SALICACEAE 

 Aspen 



Populus tremuloides, Mich.v. 



HABIT. A small, slender tree generally 35-45 feet high, 

 with a trunk diameter of 8-15 inches; forming a loose, rounded 

 crown of slender branches. 



LEAVES. 'Alternate, simple, i l / 2 -2 l A inches long and broad; 

 broadly ovate to suborbicular ; finely serrate; thin and firm; 

 lustrous, dark green above, dull and pale beneath ; petioles slender, 

 laterally compressed. Tremulous with the slightest breeze. 



FLOWERS. .April, 'before the leaves; dioecious; the stam- 

 inate catkins 1^2-3 inches long, the pistillate at first about the 

 same length, gradually elongating; calyx o; corolla o; stamens 

 6-12; stigmas 2, 2-lobed, red. 



FRUIT. May-June ; 2-valved, oblong-cylindrical, short- 

 pedicelled capsules *4 inch long; seeds light brown, white-hairy. 



WINTER-BUDS. Terminal bud about Y 4 inch long, nar- 

 row-conical, acute, red-brown, lustrous ; lateral buds often 

 appressed. 



BARK. Twigs very lustrous, red-brown, becoming grayish 

 and roughened toy the elevated leaf-scars; thin, yellowish or 

 greenish and smooth on the trunk, often roughened with darker, 

 horizontal bands or wart-like excrescences, becoming thick and 

 fissured, almost black at the base of old trunks. 



WOOD. Light, soft, weak, close-grained, not durable, light 

 brown, 'with thin, whitish sapwood. 



DISTRIBUTION. Common throughout the state, but most 

 abundant in the Upper Peninsula. 



HABITAT. Prefers moist, sandy soil and gravelly hill- 

 sides. 



NOTES. One of the first trees to cover burned-over lands. 

 Grows rapidly. Usually short-lived. Propagated from seed or 

 cuttings. 



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