THE SOIL AND THE PLANT 



29 



have been formed. While these are forming, water has 

 been evaporating from the leaves, and consequently the 

 plant is insufficiently supplied, and droops. 



Would you not conclude that it is very poor farming to 

 till deeply any crop after the roots have extended between 



Clay and Gravel 

 Ground Water 



FIG. 19. DISTRIBUTION OF APPLE-TREE ROOTS 



the rows far enough to be disturbed by the plow or culti- 

 vator ? In cultivating between corn rows, for example, if 

 you find that you are disturbing fine roots, you may be 

 sure that you are breaking off millions of root hairs from 

 each plant, and hence are doing harm rather than good. 

 Fig. 20 shows how the roots from one corn row intertangle 



