5. Populus deltoides W. Bartram ex Marshall, Arbust. Amer. 106. 1785. (as deltoide).
Eastern cottonwood, cotonier
Plants to 55 m, 35 dm diam.; moderately to strongly hetero-phyllous, (often 2 or more trunks near base). Bark light brown, deeply furrowed. Branchlets yellow-brown, becoming tan by third year, round or 5-angled, coarse or not, (1-)2-3.5(-6) mm diam., glabrous or thinly long-hairy. Winter buds greenish yellow, glabrous or stiffly hairy, resinous (resin yellow, moderately fragrant); terminal buds (6-)8-15(-21) mm; flowering buds separated on branchlets, (8-)14-20(-28) mm. Leaves: petiole distally flattened at right angle to plane of blade, (1-)3-8(-13) cm, about equaling blade length, (glabrous); blade broadly triangular-ovate, (1-)3-9(-14) × (1.5-) 3-9(-16.5) cm, w/l = 4/5-6/5, base truncate to cordate or broadly cuneate, basilaminar glands 0-6, round or tubular, margins translucent, ciliate, apex abruptly short- or long-acuminate, surfaces grayish green to bright green, glabrous (or visibly pilose only at emergence); preformed blade margins coarsely crenate-serrate midblade, teeth (3-)5-15(-30) on each side (graded, rounded), sinuses (0.4-)0.7-5(-7) mm deep; neoformed blade margins crenate-serrate, teeth (10-) 25-40(-55) on each side (graded), sinuses (0.1-) 0.5-1.5(-3) mm deep. Catkins loosely (3-) 15-40(-55)-flowered, (0.7-)5-18(-24 in fruit) cm; floral bract apex deeply cut, not ciliate. Pedicels 1-13(-17 in fruit) mm. Flowers: discs saucer-shaped, not obviously oblique, entire, 1-3(-4) mm diam.; stamens 30-40(-55); anthers truncate; ovary (3- or)4-carpelled, ovoid; stigmas 2-4, platelike, spreading. Capsules ovoid, (4-)8-11 (-16) mm, glabrous, (3- or)4-valved. Seeds (3-)7-10 (-23) per placenta. 2n = 38.
Subspecies 3 (3 in the flora): North America, n Mexico.
