EXOGENOUS SERIES BROADLEAF WOODS. 77 



Locust, Black Locust, Yellow Locust. Robinia pseudacacia Linn. 



Nomenclature. (Sudworth. ) 



Locust, Black Locust, Yel- Red Locust, Green Locust 



low Locust (local and (Tenn.). 



common names). Honey Locust (Minn.). 



FalseAcacia (S. C , Ala., Tex., White Locust (R. I., N. Y., 



Minn.). Tenn.). 



Pea-flower Locust, Post Lo- Acacia (La.). 



cust (Md.). 



Locality. 



Southern Alleghany region, widely cultivated in United States 

 east of Rocky Mountains. 



Features of Tree. 



Fifty to seventy feet in height, two to three feet or over in 

 diameter. Leaves curl or close at night. Long spikes or 

 briers on young branches. 



Color, Appearance, or Grain of Wood. 



Heartwood brownish, thin sapwood, light-greenish yellow. 

 Close-grained and compact. Annual layers clearly marked. 



Structural Qualities of Wood. 



Heavy, very hard, strong, and durable under extreme conditions 

 of wet and dry. 



Representative Uses of Wood. 



Long wooden bolts or pins called treenails. Posts, ties, con- 

 struction, turnery, ship-ribs, ornamentations, fuel. 



Weight of Seasoned Wood in Pounds per Cubic Foot. 



45- 

 Modulus of Elasticity. 



1,830,000. 

 Modulus of Rupture. 



1 8, 100. 



Remarks. 



Often a low shrub. Extensively planted, particularly in West, 

 but subject to attack by borers. One of the most valuable 

 of American timber trees. Heartwood is formed very early 

 in this species. Pseudacacia means false acacia or imitation 

 of acacia. 



