EXOGENOUS SERIES— BROADLEAF PVOODS. 49 



Black Walnut. Juglans nigra Linn. 



Nomenclature. (Sudworth.) 



Black Walnut (local and common name). 



Walnut (N. Y., Del., W. Va., Fla., Ky., Mo., Ohio, Ind., la.). 



Locality. 



Ontario and Florida, westward intermittently to Nebraska and 

 Texas. 



Features of Tree. 



Ninety to one hundred and twenty-five feet in height, three to 

 eight feet in diameter. A tall handsome tree with rough 

 brownish, almost black, bark. Large, rough-shelled nuts. 



Color, Appearance, or Grain of Wood. 



Heartwood dark, rich, chocolate-brown. Thin sapwood much 

 lighter, rather coarse-grained. 



Structural Qualities of Wood. 



Heavy, hard, strong, easily worked, durable, susceptible to high 

 polish. 



Representative Uses of Wood. 



Cabinet-making, gun-stocks, also formerly furniture and decora- 

 tion. 



Weight of Seasoned Wood in Pounds per Cubic Foot. 



38. 

 Modulus of Elasticity. 



1,550,000. 

 Modulus of Rupture. 



12, 100. 

 Remarks. 



The English, Royal, or Persian Walnut {Juglans regid) affords 

 nearly similar wood. Widely distributed over Europe. Italian trees 

 furnish best, French next, and English least desirable, paler and 

 coarser wood. Occasional trees in Eastern United States, as New 

 York; very plentiful in California. 



