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LESSONS IN AGRICULTURE 



Root-hairs. On the roots of the corn in our germina- 

 tion test box, we saw great numbers of fine root-hairs. 

 These are the principal feeding organs of the plant. 

 They have the power to transfer the water and the 

 plant food from the soil to the rootlets. If water does 

 not exist as capillary water in the soil, the root-hairs 

 are unable to do their work. 



Purpose of roots. The root system in all its mod- 

 ifications serves three purposes to the plant: 



(1) It absorbs and conducts water and plant food 

 dissolved in the water. 



FIG. 81. ROOT SYSTEMS OP PLANTS 



(2) It reaches long distances in the ground and thus 

 holds the plant firmly in its place. 



(3) It furnishes a storehouse for much food material, 

 as in the case of the radishes, beets, and turnips. 



Practical Exercises 

 1. A Study of Eoots 



Dig up a clover plant and remove the soil from it. 

 Observe that it has a strong central root which joins 

 the stem. Make a drawing of the clover root system. 



Dig up a single timothy plant with as many of its 



