SALICACEAE 

 Black Cottonwood 



Populus trichocarpa Torr. & Gray 



HABIT. The largest of American poplars and the largest 

 broad-leaved tree in the Pacific Northwest; long, clear, cylin- 

 drical trunk; crown open, rounded. 



LEAVES. Ovate to ovate-lanceolate; 5-6 inches long and 

 3-4 inches wide; apex acute to long-acuminate; base rounded 

 or slightly cordate; margin finely crenate; leathery; dark green 

 above, silver-white to pale green below; petioles round, long. 



FRUIT. Capsules subglobose; Vs inch long; 3-valved; hairy. 



TWIGS. Moderately slender; round or slightly angled; 

 red-brown at first, becoming glabrous and dark gray. Winter 

 buds: terminal % inch long, ovoid, orange-brown, covered by 

 firagrant, yellow-brown resin. 



BARK. Smooth and greenish on young stems; becoming pale 

 gray, 1-2^ inches thick, deeply and sharply furrowed. 



* * * 

 Balsam Poplar 



Populus balsamifera L. {Populus tacamahacca Mill.) 



HABIT. A medium-sized tree seldom over 60-80 feet high 

 and 1-3 feet in diameter; open, narrow crown. 



LEAVES. Broadly ovate to ovate-lanceolate; 3-6 inches 

 long and 2-4 inches broad; apex acute to acuminate; base 

 rounded or cordate; finely crenate-serrate ; thin and firm; dark 

 green above, much paler below; petioles round, slender, long. 



FRUIT. Capsules ovoid; Vi-Vi inch long; 2-valved; glab- 

 rous; short-stalked. Seed: light brown, K2 inch long. 



TWIGS. Moderately stout; round; red-brown. Winter buds: 

 terminal 1 inch long, ovoid, chestnut-brown, saturated by 

 fragrant, amber-colored resin. 



BARK. On young trunks smooth and green-brown; on large 

 trunks deeply furrowed and gray-black. 



GENERAL The variety subcordata Hylander differs from 

 the species in having leaves which are usually broader, with 

 pubescent petioles. Balm-of-Gilead, a widely planted ornamental 

 tree in the Northeast, is a clon from a single pistillate tree of this 

 variety. 



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