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CHAPTER II 



THE ROOT 



20. The Root System. — The offices of the root are to 

 hold the plant in place, and to absorb water and mineral 

 substances. Not all roots, however, absorb water and mineral 

 nutrients. 



21. The entire mass of roots of any plant is called its 

 root system. The root system may be annual, biennial or 

 perennial, herbaceous or 

 woody, deep or shallow, 

 large or small. 



22. Kinds of Roots — 

 A strong leading central 

 root, which runs directly 

 downwards, is a tap-root. 

 The side or spreading roots are usually 

 smaller. Plants that have such a root 

 system are said to be tap-rooted. 

 Examples are red clover, beet, turnip, 

 radish, burdock, dandelion, alfalfa. 

 (Fig. 8.) 



23. A fibrous root system is one that 

 is composed of many nearly equal, slen- 

 der branches. The greater number of 

 plants have fibrous roots. Examples 

 are many common grasses, wheat, oats, 

 corn, and most trees. The bean in 

 Fig. 2 has a fibrous root system. 



24. Shape and Extent of the Root System.— The depth 

 to which roots extend depends on the kind of plant and the 



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Tap-root 

 of the 

 dandelion. 



