B. populifolia Marsh. Gray Birch. 



(ienerall_v distributed small tree of poor soil; abundant north to White Mountains, 

 diminishing northward ; abundant in old fields and pastures reverting to forest, also 

 occasional in bogs and in rocky scrub-forests of exposed slopes and summits up to 

 3,000 feet; hybridizes with B. f'af^yrifcra. 



B. caerulea-grandis Blanch. Blue Birch. 



Specimens have been collected in northern New Hampshire in Shelburne, Randolph, 

 and F'ranconia ; the taxon has been suggested as of hybrid origin ; polyploidy is known 

 to occur in Bctula and may be a complicating factor. 



E. minor (Tuckerm.) Fern. Dwarf White Birch. 



Frequent in alpine areas and heads of ravines (.>f Presidential and Franconia ranges: 

 h}-bridizes with B. glandulosa. 



B. papyrifera Marsh, var. papyrifera. Paper-or Canoe-Birch. 



The state tree of New Hampshire : common forest-tree throughout at low and 

 medium altitudes ; cool woods and slopes ; often replaced at higher altitudes by the 

 variety cordifolia. 



Co Ca Gr St Be Me Su Ro Hi Ch 



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