Distribution. Valley of the Yukon River to Saskatchewan, and southward through the mountain ranges of the Rocky Mountain region to southern New Mexico, the San Francisco Mountains of Arizona, and westward to the valley of the Skeena River, British Columbia, western Washington and Oregon, the western slopes of the Sierra Nevada and the high mountains of southern California, and eastward to North and South Dakota and western Nebraska; on the mountains of Chihuahua, and on the Sierra de Laguna, Lower California.
Populus tremuloides var. vancouveriana Sarg.
Populus vancouveriana Trel.
Leaves broadly ovate to semiorbicular, abruptly short-pointed or rounded at apex, rounded or slightly cordate at the broad base, coarsely crenately serrate and sometimes obscurely crispate on the margins, when they unfold covered below and on the petioles with a thick coat of long matted pale hairs, and slightly villose, glabrous or nearly glabrous above, soon glabrous, and at maturity thick dark green, lustrous and scabrate on the upper surface, paler on the lower surface, 3′—4½′ long and broad, with a prominent midrib and primary veins; petioles slender, compressed, becoming glabrous, 2′—3′ in length. Flowers: staminate aments slightly villose; pedicels pubescent; disk of the flower puberulous toward the base; flowers as in the species; pistillate aments 2′—2¼′ long, becoming 3′—3½′ in length at maturity; the rachis, pedicels and slightly lobed disk of the flower densely villose-pubescent; ovary conic, pubescent, with a short style and stigma divided into narrow divergent lobes. Fruit on pedicel not more than 1/24′ in length, oblong-conic, pubescent or glabrous, ¼′ long.
A tree 30°—36° high, with a trunk 12′—16′ in diameter, stout spreading branches forming a round-topped head, stout, reddish brown pubescent or puberulous branchlets often becoming glabrous during their first summer. Winter-buds acute, tomentose, pubescent or glabrous.
Coast of Vancouver Island, British Columbia and shores of Puget Sound; Tualitin, Washington County, and valley of the Willamette River at Corvallis, Benton County, Oregon.
2. [Populus grandidentata] Michex. Poplar.
Leaves semiorbicular to broad-ovate, short-pointed at apex, rounded, abruptly cuneate or rarely truncate at the broad entire base, coarsely repand-dentate above with few stout incurved teeth, covered like the petioles early in the season with white tomentum, soon glabrous, thin and firm in texture, dark green above, paler on the lower surface, 2′—3′ long, 2′—2½′ wide, with a prominent yellow midrib, conspicuously forked veins, and reticulate veinlets; petioles slender, laterally compressed, 1½′—2½′ long. Flowers: aments pubescent, 1½′—2½′ long, the pistillate becoming 4′—5′ long at maturity; scales pale and scarious below, divided above into 5 or 6 small irregular acute lobes covered with soft pale hairs; disk shallow, oblique, the staminate entire, the pistillate slightly crenate; stamens 6—12, with short slender filaments and light red anthers; ovary oblong-conic, bright green, puberulous, with a short style, and spreading stigmas divided nearly to the base into elongated filiform lobes. Fruit ripening before the leaves are fully grown, often more or less curved above the middle, light green and puberulous, thin-walled, 2-valved, about ⅛′ long; pedicel slender, pubescent, about 1/12′ in length; seeds minute dark brown.