Habitat and Range.—Near streams, river bottoms, and low, damp woods.
Ontario.
Maine,—apparently restricted to York county; New Hampshire,—Merrimac valley towards the coast; along the Connecticut as far as Walpole; Vermont,—scattering along the river shores, quite abundant along the Hoosac in Pownal (Eggleston); Massachusetts,—occasional; Rhode Island and Connecticut,—rather common.
South to Florida; west to Minnesota, Nebraska, Kansas, and Texas.
Habit.—A tree of the first magnitude, 50-100 feet and upwards in height, with a diameter of 3-8 feet; reaching in the rich alluvium of the Ohio and Mississippi valleys a maximum of 125 feet in height and a diameter of 20 feet; the largest tree of the New England forest, conspicuous by its great height, massive trunk and branches, and by its magnificent, wide-spreading, dome-shaped or pyramidal, open head. The sunlight, streaming through the large-leafed, rusty foliage, reveals the curiously mottled patchwork bark; and the long-stemmed, globular fruit swings to every breeze till spring comes again.
The lower branches are often very long and almost horizontal, and the branchlets frequently have a tufted, broom-like appearance, due probably to the action of a fungous disease on the young growth.
Bark.—Bark of trunk and large branches dark greenish-gray, sometimes rough and closely adherent, but usually flaking off in broad, thin, brittle scales, exposing the green or buff inner bark, which becomes nearly white on exposure; branchlets light brown, sometimes ridgy towards the ends, marked with numerous inconspicuous dots.
Winter Buds and Leaves.—Buds short, ovate, obtuse, enclosed in the swollen base of a petiole, and, after the fall of the leaf, encircled by the leaf-scar. Leaves simple, alternate, 5-6 inches long, 7-10 wide, pubescent on both sides when young, at maturity light rusty-green above, light green beneath, finally smooth, turning yellow in autumn, coriaceous; outline reniform; margin coarse-toothed or sinuate-lobed, the short lobes ending in a sharp point; base heart-shaped to nearly truncate; leafstalk 1-2 inches long, swollen at the base; stipules sheathing, often united, forming a sort of ruffle.
Inflorescence.—May. In crowded spherical heads; flowers of both kinds with insignificant calyx and corolla,—sterile heads from terminal or lateral buds of the preceding season, on short and pendulous stems; stamens few, usually 4, anthers 2-celled: fertile heads from shoots of the season, on long, slender stems, made up of closely compacted ovate ovaries with intermingled scales, ovaries surmounted by hairy one-sided recurved styles, with bright red stigmas.
Fruit.—In heads, mostly solitary, about 1 inch in diameter, persistent till spring: nutlets small, hairy, 1-seeded.