18 PLANT LIFE ON THE FARM. 



negative characters. Thus roots originate beneath the 

 surface, that is from within the tissues of the plant (endogen- 

 ous), and force their way out through the rind, as contrasted 

 with branches and leaves which originate on the surface 

 ^ exogenous). The extreme tip of the root, and of its sub- 

 divisions, is furnished with a minute " root-cap " of dead 

 tissue pushed off from the tip as it grows, as the feathers 

 ol a bird are removed during the moulting season. No 

 such cap exists at the end of a branch or leaf. Again, 

 while it is the office of a stem or branch to produce leaves 

 or scales, which are the representatives of leaves, no root 

 proper, as a rule, produces leaves or flowers. 



Botanists make a distinction between " true roots " 

 which are the direct outgrowth from the original " radicle " 

 of the germinating seedling, and, in fact, constitute its 

 direct continuation and "adventitious" roots, which spring 

 from the stem and branches, and which are only indirectly 

 derived from the primary root. For our present purpose 

 the distinction is unimportant. 



The root of a plant and its branches have different forms 

 and subserve different purposes. Whatever food is taken 

 up from the soil is taken up by them. They act as stays 

 and holdfasts, they serve as storehouses of nourishment. 

 Their form varies according to their use, their needs, the 

 competition with other roots, the conditions under which 

 they have to grow, and other circumstances, not forgetting 

 the heritage bequeathed to them by their predecessors 

 from generation to generation, for, like all parts of the 

 plant like the plant itself the root is the product of 

 what has gone before, adapted and modified by the exigen- 

 cies of the present. 



In this place we have to consider the roots chiefly in 



