﻿Trees of New York ISlate 129 



SALICACEAE 



Populus tremuloides Mielix. 



Trembling Aspen, American Aspen, Popple 



Habit — At maturity usually a small tree 30-60 feet in height with a trunk 

 diameter of 1-2 feet, under optimum conditions sometimes 100 feet tall. 

 Crown narrow, round-topped, open and irregular, consisting of slender, 

 somewhat ascending branches which often droop at the tip. Bole in large 

 trees with little taper until the crowai is reached, in smaller trees tapering 

 gradually into the crown. Propagates by root suckers. 



Leaves — Alternate, broadly ovate to orbicular, acute at the apex, rounded, 

 cordate or broadly cuneate at the base, finely serrate, lV^-3 inches in 

 diameter, when they first appear smooth, lustrous, pale green Avith ciliate 

 margins, at maturity thin, firm, smooth, dark green and lustrous above, 

 dull yellowish green and smooth below. 



Flowers — Appearing in late March and April before the leaves from separate 

 flower-buas, dioecious, borne in the axils of laciniately 3-5-lobed, hairy 

 scales, the whole forming cylindrical, hairy aments, l%-2i/^ inches long. 

 Perianth wanting. Stamens 6-12 with short, slender filaments and red- 

 dish anthers, inserted on an oblic^ue shallow disk. Pistil solitary, enlcosed 

 at the base in the tubular, slightly oblique disk, consisting of a conical, 

 green, puberulous ovary, a short style and 2 spreading, lobed stigmas. 



Fruit — A curved, pale green, thin-waJled capsule, about % of an inch long. 

 The capsules are borne rather loosely in naked, pedunculate aments 3— A 

 inches long, mature in May and June before the leaves have attained full 

 size, and open by opposite sutures to set free the minute, light brown, 

 white-comose seeds. 



Winder characters — Twigs rather slender, lentieellate, smooth and lustrous, 

 reddish brown, at length dark gray and roughened by the leaf- and lateral 

 branch-scars, ilower- and leaf-buds distinct. Leaf-buds conical and 

 somewhat curved, slightly resinous, acute, about % of an inch long, cov- 

 ered by 6-7 lustrous and glabrous, reddish browTi scales scaiious on the 

 margins. Flower-buds similar but larger, more obtuse and divergent. 

 Mature bark appearing rather tardily at the base of the old trees, nearly 

 black, thick, roughened by deep fissures and broad, flat ridges. Bark 

 higher on the bole and on the larger limbs thinner, smooth, yellowish 

 green to nearly white, roughened by areas of wart-like excrescences. 



Habitat — A " weed ' ' tree thriving on a variety of sites, swamps excepted, but 

 preferring rather dry, upland soils. Freciuent in slashes and burns, on 

 abandoned fields, limestone hills, etc. 



Range — A widely distributed transcontinental species extending from south- 

 ern Labrador through the Hudson Bay region to Alasaka, south in the 

 United States to northern I'ennsylvania, Kentucky and Missouri, and in 

 the west to Mexico and California. Zones B, C, and D. 



Uses — Wood light, soft, weak, close-grained, light brown with nearly white 

 sapwood. Largely used with Spruce and Fir in the manufacture of pulp. 

 Occasionally sawed into lumber and used for turnery, etc. Like the Large- 

 toothed Aspen, the tree is valuable as a cover tree, establishing itself 

 quickly in slashes and burns and protecting the soil until more valuable, 

 slower-growing species can dominate the terrain. 



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