweet potato and set out in the field or 

 garden, two feet apart in rows four feet apart. A sec- 

 ond growth of sprouts will soon spring from the same 

 sweet potatoes, and these are also transplanted. The 

 sets in the field are also cut and transplanted as soon 

 as the vines have grown to be about twelve inches 

 long, a small number of sweet potatoes thus serving to 

 stock a considerable area. Sweet potatoes require the 

 same careful cultivation, manuring, and clean soil that 

 potatoes need. Good crops show a yield from 200 to 

 300 bushels an acre. 



Beets are of two varieties, the mangel-wurzel and 

 the sugar beet. The former are used largely for stock 

 food. As they require a rich loam, manure must be 



FIG. 122. Mangel-wurzels. 



