EXOGENOUS SERIES—BROADLEAF IVOODS. 37 



Cork Elm. Ulmus racemosa Thomas. 



Nomenclature. (Sudworth.) 



Cork Elm (local and common Rock Elm (R. I. , W. Va. , Ky. , 

 name). Mo., 111., Wis., la., Mich., 



Hickory Elm (Mo., 111., Ind., Nebr.). 



la.). White Elm (Ont.). 



Cliff Elm (Wis.). 



Locality. 



Quebec and Vermont, westward intermittently to Nebraska and 

 Tennessee. Best developed in southern Ontario and 

 Michigan. 



Features of Tree. 



Seventy to ninety feet in height, two to three feet in diameter. 

 Thick, corky, irregular projections give bark a shaggy appear- 

 ance and mark the species. 



Color, Appearance, or Grain of Wood. 



Heartwood light brown, often tinged with red; sapwood 

 yellowish or greenish white. Compact structure, fibres inter- 

 laced. 



Structural Qualities of Wood. 



Heavy, hard, very strong, tough, difficult to split, susceptible 

 of a beautiful polish, elastic. 



Representative Uses of Wood. 



Heavy agricultural implements, wheel-stocks, railway ties, sills, 

 bridge-timbers, axe-helves, etc. 



Weight of Seasoned Wood in Pounds per Cubic Foot. 



45- 

 Modulus of Elasticity. 



2,550,000. 

 Modulus of Rupture. 



15,100. 



Remarks. 



Cork Elm is the best of the elm woods. 



