Description of Native Trees 
32. Yellow Birch. Gray Birch. ( Betula lutea.) 
LEAF: almost identical with 31; bark yellowish- or grayish- 
white, peeling horizontally in ¢hin 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: 1-4’, simple, alternate, serrate, oval, apex tapering 
(much like elm-leaf, but thin), foliage in flat sprays with very 
small \eaves 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: incatkins. FRUuIT: 
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. (Pl. 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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