Ill 

 1 Trees and How 



to Know Them 



OST ADULTS seem to take trees for granted, 

 but in the child's world they loom large. 

 They are natural play equipment, to be climbed for fruit or for 

 fun. City children are doubly grateful for them in summertime, 

 when the hot sun blisters the pavements and the only comfortable 

 place to play is under widespread, sheltering leaves. 



There are other reasons for appreciating trees because they give 

 homes to the birds and squirrels, and yield to man the wood that 

 he uses in so many ways. Even a young child cannot remain un- 

 moved by the beauty of the trees: the majesty of their boughs and 

 rugged bark, the changing colors of their leaves, the splendid 

 bounty of their fruit, blossoms, and cones. No wonder that most 

 children love the trees and delight in telling the seasons by these 

 living calendars. 



Tree Rings and What They Tell Us: You can find the record of a 

 tree's growth in the trunk or a branch that has been cut across. 

 There, in the wood, are the rings that mark each year of its life. 

 In adding to its girth the tree depends on a layer of cells called 

 "cambium," which lies just inside the protective bark. Each year 

 the cambium builds a layer of bark on its outer side and a layer of 

 wood on the inner side. 



During spring and early summer, when conditions for growth 

 are most favorable, wood cells develop. During late summer and 



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