CHAPTER XI 

 PLANTS IN RELATION TO MAN 



I. THE SOIL AND PLANTS 



219. Importance of the soil. An old fable represents a 

 dying father telling his sons of a wonderful fortune hidden 

 within a foot of the surface of the garden. They, supposing 

 that his words referred to a chest of gold and jewels, began to 

 dig up the garden. When they had dug over the whole garden 

 and still found no treasure, the eldest brother suggested that 

 they should not lose all the profit of their labor, but plant the 

 garden thus tilled. In due course they gathered a wonderful 

 yield and began shrewdly to suspect that it was this to which 

 their father referred as their treasure. Then they labored to 

 put all their land under cultivation and thereby won wealth 

 beyond expectation and greater in value than a chest of gold 

 and precious stones. 



This fable is more significant to-day than ever before. It 

 points clearly to the ultimate source not only of a large part 

 of human wealth, but also of all the things that supply our 

 daily needs. The surface of the earth with its thin skin of 

 soil only a few feet in depth produces the plants upon which 

 we depend for food and for materials to provide clothing and 

 shelter. The soil and its use provide not only the foundation, 

 but the support of human life and society. 



A study of soil. What is the soil ? We may learn much 

 about it through formal descriptions in books, but we shall 

 learn a great deal more by studying the soil directly and finding 

 out for ourselves its essential characteristics and composition. 



454 



