74 



FARM DEVELOPMENT 



after 



the outer, recently developed ends of the main root are 

 active in absorbing water containing soluble plant food. 

 The older surfaces of the roots are covered with a tough 

 layer of barklike cells and these portions of the roots 

 serve only to transport water carrying soluble plant food 

 up to the stem, and to hold the plant in place. In 

 Figure 17 are diagrams showing the roots arising from 

 the stem, but not the branch roots, of corn at about 10, 

 20, 30 and 40 

 respectively, 

 planting. 



Figure 19 shows the 

 general spread of the 

 roots of a wheat plant. 

 The roots of other 

 cereal grains are quite 

 similar to those of 

 wheat. The roots of 

 our tame grasses also 

 penetrate to similar 

 depths. Clover roots go 

 a little deeper than the 

 roots of the grasses 

 and grains, while the 



rOOtS Of SOme perennial 



a.1 A />*-^^^. 1*1 ^.1^^.1-f^ 

 nelQ CrOpS, like alialia, 



j 11 j 



Under UnUSUally dry 



Figure 19. Crown and stem roots of a mature 

 wheat plant, from one seed. This plant stood 

 alone and developed over a dozen culms. There 

 are about 100 stem roots, which alone are here 

 shown, each of which had for some distance on 



, . . an average about eight branch roots to the inch, 



Conditions maV ?O tO a making a wonderful mat of roots in the soil. 

 ' ' J f Numerous roots penetrated to the depth of 4 feet 



depth of more than 20 that's 6 f s eet ead of the roota had a diameter of more 

 feet. But in all cases 



the plants, whether small, or even if as large as trees, 

 procure most of their food in the furrow-slice and upper 

 layers of subsoil. Since the furrow-slice and the part of 

 the subsoil just below it are the portions of the soil which 

 supply to the roots of crops the most congenial and 

 richest feeding zone, the aim of the farmer should be to 



