CHAPTER VIII 



PLANT FOOD 



It is not the land itself that constitutes the farmer's wealth, but ii 

 is the constituents of the soil which serve for the nutrition of plants. 



LlEBIO. 



71. The Soil and the Plant. In the last chapter we 

 studied a few points about the soil, and learned among 

 other things that the soil is the natural home of plants. 



We will now inquire 

 more especially what the 

 plant finds in the soil to 

 feed upon. 



Plants modify a part 

 of their body into what 

 we call roots, to take 

 hold upon the soil and 

 to secure certain kinds 

 of nourishment from it. 

 The roots of plants must 

 extend far enough into 

 the soil to enable their 

 thread-like outgrowths, 

 called root- hairs, to reach 

 the desired nourish- 



ROOT HAIRS ON WHEAT ROOTS. 



Through the walls of these tiny hairs 

 plant food passes to the root proper. 



ment ; and the soil should not be so hard as to prevent 

 them from penetrating into it for the required distance. 

 Nearly all the common farm plants feed from the " sur- 

 face soil." This is the part we plow and pulverize. 



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