1b. Carpinus caroliniana subsp. virginiana (Marshall) Furlow, Syst. Bot. 12: 429. 1987.
American hornbeam, blue beech, musclewood, ironwood, charme de Caroline, bois de fer
Carpinus betulus Linnaeus [var.] virginiana Marshall, Arbust. Amer., 25. 1785; C. caroliniana var. virginiana (Marshall) Fernald; C. virginiana (Marshall) Sudworth 1893, not Miller 1768
Trees , to 12 m; trunks short, crooked, shallowly to deeply and often irregularly fluted, crowns broadly spreading. Bark bluish gray, smooth to somewhat roughened. Leaf blade ovate or elliptic to narrowly elliptic, (6--)8--12 × 3.5--6 cm, base narrowly rounded to cordate, margins coarsely and unevenly doubly serrate, teeth sharp and slender, secondary teeth almost as large as primary teeth, apex usually abruptly nearly caudate, but sometimes long, gradually tapered; surfaces abaxially usually moderately pubescent, especially on major veins, covered with numerous tiny, dark brown glands. Inflorescences: staminate inflorescences 2--6 cm; pistillate inflorescences 1--3 cm. Infructescences 4.5--12 cm; bracts 2.5--3.5 × 1.5--2.8 cm, lobes narrowly triangular, sharp-tipped. 2 n = 16.
Flowering late spring. In understory stratum in rich deciduous forest along stream banks, on flood plains, and on moist hillsides; 0--300 m; Ont., Que.; Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Ky., Maine, Md., Mass., Mich., Minn., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis.
Carpinus caroliniana subsp. virginiana is the familiar hornbeam of the Appalachians and interior forested northeastern North America. The leaves are distinctive in that they bear scattered dark glands on the abaxial surface. This subspecies hybridizes and intergrades with subsp. caroliniana where their ranges overlap in a broad band running from the Carolinas south to northern Georgia and westward to Missouri, Arkansas, and southeastern Oklahoma (J. J. Furlow 1987).