POPULUS MONOLIFERA COTTONWOOD. 39 



Fuel Value, 0.3611; Coefficient of Elasticity, 85690; Modulus of Rup- 

 ture, 550; Resistance to Longitudinal Pressure, 320; Resistance to In- 

 dentation, 75; Weight of a Cubic Foot in Pounds, 22.65. 



USES. Little use is made of this timber, so far as we are aware, ex- 

 cepting for paper pulp, for which it is excellent. 



MEDICINAL PROPERTIES. The virtues- of poplar buds are probably 

 analogous to those of the turpentines and balsams. They have been used 

 in pectoral, nephritic and rheumatic complaints in the form of tincture; 

 and a liniment made by macerating them in oil has been applied exter- 

 nally in rheumatism. It has been ascertained that poplar buds are 

 capable of imparting a principle to ointments which in a powerful 

 degree obviates their tendency to rancidity.* 



NOTE. Captain Franklin, in speaking of the Balsam Poplar, noted 

 that it constituted " the greater part of the drift timber that we ob- 

 served on the shores of the Arctic Sea/' This would indicate the prev- 

 alence of the timber in the far north. 



48. POPULUS MONOLIFERA, AIT. 



COTTON WOOD, NECKLACE POPLAR, WHITE WOOD, BIG COTTONWOOD. 

 Ger., RosenJcranz-Pappel : Fr., Peuplier ; Sp., Alamo de collar. 



SPECIFIC CHARACTERS. Leaves broadly deltoid or deltoid-ovate, smooth, but with 

 prominent veins, serrate-dentate with incurved, slightly hairy and cartilaginous teeth, 

 truncate or somewhat heart-shaped and nearly entire at base, taper-pointed, 2-4 inches 

 in length; length of petiole and length and width of blade about the same ; leaf-buds 

 varnished; branchlets angled, becoming terete. Flowers appear in April or May, the 

 fertile catkins recurved or pendulous and very long (4-8 inches) with capsules re- 

 mote: scales of catkin laciniate-fringed (not hairy); stigmas very large, nearly sessile 

 and toothed. 



(MonoLifera is from the Latin monolium, a necklace, and fero, 1 bear, in allusion to 

 the long, necklace-like fruiting catkins.) 



A large tree, attaining the height sometimes of 150 ft. (45 m.) and 6 

 or 7 ft. (2 m.) or more in diameter of trunk. The old trunks have a dark 

 and longitudinally furrowed bark. The large, varnished buds are a con- 

 spicuous feature when the leaves are off, and the tree presents a striking 

 appearance when in fruit on account of the long, fruiting catkins the 

 " necklaces " which it bears in abundance. Later every gust of wind, 

 for a time, bears away some of its delicate white cotton with appended 

 seeds. This "cotton" gives to the tree its popular name, Cottonwood, 

 and is a provision of nature for disseminating the seeds. 



HABITAT. From western New England southward to Florida and 

 westward to the Rocky Mountains, in moist soil along streams, lake 



*V. 8. Dispensatory, 10th ed., p. 1897. 



