Distribution. Shores of Matagorda Bay to Hidalgo and Valverde Counties, Texas, and in northern Mexico; not common in Texas; very abundant and a conspicuous feature of vegetation in Mexico from the mouth of the Rio Grande to the foothills of the Sierra Madre.
2. [Cercidium Torreyanum] Sarg. Green-barked Acacia. Palo Verde.
Leaves few and scattered, 1′ long, hoary-tomentose when they first appear, puberulous at maturity, with a slender petiole and 2 pinnæ, with 2 or 3 pairs of oblong obtuse glaucous leaflets narrowed toward the somewhat oblique base, 1/12′—⅙′ long; unfolding in March and April and falling almost immediately when fully grown. Flowers ¾′ in diameter, on slender pedicels ¾′—1′ long, in 4 or 5-flowered racemes about 1′ in length, with small acute membranaceous caducous bracts. Fruit ripening and falling in July, 3′—4′ long, ¼′—⅓′ wide, 2—8-seeded, slightly turgid, often somewhat contracted between the seeds, frequently grooved on the ventral suture; seeds turgid, ⅓′ long.
A low intricately branched tree, leafless for most of the year, 25°—30° high, with a short often inclining trunk 18′—20′ in diameter, stout spreading branches covered with yellow or olive-green bark, forming a wide open irregular head, and glabrous slightly zigzag light yellow or pale olive-green and glaucous branchlets armed with thin straight or curved spines ¼′ long. Bark thin, smooth, pale olive-green, becoming near the base of old trunks reddish brown, ⅛′ thick, furrowed and separating into thick plate-like scales. Wood heavy, not strong, soft, close-grained, light brown, with clear light yellow sapwood.
Distribution. Sides of low cañons and depressions, and sandhills of the desert; valley of the lower Gila River, Arizona, to the Colorado Desert of southern California, and southward into Sonora and Lower California; when in flower in early spring the conspicuous and most beautiful feature of the vegetation of the Colorado Desert.
11. SOPHORA L.
Trees or shrubs, with minute scaly buds, unarmed terete branches prolonged by an upper axillary bud, and fibrous roots. Leaves unequally pinnate, with numerous small or few and ample thin or coriaceous leaflets; stipules minute, deciduous; stipels often 0. Flowers in terminal or axillary racemes, with linear minute deciduous bracts and bractlets; calyx broad-campanulate, often slightly turbinate or obconic at base, obliquely truncate, the short teeth nearly equal or the 2 upper subconnate and often somewhat larger than the others; disk cupuliform, glandular, adnate to the calyx-tube; corolla papilionaceous; petals white or violet blue, unguiculate; standard obovate or orbicular, usually shorter than the oblong, suberect keel-petals, as long or rather longer than the oblong-oblique wings, overlapping each other at the back, barely united; stamens free, or 9 of them slightly united at base, uniform; anthers attached on the back near the middle; ovary short-stipitate, contracted into an incurved style, with a minute truncate or slightly rounded capitate stigma; ovules numerous, suspended from the inner angle of the ovary, superposed, amphitropous. Legume terete, much contracted between the seeds, woody or fleshy, usually many-seeded, each seed inclosed in a separate cell, indehiscent. Seed oblong or oval, sometimes somewhat compressed; seed-coat thick, membranaceous or crustaceous; cotyledons thick and fleshy; radicle short and straight or more or less elongated and incurved.
Sophora is scattered over the warmer parts of the two hemispheres, with about twenty species of trees, shrubs or herbs; of the six North American species two are small trees. Several of the species produce valuable wood, and from the pods and flower-buds of the Chinese Sophora japonica L., a dye is obtained used to dye white cloth yellow and blue cloth green. This tree is often cultivated as an ornament of parks and gardens in northern China, Japan, the eastern United States, and in western, central, and southern Europe.
The generic name is from Sophera, the Arabic name of some tree with pea-shaped flowers.