A tree, sometimes 50°-60° high, with a trunk 1½°—2° or exceptionally 4° in diameter, usually divided 6°—7° from the ground into 2 or 3 stems, slender wide-spreading more or less pendulous brittle branches forming a wide graceful head, and zigzag branchlets clothed with pubescence when they first appear, soon becoming glabrous, during their first season light brown tinged more or less with green, very smooth and lustrous, and covered by numerous darker colored lenticels, bright red-brown in their first winter and marked by large elevated leaf-scars surrounding the buds, and dark dull brown the following year. Bark of the trunk ⅛′—¼′ thick, with a silvery gray or light brown surface and rather darker colored than that of the branches. Wood heavy, very hard, strong and close-grained, with a smooth satiny surface, bright clear yellow changing to light brown on exposure, with thin nearly white sapwood; used for fuel, occasionally for gun-stocks, and yielding a clear yellow dye.
Distribution. Limestone cliffs and ridges generally in rich soil, and often overhanging the banks of mountain streams; Cherokee County, North Carolina, and the western slopes of the high mountains of eastern Tennessee; central Tennessee and Kentucky; near Florence, Lauderdale County, and cliffs of the Warrior River, Tuscaloosa County, Alabama; Forsythe, Taney County, and Eagle Rock, Barry County, Missouri; rare and local; most abundant in the neighborhood of Nashville, Tennessee, and in Missouri.
Often planted in the eastern United States as an ornamental tree, and hardy as far north as New England; and rarely in western and southern Europe; usually only flowering in alternate years.
13. EYSENHARDTIA H. B. K.
Small glandular-punctate trees or shrubs, with slender terete branchlets. Leaves alternate, equally pinnate, petiolate; leaflets oblong, mucronate or emarginate at apex, short-petiolulate, numerous, stipellate; stipules subulate, caducous. Flowers short-pedicellate, in long spicate racemes, terminal or axillary, with subulate caducous bracts; calyx-tube campanulate, conspicuously glandular-punctate, 5-toothed, the acute teeth nearly equal, persistent; disk cupuliform, adnate to the base of the calyx-tube; corolla subpapilionaceous; petals erect, free, nearly equal, oblong-spatulate, rounded at apex, unguiculate, creamy white; standard concave, slightly broader than the wing and keel-petals; stamens 10, inserted with the petals, the superior stamen free, shorter than the others united to above the middle into a tube; anthers uniform, oblong; ovary subsessile, contracted into a long slender uncinate style geniculate and conspicuously glandular below the apex; stigma introrse, oblique; ovules 2 or 3, rarely 4, attached to the inner angle of the ovary, superposed. Legume small, oblong or linear-falcate, compressed, tipped with the remnants of the style, indehiscent, pendent. Seeds usually solitary, rarely 2, oblong-reniform, without albumen; seed-coat coriaceous; embryo filling the cavity of the seed; cotyledons flat, fleshy; radicle superior, short and erect.
Eysenhardtia is confined to the warmer parts of the New World, and is distributed from western Texas and southern New Mexico and Arizona to southern Mexico, Lower California, and Guatemala. Four species are distinguished; of these three species occur within the territory of the United States, and in northern Mexico, and one species is found only in Guatemala. Lignum nephriticum formerly celebrated in Europe for its reputed medical properties and for the fluorescence of its infusion in spring water is the wood of the shrubby Eysenhardtia polystachya Sarg. of western Texas and Mexico.
Of the North American species one is a small tree.
The generic name is in honor of Karl Wilhelm Eysenhardt (1794—1825), Professor of Botany in the University of Königsberg.
1. [Eysenhardtia orthocarpa] S. Wats.
