THE STORY OF PLANT ROOTS. 



Professor Melvillk Gumming. 



Pull up a plant, and you will notice three distinct 

 parts — the leaves, the stem, and roots. The stem 

 and the leaves are the parts above the earth ; 

 the roots, the part that is buried in the earth. 

 To the tarmer, the roots, being the part in the soil, 

 are in many ways the most important part of the 

 plant. Sometimes he grows such roots as turnips, car- 

 rots, and beets for his own use, and then, of course, 

 they are very important ; but even when he grows hay 

 or wheat or corn, he can do so only by preparing a good 

 soil in which the roots may grow. With all his intel- 

 ligence he cannot affect the sunshine and the air which 

 surrounds the stem and leaves ; but he can by good 

 cultivation so improve the soil that the roots can de- 

 velop in the very best way, and by improving the 

 growth of the roots he can improve the growth of the 

 Fig. 7. Corn Seedling, show- other parts of the plant. Since we are going to 

 ing leaves, stem, and roots, ^^^^j^. ^^^ ^^^^^ ^^^^ ^^^ farmer's standpoint, we will 



dig down into the earth and see what we can ot the roots of plants. 



What are the roots in the ground for ? They hold the plant in place. 

 Have you ever walked against a heavy-blowing wind and felt its force, 

 sometimes so strong that you could scarcely stand up ? If you have, you 

 can in part imagine the force with which the wind sometimes blows 

 against a tree that is ten or fifteen times as big as you are. The roots 

 of a large oak or maple or pine tree must be very securely fixed in the 

 ground to stand the great strain from such winds ; and although most 

 of the plants grown on the farm are very much smaller than trees, yet 

 even they must be very securely held in the soil by their roots. 



Not only do roots serve as anchors, but also as the feeding and 

 drinking organs of plants. Plants, as well as animals, must have food 

 and water in order to live and grow ; but, unlike animals, they have 

 more than one mouth through which to take in food and drink. By 

 means ot their roots they take in all the water they need and all the food 

 which the soil can give them. However, plants do not get all their food 

 from the soil. Part of it they get from the air, and the leaves are the 

 mouths for this food. It will be very interesting, a little further on, to 

 see why these two feeding organs, the leaves and the roots, are so 

 diff'erently formed. 



Yet another purpose do roots serve in the life of some plants. As 

 you all know some plants, called annuals, live only one year. Others, 

 called biennials, live two years ; and still others, called perennials, live 

 many years. Plants belonging to the last two classes must have some 

 means of stormg up food for the winter months. Perennial plants, such 

 as trees and shrubs, generally develop strong stems and branches and 

 store up fo( d in them. But the stems and branches of biennials and 



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