LOCUST, a genus (Robinia) of legumi nous trees and shrubs. The species have odd pinnate leaves; pea-like flowers in drooping racemes, and pods containing several bean-like seeds. They are all useful for ornamental planting, and orie species, R. pseudacacia, is highly valued for Its timber. This species which is the best known, and is also called false acacia and black locust, is the largest of its genus, attaining heights exceeding 75 feet and girths greater than eight feet in the rich al luvial soils of Tennessee and Kentucky. Its hard, tough, close-grained yellow wood is espe cially useful for ship-building, fence-posts and other purposes in which great durability is re quired. It is also employed for making cog wheels, tree-nails, for the interior finish of houses, for furniture and other uses where a highly polished wood is needed. It is the favorite material for policemen's clubs, not only because of its weight and toughness, when well seasoned, but because of its unusual reso nance, giving a ringing report when struck upon the pavement as a signal which can be obtained from no other wood. In various parts of Europe great attention has been paid to the propagation of this tree, for ornament as well as for its useful properties, and its cultivation is further encouraged by the absence of the de stroying insects mentioned below. It forms a pleasing object along the borders of many of the railways on the Continent, its spines adding to its usefulness as Z hedge. When in bloom the large pendulous racemes of fragrant white flowers, contrasting with the light-green foliage, produce a fine effect and give this tree a rank among the most ornamental.
The chief objection to the tree is its liability to the attacks of insects, more than 40 species being known to feed upon its leaves and wood.
The foliage destroyers, which include leaf-roll ers, leaf-miners and several species that feed in exposed positions, are sometimes seriously destructive, the larvw of one species, a saw-fly (Nematis similaris), sometimes destroying all the green parts. But they are less destructive than the borers, which tunnel through and weaken the wood. Sometimes these are so numerous that the trees become mere shells of bark with a honeycomb of wood. The more important of them are the locust borer (CyIlene robinie), a black and yellow striped, long horned beetle in the adult stage, which is com mon in the eastern United States; and the larva of a moth (SciaPteron robinie), trouble some in the Pacific Coast region. These and some others have discouraged the commercial planting of this valuable tree.
Other American °locust* trees are the two species of the genus. Gleditsia of the senna family. These are the water or swamp locust (G. aquatica) of Florida, which has enormous spines and reddish flat oval pods; and the well known and widely-planted honey locust or honey shucks (G. triacanthos). This large, graceful but exceedingly thorny tree bears especially fragrant flowers, and its pods are gathered by country people in the South and eaten for the sake of the sweet pulp between the seeds. The great pods measure 10 to 20 inches long, are curved, and *in drying twist and retwist while they open, and skilfully scat ter seeds in diverse directions.*