AFTER-CULTUEE. 141 



signed, must be near the surface. If the roots are 

 severed with the plough, in dressing the crop, the 

 plants are deprived of a portion of their nourishment ; 

 and if they are buried deep by hilling, the plant is 

 partially exhausted in throwing out a new set near 

 the surface, where alone they can perform all their 

 offices." 



