EXOGENOUS SERIES BROADLEAF WOODS. 89 



Poplar, Largetooth Aspen. Populus grandidentata Michx. 



Nomenclature. (Sudworth.) 



Poplar, Largetooth Aspen White Poplar (Mass.). 



(local and common names). Popple (Me.). 

 Largetooth Poplar (N. C. ). Large American Aspen (Ala. ). 



Large Poplar (Tenn.). 



Locality. 



Nova Scotia and Delaware, westward intermittently to Minne- 

 sota, Alleghany Mountains to Kentucky and Tennessee. 



Features of Tree. 



Sixty to eighty feet high, two feet or more in diameter. Irreg- 

 ular points or teeth on margins of leaves. Smooth gray bark. 



Color, Appearance, or Grain of Wood. 



Heartwood brownish, sap wood nearly white, close-grained, 

 compact structure. 



Structural Qualities of Wood. 

 Soft, light, weak. 



Representative Uses of Wood. 



Paper-pulp and occasionally woodenware. 



Weight of Seasoned Wood in Pounds per Cubic Foot. 



28. 

 Modulus of Elasticity. 



1,360,000. 

 Modulus of Rupture. 



10,200. 



Remarks. 



The several " poplars " are much prized for paper-pulp. The 

 quaking aspen (P. tremuloides) has long leaf-stalks flattened 

 vertically to the leaf-surface, so that leaves tremble in slight 

 winds, a characteristic peculiar throughout of the genus 

 Populus. 



Ailanthus (Ailanthus glandulosa). This sturdy, beautiful, very quick- 

 growing, but short-lived tree was once popular in this country, particularly in 

 city landscapes, but it was discarded because of the disagreeable, far reaching 

 odor of its flowers. The tree has many merits and an odorless variety is 

 fortunately available. The wood is used for wooden ware and charcoal in Europe 

 and in China where certain silk worms feed upon the leaves. The Chinese call 

 the Ailanthus the "tree of Heaven." American specimens have grown in excess 

 of ten feet in length during the first year. _, 



