BETULACEAE 



Eastern Hophornbeam 



Ostrya virginiana (Mill.) K. Koch 



HABIT. A small tree 20-40 feet high and 8-18 inches in 

 diameter (max. 65 by 3 feet) ; with rounded crown and slender, 

 pendulous, often contorted branches, 



LEAVES. Alternate; simple; oblong-ovate; 3-5 inches long 

 with 11-15 pairs of veins; deciduous; acuminate; sharply doubly 

 serrate margins; thin and tough; dull dark green above, paler 

 and somewhat hairy below. 



FLOWERS. Regular; monoecious; perianth absent; appear- 

 ing with leaves; staminate in long, drooping, cylindrical aments 

 in clusters of 3, each flower containing 3-14 stamens crowded 

 on a hairy receptacle; pistillate in erect, loose, paired aments, 

 each flower enclosed in a hairy, sac-like involucre. 



FRUIT. Smafl ('4 inch), 1-celled, 1-seeded, ovoid, flat, 

 unwinged nut; enclosed in enlarged (1 inch), pale, membran- 

 aceous, involucre of flower; in loose, suspended strobiles l-lYz 

 inches long, resembling clusters of hops. 



TWIGS. Slender; round; red-brown becoming dark brown. 

 Winter buds: terminal absent, lateral V^-!4 inch long, ovoid, 

 acute, with characteristic longitudinal striations on the bud 

 scales which have a greenish base and brown top. 



BARK. Thin; gray-brown; broken into small, shaggy plates 

 which give it characteristic shreddy appearance. 



WOOD. Very heavy, hard, and strong; unimportant; resem- 

 bling hickory and known as ironwood; little used. 



SILVICAL CHARACTERS. Tolerant; slow-growing; lateral 

 roots; varied sites, but typical on dry slopes. 



Knowlton Hophornbeam 



Ostrya knowltonii Gov. 



This rare, local tree is found in mountains and canyons of 

 western Texas, southeastern New Mexico, northern Arizona, 

 and southeastern Utah. It difl'ers from 0. Virginiana in having 

 leaves 1-2 inches long with 5-8 pairs of veins. 



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