126 HANDBOOK OF NATURE STUDY 



In the lessons which follow, only a few trees have been 

 described at length, to suggest how all should be studied, 

 Very brief descriptions of the others are given in order to 

 gain space, but the language of these outlines should not be 

 used in the class-room. 



After a tree has been studied in its different conditions, 

 the parts of its annual history should be connected into a 

 whole; and when the subject of trees has been completed, 

 different pupils might write out, in the best English they 

 command, the annual history or the life history of different 

 trees. 



The following books would be helpful in the description and 

 determination of trees : 



K. C. Davis. Key to the Trees of Minnesota in their Winter Con- 

 dition. 



Knobel. Trees and Shrubs of New England. 



NewhalL The Trees of Northeastern America. This includes some 

 naturalized species and all the native trees of Canada and the 

 northern United States east of the Mississippi. The last two books 

 are illustrated, and the key is based on the shape of the leaves. 



If you have access to a public library, consult Sargent, Silva of North 

 America, the American classic on trees. 



