HOW THE ROOT GETS FOOD FROM THE SOIL 11 



any position you like, and it will always bend so as to 

 grow downward (this is due to gravity). Try the ex- 

 periment with seeds lying on the top of moist soil. 

 Keep them covered with a tumbler turned upside down, 

 so that the roots do not dry up. 



Where there is a main root growing straight down, 

 it is called a tap root, and often this may go down many 



FIG. 7. Roots of an oak tree. 



feet in search of moisture. Such plants as corn and 

 grasses have no tap root; their roots spread out near 

 the surface. Such plants make early and rapid growth, 

 but cannot stand drought like plants with taproots, nor 

 get food from deep down in the soil. 



The small rootlets which spring from the side roots 

 grow in all directions, searching every inch of soil for 

 water and food. 



