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AMERICAN HOP HORNBEAM. 

 Ostrya virginiana, (Miller) K. Koch. 



GENUS DESCRIPTION This genus comprises about 4 species which are widely distributed 

 in the northern hemisphere. Two species are native to America and 2 to the eastern hemisphere. 

 One of the American species is more limited in its distribution than any other known tree, 

 being found only in the Grand Canon of the Colorado River in Arizona while the other 

 American species is rather widely distributed over the eastern part of the country., 



FORM Usually attains a height of 20-30 ft. with a diameter of li ft., but may reach a 

 height of 60 ft. with a diameter of 2 feet. Crown high, open, and very broad, formed by 

 widely spreading often drooping branches with ascending branchlets. 



BARK Grayish-brown, thin, roughened by loose flattish scales which are loose at the ends. 

 See Fig. 54. 



TWIGS Slender, tough, dark reddish-brown, zigzag, at first hairy and green, later smooth, 

 lustrous, dark brown. 



BUDS Alternate, ax'llary; terminal bud absent; ovate, 1 of an inch long, sharp-pointed, 

 distinctly divergent, slightly pubescent, smooth, gummy, covered by about 8 visible, longi- 

 tudinally-striated, 4-ranked scales which increase in size from the base towards the apex. 



LEAVES Alternate, simple, ovate-oblong, acute at apex, doubly-serrate on margin, rounded 

 or heart-shaped or wedge-shaped at base, 3-5 inches long; dull yellowish-green above, paler 

 green below. 



LEAF-SCARS Alternate, small, flattened, 2-ranked, with usually 3 small bundle-scars. 



FLOWERS Appear about April with the leaves. Staminate aments appear about midsummer 

 usually in about 3s at the end of the twigs and persist during the winter; they are stiff, 

 hairy, about ! of an inch long, becoming about 2 inches long in spring and covered with 

 reddish-brown scales. Pistillate flowers appear in erect aments, each one inclosed in a hairy 

 bladder-like bract. 



FRUIT A small Hat nutlet, inclosed in an inflated bladder-like bract which is covered at 

 the base with long hairs irritating to the skin. Bracts arranged in hop-like, pendant clusters 

 which fall during winter and leave the persisting naked stalk. 



WOOD Diffuse-porous; rays indistinct; strong, hard, durable, light brown to white. Weighs 

 about 51 Ibs. per cubic foot. Used for fence posts, tool handles, and mallets. 



DISTINGUISHING CHARACTERISTICS The American Hop Hornbeam, also known as Ironwood, 

 Leverwood, and Deerwood, can readily be recognized by its thin grayish-brown bark which peels off 

 into narrow flat scales often loose at both ends and only attached in the middle. The hop-like 

 clusters of sac-like fruit are also peculiar, which usually fall before winter but the stalks 

 to which they are attached often persist. la winter the very slender interlacing branches, the 

 staminate catkins usually occurring in 3s at the end of the twigs, the small 2-ranked leaf- 

 scars with 3 bundle sea rt, and the small reddish-brown buds with 4-ranked scales are charac- 

 teristic. The autumnal color of the leaves is yellow while that of the closely related American 

 Hornbeam is brilliant orange to deep scarlet. The hardness of the wood is also distinctive. 

 The wood is about 30 per cent, stronger than White Oak. 



RANGE Cape Breton Islands to Florida, west to Minnesota and Texas. 



DISTRIBUTION IN PENNSYLVANIA Found locally throughout the State but nowhere 

 abundant. Usually mixed with other species. Rarely conspicuous In the composition of 

 the forest. 



HABITAT Prefers dry gravelly slopes and ridges, occasionally moist situations. Usually 

 seeks cool and shaded situations, and Is never found in pure stands or groups, but occurs 

 singly in mixture, often as an undergrowth of Oak, Maple, Chestnut, and other forest species 

 common to its range. 



IMPORTANCE OF THE SPECIES The American Hop Hornbeam produces a valuable wood and 

 grows rapidly, but its solitary habits as well as its silvicultural characteristics and the relatively 

 small size which it attains, do not recommend it for forestry purposes. It is well adapted 

 for planting in lawns and parks. 



