SALICACEAE 



Narrowleaf Cottonwood 



Populus agustifolia James 



HABIT. A medium-sized tree 50-70 feet high and 12-20 

 inches in diameter; crown pyramidal with slender, erect branches. 



LEAVES. Lanceolate to ovate-lanceolate; 2-4 inches long 

 and ^-1^2 inches wide; apex long-tapering; finely to coarsely 

 serrate; thin and firm; bright yellow-green above, paler below; 

 petioles short (less than Vs length of blade), slender, somewhat 

 flattened on upper side. 



FRUIT. Capsules broadly ovoid; H inch long; 2-valved. 



TWIGS. Slender; round; yellow-green, becoming ash-gray. 

 Winter buds: terminal H-H inch long, slender, long-pointed, 

 chestnut-brown, very resinous and somewhat aromatic. 



BARK. Light yellow-green; H-1 inch thick; smooth except 

 near base of old trees where it is divided by shallow furrows. 



Lanceleaf Cottonw^ood 



Populus X acuminata Rydb. 



HABIT. A medium-sized tree about 40 feet high and 1-2 

 feet in diameter; rounded crown with large branches. 



LEAVES. Rhombic-lanceolate to ovate; 2-4 inches long 

 and M-2 inches wide; apex acuminate; base usually cuneate; 

 coarsely crenate-serrate ; rather thick; dark green above, dull 

 green below; petioles nearly round, slender, 1-3 inches long. 



FRUIT. Capsules oblong-ovoid; about Vs inch long; thin- 

 walled; acute; 3- or rarely 2-valved; on short, slender stalks. 



TWIGS. Slender; round or slightly 4-angled; pale yellow- 

 brown. Winter buds: terminal about V3-% inch long, narrow, 

 acuminate, light chestnut-brown, rather resinous. 



BARK. Nearly white and smooth on young trunks; on old 

 trees gray-brown, Yi inch thick, deeply divided into flat ridges. 



GENERAL. This tree is now generally regarded as a hybrid 

 between P. angustifolia and P. sargentii or P. fremontii. 



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