Salicaceae. 



Populus. Poplar. 

 (Family Salicaceae). 



Trees: deciduous. Bark at first 

 usually smooth and green or whit- 

 ish or orange, gray and often 

 deeply fissured in age. Wood rath- 

 er soft, white becoming brownish, 

 minutely diff used-porous with 

 fine medullary rays, satiny when 

 split. Twigs moderate, terete or 

 5-angled: pith rather small, 5-an- 

 gled, subcontinuous, brown. Buds 

 moderately small, ovoid or 

 elongated, appressed or sometimes 

 outcurved, sessile, solitary, with 

 several exposed scales of which 

 the lowermost is immediately over 

 the leaf-scar. Leaf-scars alter- 

 nate, somewhat raised, broadly 

 crescent - shaped to triangular, 

 somewhat 3-lobed, large: bundle- 

 traces 3, often compound: stipule- 

 scars narrow. 

 The poplars possess many winter differences besides those 

 3ed in the present key. The bark is differently roughened: 

 the native Cottonwood gray and grooved between flat-topped 

 idges, while in the commonly planted "Carolina cottonwood" 

 P. Eugenei), as in the Lombardy poplar which is one of 

 le parents of this, it is dark with pale fissures between rather 

 iarp ridges. On young trunks, and the branches of older 

 the smooth bark is colored in a characteristic fashion: 

 olive in the Lombardy poplar, orange in many "Carolina" 

 poplars, greenish-white in the large-toothed aspen, and some- 

 times almost chalky white in the silver poplar and our native 

 aspen. 



