LESSON IX 

 THE PLANT AND THE SOIL 



Roots are the parts of plants which grow in the soil. 

 Just as stems grow upward toward the light, so the 

 roots grow downward toward the moisture containing 

 the food supply in the soil. Some plants like the 

 common potato have underground stems ; and a 

 few plants like the peanut bear the fruit in the soil. 



Work of roots. - - The roots of plants serve two main 

 purposes : (i) they absorb the moisture with the 

 plant food dissolved in it ; and (2) they anchor the 

 plants to the soil and thus hold them in place. In 

 many plants the roots serve as organs in which to store 

 surplus food. These are of much importance to the 

 farmer. Examples of such plants are sugar beets, 

 cassava, sweet potatoes, turnips, carrots, and parsnips. 



Kinds of roots. Some plants have one main tap- 

 root growing straight down into the soil, the smaller 

 roots coming out from this main root. Beets, clover, 

 and alfalfa are some of the crop plants with taproots. 

 In other plants the roots branch near the surface of 

 the soil, as in many grasses. 



How deep roots grow. - - The depth to which roots 

 grow in the soil depends upon the kind of plants and 

 the condition of the soil. Buffalo grass in the West, 



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