THE ROMANCE OF OUR TREES 



heat, and cold assist in the removal of loosely coherent 

 barks. 



In different groups of trees the bark varies enor- 

 mously in thickness. We have stated that in the 

 Holly no true bark is formed; in the Beech it is firm 

 and smooth, and on trees several hundreds of years old 

 it is scarcely more than one half an inch thick; in 

 the Chestnut it is thicker, but in none of our common 

 trees is the bark of any great thickness. In the Big 

 Trees of California it attains its maximum develop- 

 ment, being in adult trees often as much as thirty 

 inches thick! 



But mere thickness has no bearing on the orna- 

 mental character of bark. The White or Paper Birch, 

 often felicitously called "My Lady of the Woods," 

 is known to all by its smooth white bark which 

 peels off in thin layers. No other tree has such pure 

 white bark though many Poplars have pale, yellowish- 

 gray bark, smooth except on the lower and older 

 parts. In the River Birch the papery gray-brown 

 bark clings in loose masses of irregular shape. The 

 Beech has smooth, grayish-white bark and in the 

 American species in particular the effect from a dis- 

 tance is like white mist. The Hornbeam also has a 

 pale gray bark like the Beech, but rather darker, 

 and on old trees it becomes shallowly fissured. The 

 Red, Silver, and Sugar Maples have smooth, pale 



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