Twig has sweet wintergreen taste when chewed

Back Yellowish and the bark of older trees is peeling off. -- Yellow Birch

Bark black and broken off into plates on older tree. -- Black Birch

All trees
- Tree having broad leaves.
  - leaves simple.
    - Leaves and branches alternately arranged.
      - No thorns on branches.
        
        Only one type of leaf on tree.
        
        Leaf unlobed.
        
        Leaf has teeth on th edge.
        
        Leaf-stem is round.
        
        Leaves not heart-shaped and not very wide, but may be long.
        
        Teeth on edge of leaf many and small.
        
        No stipules at the base of the leaf-stem.
        
        Bark rough and black or yellowish.
        
        Twig has sweet wintergreen taste when chewed.

This key was developed by "bt" in June 1982. It was put into HTML format by Stephen Ostermiller in July 1997. Copies of the entire guide in zip format that may be taken to camp on a laptop are available to those who write.