SHOOTS 
71 
they do not need to be exposed to the light. Stems hearing 
only scale leaves, therefore, hold no necessary light-relation, 
and may be subterranean as well as aerial. For the same 
J 
FIG. 62. A group of weeping birches, showing the branching habit and the peculiar 
hanging branchlets. The trunks also show the habit of birch bark iii peeling off 
in bands around the stem. 
reason scale leaves do not need to be separated from one 
another, but may overlap, as in the buds referred to. 
Sometimes scale leaves occur so intermixed with foliage 
