BALSAM POPLARS. 193 



inches in length; stamens very numerous, purple. Seeds with 

 a large cottony float. A large, upright tree with narrow 

 straight top, and nearly smooth gray bark, the largest of the 

 sub-arctic trees. 



Distribution. Over the low bottom lands and swamp 

 borders of the greater part of British America and the 

 northern part of the United States. In Minnesota found 

 throughout the northern part of the state. 



Propagation. By seeds and cuttings. 



Properties of wood. Light, soft, not strong, close grained; 

 light brown with thick nearly white sapwood. Specific grav- 

 ity 0.3635; weight of a cubic foot 22.65 pounds. 



Uses. The Balsam Poplar and its varieties are occasion- 

 ally used for ornamental planting, but while they are of rapid 

 growth and occasionally make good specimens, their open 

 habit and liability to die in the top make them undesirable for 

 extensive planting. The wood is excellent for paper pulp. 

 The buds are used in liniments; their virtues probably being 

 analagous to those of turpentine and the balsams. 



Varieties. 



Populus balsamifera candicans. Balm of Gilead. 



This form has a wider leaf, longer and more resinous 

 buds, more spreading branches, heavier wood, and is a more 

 ornamental tree than the species. It is common in plantings 

 in the northeastern states and eastern Canada. 



Populus balsamifera intermedia. 



A European form with close, upright habit, and very 

 thick hard oval leaves which are whitened beneath. It is 

 known to horticulturists as P. laurifolia and P. siberica pyra- 

 midalis. 



Populus balsamifera viminalis. 



A native of northern Europe. The tree is of slender 

 growth with a slightly weeping habit when old; it has sharply 

 angled twigs and willow-like leaves. Known to horticultur- 

 ists as P. lindleyana, P. salicifolia, P. crispa, P. dudkyi and 

 P. pyramidalis suaveolens. 



Populus balsamifera latifolia. 

 A variety including several Asiatic forms with ovate 



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