CHAPTER II 



THE SOIL AND THE PLANT 



SECTION VIII ROOTS 



You have perhaps observed the regularity of arrange- 

 ment in twigs and branches. Now pull up the roots of 

 some plant, as for example sheep sorrel, Jimson weed, or 

 some other plant. Note the branching 

 of the roots. In these there is no such 

 regularity as is seen in the twig. Trace 

 the rootlets to their finest tips. How 

 small, slender, and delicate they are ! 

 Still we do not see the finest of them, 

 for in taking the plant from the ground 

 we tore them away. In order to see 

 the real construction of a root we must 

 grow one so that we may examine it* 

 uninjured. To do this, sprout some 

 oats in a germinator and allow them to 

 grow till they are two or more inches 



high. Now examine the roots and you 



. ...., . FIG. 16. ROOT HAIRS 



will see very fine hairs, similar to those 



J ON A K.ADISH 



shown in the accompanying figure, 

 forming a fuzz over the surface of the roots near the tips. 

 This fuzz is made of small hairs standing so close together 

 that there are often as many as 38,200 on a single square 



27 



