SURROUNDINGS OF THE HOME 



269 



TREE INCREASES EACH 

 YEAR IN HEIGHT AND 

 SPREAD OF BRANCHES 

 BY ADDING NEW GROWT 



OF TWIGS. 



INNER BARK CARRIES 



PREPARED FOOD FROM 

 LEAVES TO CAMBIUM 



AlR SUPPLIES CARBON. THE PRINCIPAL 

 FOOD OF THE TREE. TAKEN IN ON 

 UNDER SURFACE OF LEAVES. 



LEAVES PREPARE THE FOOD 

 OBTAINED FROM AIR AND 

 SOIL AND GJVE'OFF 



MOISTURE. 

 , BY TRANS^ 



PIRA ~%j LIGHT AND HEAT 



ION .^5* NECESSARY FOR 

 CHEMICAL 

 CHANGES 



HEARTWOOD (INACTIVE) 

 GIVES STRENGTH 



THE BREATHING PORES OF" 

 THE ENTIRE TREE ;ON LEAVES, 

 TWIGS.BRANCHES, TRUNK AND 



ROOTS, TAKE IN OXYGEN. 



FLOODING. POISONOUS GASES 



OR" SMOKE MAY KILL A TREE . 



SAPWOOD CARRIES SAP 

 FROM ROOTS TO LEAVES 



CAMBIUM (MICROSCOPIC) 

 BUILDS THE CELLS 



OUTER BARK PROTECTS 

 TREE FROM INJURY 



SURFACE ROOTS 



SURFACE: 

 ROOTS : _ 



ROOTS^~ 



: Root TIPS OR 



ROOT HAIRS 

 TAKE UP WATER 

 CONTAINING SMALL QUAN- 

 TITY OF MINERALS IN SOLU- 

 TION 



FIG. 86. Structure of tree, and functions of its parts. 



