THE EARTH'S BOUNTY 



duel for supremacy would commence between 

 the cottonwood and the walnut. 



A tree is made up of three distinct parts: 

 roots, trunk, and branches. The roots gather 

 food from the soil, which travels up the trunk 

 to the leaves, where it undergoes a sort of di- 

 gestive process, and is then distributed to the 

 different parts of the tree. Growth is, or 

 should be, made simultaneously in three direc- 

 tions: height, spread of branches, and circum- 

 ference of trunk and limbs. Height and 

 spread are increased by the new growth made 

 each season at the extremities. Circumference 

 of trunk and limbs depends on a glutinous sub- 

 stance which travels to all parts of the tree, be- 

 tween the real wood and the bark, and is really 

 composed of three layers; the inner and outer 

 ones being divided by a tissue- forming qual- 

 ity, technically called the cambium, which acts 

 upon the inner and outer substances, turning 

 the inner into wood and the outer into bark, 

 so adding a new coat to each every season 

 through a tree's growing years. There is an- 



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