EXOGENOUS SERIES— BROADLEAF PVOODS. lol 



Sour Gum, Black Gum, Tupelo. I^ssa sylvatka Marsh. 



Nomenclature. (Sudworth.) 



Sour Gum, Black Gum, Tu- Wild Pear Tree, Yellow Gum 



pelo (local and common Tree (Tenn. ). 



names). Gum (Md.). 



Pepperidge (Vt, Mass., R. I., Stinkwood (W. Va.), 



N. Y., N. J., S. C, Tenn., Tupelo Gum (Fla.). 



Mich., Ohio, Ontario). 



Locality. 



Maine to Florida, westward intermittently to Michigan and Texas. 



Features of Tree. 



Forty-five to one hundred feet high, one and six inches to occa- 

 sionally four feet in diameter. Ovoid, bluish-black, sour 

 fruit, with seed. Horizontal branches, short spur-like lateral 

 branchlets. 



Color, Appearance, or Grain of Wood. 



Heartwood light brown or yellow, often nearly white, sapwood 

 hardly distinguishable, fine grain. 



Structural Qualities of Wood. 



Heavy, not hard, fibres interlaced, therefore hard to work, 

 strong, tough, checks unless carefully seasoned, not durable 

 in contact with soil. 



Representative Uses of Wood. 



Wagon-hubs, rollers, ox-yokes, bowls, and woodenware. 



Weight of Seasoned Wood in Pounds per Cubic Foot. 



39- 

 Modulus of Elasticity. 



1, 160,000. 

 Modulus of Rupture. 



11,800. 



Remarks. 



Limited usefulness because difficult to work. Larger specimen 

 in South. Large trees often hollow at butts and sometimes 

 higher. 



