THE ROOT 27 



are plants which require two years to complete the 

 cycle of their lives. They usually produce during the 

 first year an abundance of leaves but no flowers. These 

 leaves manufacture plant food, in the form of starch or 

 sugar, in excess of the plant's immediate needs, and this 

 surplus food is stored away in the roots which usually 

 become very much enlarged. On the approach of 

 winter the leaves die down, but the roots remain in the 

 ground in a dormant condition. In the spring of the 

 succeeding year the plants put forth new leaves and 

 finally flower and produce seed, and, in carrying on 

 these processes, the store of food in the roots is 

 drawn upon so that by the time the seeds are ripe the 

 roots are practically exhausted. After the seeds have 

 been dispersed the plants die. This condition of things 

 may be well seen in such plants as beet, carrot, and 

 turnip. In agriculture man takes advantage of these 

 plants storing up food, and, collecting the roots at the 

 end of the first year, devotes their hoarded-up food to 

 his own uses. 



The observations made on seedlings have shown 

 that the roots of a plant usually arise from the radicle 

 of the little plant in the seed. In many plants, however, 

 roots arise not only in this manner but also from stems. 

 A good example is the ground ivy, which puts down 

 little bunches of roots from its stem as it trails over the 

 ground. It is obvious that these roots carry on the 

 ordinary work of absorption of water, because if the 

 main root dies or is cut away the plant is unaffected. 



In some plants the roots formed above ground are 

 also of use as supports ; thus in the Indian corn a number 



