INTRODUCTION 



trees in winter as in summer. The differences 

 in the various families of trees, once these are 

 understood, are marked enough to make family 

 relationships easy to recognize at this season of 

 the year. Nor will it be found difficult, once 

 the characters peculiar to each kind of tree are 

 fixed in the mind of the observer, to determine 

 the various species; and these winter charac- 

 ters are often more constant and stable than 

 characters derived from the flowers, the shape 

 of the leaves, or from the size and shape of the 

 fruits, on which dependence is usually placed 

 for the identification of trees. 



Each species of tree has its peculiar habit, 

 which is best seen in winter and which it 

 usually retains under normal conditions. The 

 character of the bark rarely changes much on 

 individuals of the same age, although the bark 

 of old trees is usually very different from the 

 bark of young trees of the same species; and 

 the color of the branchlets and the form and 

 size of the winter buds generally afford certain 

 means of determining closely related trees. 



In each kind of tree there is, in addition to 

 its general habit, which with a little practice is 

 frequently sufficient to make the recognition of 

 a particular species easy, some special character 

 which enables the student to confirm his deter- 



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