The Poplars 



BB. Foliage pale, silvery or rusty below; margins finely 

 serrate. 

 C. Buds thickly covered with yellow resin. 



{P. halsamijera) balm of gilead 

 CC. Buds somewhat resinous. 

 D. Bark pale grey. 



(P. irichocarpa) black cottonwood 

 DD. Bark reddish brown. 



{P. heterophylla) swamp cottonwood 



Trees of the genus Populus form extensive , forests in low, 

 rich land and on high slopes of mountains. They attain large 

 size, are quick of growth, and have exceeding tenacity of life, 

 striking roots from twigs and sending up suckers from under- 

 ground. Seeds are also a reliable means of reproduction, as 

 they are produced in great numbers, and are widely scattered 

 by the wind. The wood is one of the best materials for pulp 

 making, and for a multitude of cheap wares for which a wood easy 

 to work is demanded. The trees are largely planted for shade and 

 ornament, for windbreaks, and to hold the banks of streams. 



There are twenty-five species of Populus known, eleven of 

 which are native to America. European species are often planted 

 in this country, where they usually thrive as if at home. Som.e 

 Russian varieties are successful on the Western prairies. China 

 and Japan each have representative poplars here. 



Cottonwood (Populus deltoidea, Marsh.) — Much-branched 

 tree, 60 to 150 feet in height; diameter 5 to 7^ feet. Bark deeply 

 furrowed, grey-brown, becoming greenish; often ashen grey 

 on old trees. Wood dark brown; sap wood white; weak, compact, 

 light. Buds large, pointed, resinous. Leaves broadly ovate, 

 taper pointed, 3 to 5 inches long, margin wavy and coarsely 

 toothed, thick, shining, paler beneath, yellow in fall; petiole 

 long, slender, flat, red or yellow. Flowers, March, in pendant 

 catkins, 3 to 5 inches long, loosely flowered; staminate red, 

 numerous; pistillate green, sparse on trees. Fruits, May, aments 

 6 to 12 inches long; capsules ovate, often curved, 2-valved; 

 seeds in white, cottony mass. Preferred habitat, moist soil along 

 streams. Distribution, Quebec to Northwest Territory; south to 

 Florida; west to Colorado and New Mexico. Uses: Much 

 planted for shade and windbreaks in the prairie states. Wood 

 has recently come into use in making packing cases. 



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