Description of Native Trees 



32. Yellow Birch. Gray Birch. ( Betula lutea.) 

 Leaf: almost identical with 31 ; bark yellowish- or grajrish- 

 white, peeling horizontally in thin layers, closely curled. Twig- 

 bark less aromatic than in Sweet Birch. Range : northerly, in 

 damp woods. 



33. Red Birch. River Birch. (Betula rubra.) 

 Leaf: 2-3', simple, alternate, doubly-serrate, ovate, base and 

 apex pointed, whitish beneath ; bark a little inclined to peel hori- 

 zontally. Range: Massachusetts to Illinois, and south, near 

 water. (PI. IV.) 



34. Hop-Hornbeam. (Ostrya virginiana.) 

 Leaf : i'-4', simple, alternate, serrate, oval, apex tapering 

 (mudi like elm-leaf, but thin), foliage in flat sprays with very 

 small leaves intermingled. Fruit : white or pinkish, in hop-like 

 clusters ; August ; bark, with color and texture much as in white 

 oak. 



35. Hornbeam. Iron-wood. Water-beech. (Carpinus 



caroliniana.) 

 Leaf : almost identical with 34. Flower : in catkins. Fruit : 

 in clusters of small, 3-lobed leaves or bracts, one to each seed ; 

 bark, hard, smooth, ashy, ridged and horny ; low tree and shrub, 

 near water. (PI. VII.) 



36. American Elm. White Elm. (Ulmus americana.) 

 Leaf : 2'-4', simple, alternate, doubly serrate, oval or obovate, 



apex pointed, base usually oblique, smooth or slightly rough. 

 Fruit : roundish, hairy-edged ; April, May. Tree vase-shaped, 

 or broad-topped and drooping branches. (PI. V.) 



37. Slippery Elm. (Ulmus fulva.) 

 Leaf : 4-8', as in 36, but much larger and very rough. Fruit : 

 not hairy-edged ; April ; inner bark mucilaginous. (PI. V.) 



38. Corky White Elm. (Ulmus racemosa.) 

 Leaf : 2'-4', about as in 36 ; branches often corky-ridged. 

 Fruit : as in 36, but larger ; April, May ; near water, 

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