GATHERING FOOD AND MOISTURE 19 



many of which have a delicate hair-like growth. The total 

 length of all the roots of some plants may be many times the 

 total of the stem and branches. The total length of all the roots 

 of a mature oat plant are said to aggregate 154 feet, and those 

 of a mature corn plant 1320 feet. Of course, no one root is 

 likely to be more than a few feet in length. However, some 

 plants are known to produce individual roots of considerable 

 length. The alfalfa is said to produce single roots as much as 

 31 feet in length and the mesquites of the dry western plains 

 are said to produce individual roots of as much as GO feet in 

 length. The greater the root surface, the greater the amount 

 of food and water that can be secured by the plant. Of course, 

 an increase of the root system is usually necessary to an in- 

 crease of the part above ground. 



The roots serve many purposes in the life of the plants, but 

 these duties are somewhat variable for different plants. The 

 most important functions are as follows : anchorage, gathering 

 of water and food, storage of water and food, and in some cases 

 for climbing. The roots serve as an anchor by which the plant 

 is held in place. When we try to uproot a plant or think of the 

 terrific wind storms to which our trees are frequently exposed, 

 we can appreciate the importance of a secure anchorage. Some 

 of the large trees of California are said to be thousands of 

 yeaxs old and, after battling with the stonns of ages, are still 

 standing, objects of great admiration. 



Gathering Food and Moisture. — We know that the roots 

 are organs through which water and much of the food materials 

 enter the plant, but we have very little idea of the amount of 

 water and food necessary for plant growth. Our land plants 

 require enormous quantities of water (Page 105), which must 

 enter through the roots. Therefore, it is necessary for the 

 roots to spread through the soil in such a manner as to reach 



