CHAPTER SEVENTEEN 



EVERGREENS 



THE trees that we have studied up to this time are 

 deciduous; that is, they shed their leaves in the autumn. 

 But in many parts of the United States and Canada 

 evergreens are more common than the trees that lose 

 their leaves with the coming of the cold months. Each 

 type of tree is best suited for life under certain conditions, 

 and whether evergreens or deciduous trees are more 

 common in any given region depends on the prevailing 

 conditions of soil and climate. 



Definition of an evergreen. While any plant that 

 remains green throughout the winter is an evergreen, 

 and while in many parts of the United States we have 

 broad-leaved evergreen trees and shrubs like the mag- 

 nolia, holly, and rhododendron, yet we commonly mean 

 by an evergreen a tree or shrub with needle-shaped, 

 awl-shaped, or scaly leaves. The pine, spruce, cedar, 

 and fir are trees that belong to this group. They do 

 not, however, retain the same leaves as long as they live. 

 Under a pine or cedar tree the ground may be covered 

 with fallen leaves, but they fall a few at a time and not 

 all in a single season or year. 



The deciduous tree. In the spring a deciduous tree 

 spreads out a vast number of broad, thin leaves to the 

 light. All leaves give off water, and it is estimated 

 that a large birch tree must draw from the earth 100 

 gallons of water each day to prevent its leaves from 

 withering and drying in the hot sun. The delicate, 

 thin leaves of such a tree cannot endure cold, and in 

 winter it is possible for the roots of a tree to secure only 



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