The wood of the honey locust resembles that of the black locust, but is seldom used or appreciated save for fencing and similarly unimportant purposes. Trees grow rapidly and are not subject to the attacks of insects, so that they frequently attain to normal proportions. The flowers are much smaller than those of the black locust, but the pods are several times as long (twelve to eighteen inches). These often curl in drying and are thus rolled to some distance by the wind. Thorns or spines are present on some individuals and are often from three to six inches in length. The foliage resembles but is more delicate than that of the black locust. There is at least one other American species. _Gleditsia_ is from Gleditsch, the name of a botanist. Mesquite, also called honey locust, affords wood that is hard, heavy, and almost indestructible in exposed positions. The tree grows in the desert where vegetation would often seem to be impossible. The roots are developed to great size by their search for water, and are gathered and burned in the absence of other fuel. The trunks are small, but afford posts and ties. There are pods filled with rich edible pulp. Sixteen or more species belong to this genus, prosopis, of which one other, the screw-pod mesquite (_Prosopis odorata_), is found in the United States. [p077] FOOTNOTES [Footnote 45: Three of the four United States species are trees; the other species of this genus grow in Mexico. No one is approximately as important or well known as the Black Locust.] [Footnote 46: Black Locust was introduced into Europe early in the seventeenth century, being first cultivated by the son of Jean Robin, for whom the genus is named. Few American species have received such attention abroad.] LOCUST, BLACK LOCUST, YELLOW LOCUST. _Robinia pseudacacia Linn._ Nomenclature. (Sudworth.) Locust, Black Locust, Yellow Locust (local and common names). False Acacia (S. C., Ala., Tex., Minn.). Pea-flower Locust, Post Locust (Md.). Red Locust, Green Locust (Tenn.). Honey Locust (Minn.). White Locust (R. I., N. Y., Tenn.). Acacia (La.). 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, construction, turnery, ship-ribs, ornamentations, fuel. Weight of Seasoned Wood in Pounds per Cubic Foot. 45. Modulus of Elasticity. 1,830,000. Modulus of Rupture. 18,100. Remarks.