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General Botany 



marked by a whorl of branches, and the age of a tree may readily 

 be estimated by counting the number of whorls on the stem. 

 Since the oldest branches are nearest the ground, they are the 

 longest, and the tree becomes cone-shaped as it grows. 



The terminal buds of the elm tree seldom survive the winter. 

 The lateral buds develop, and the main stem divides and sub- 



FiG. 6g. An American elm {Ulmus americana) . The terminal 

 buds of the elm seldom survive the winter, and the development of 

 the lateral buds causes the main stem to divide and subdivide until 

 it dissolves into the branchlets that form the crown. This tree 

 is growing in the Berkshire Hills, Massachusetts. It probably de- 

 veloped in a forest which was afterward cut down. 



