1. XANTHOXYLUM L.
Trees or shrubs, with acrid aromatic bark, pellucid aromatic-punctate fruit and foliage, scaly buds, and usually stipular spines. Leaves alternate, unequally or rarely equally pinnate; leaflets generally opposite, often oblique at the base, entire or crenulate. Flowers small, diœcious or polygamous, in axillary or terminal broad or contracted pedunculate cymes; calyx and petals hypogynous; disk small or obscure; stamens as many as the petals and alternate with them, hypogynous, effete, rudimentary or wanting in the female flower; filaments filiform or subulate; pistils 1—5, oblique, raised on the summit of a fleshy gynophore, connivent, sometimes slightly united below, rudimentary, simple or 2—5-parted in the sterile flower; ovaries 1-celled; styles short and slender, more or less united toward the summit; stigmas capitate; ovules collateral, pendulous from the inner angle of the cell. Fruit of 1—5 coriaceous or fleshy 1-seeded carpels, broad-obovoid, sessile or stipitate, ventrally dehiscent. Seed solitary oblong or globose, suspended on a slender funicle, often hanging from the carpel at maturity; seed-coat black, shining, conspicuously marked by the broad hilum; cotyledons oval or orbicular, foliaceous.
Xanthoxylum is widely distributed through tropical and extratropical regions and is most abundant in tropical America. It is represented in North America by one shrub and by four arborescent species of the southern states. The resin contained in the bark, especially in that of the roots, is a powerful stimulant and tonic occasionally used in medicine.
The generic name is from ξανθός and ξύλον.
CONSPECTUS OF THE ARBORESCENT SPECIES OF THE UNITED STATES.
Flowers in axillary contracted cymes; branches armed with stipular spines.1. [X. Fagara] (D, E). Flowers in terminal cymes. Calyx-lobes and petals 5; leaves unequally pinnate. Leaves deciduous; branches armed with stout spines.2. [X. clava-Herculis] (C). Leaves persistent; branches without spines.3. [X. flavum] (D). Calyx-lobes and petals 3; leaves equally pinnate, persistent.4. [X. coriaceum] (D).
1. [Xanthoxylum Fagara] Sarg. Wild Lime.
Fagara Fagara Small.
Leaves persistent, 3′—4′ long, with a broad-winged jointed petiole, and 7—9 obovate leaflets rounded or emarginate at apex, minutely crenulate-toothed above the middle, sessile, ½′ long or less, coriaceous, glandular-punctate, bright green and lustrous, with minute hooked deciduous stipular prickles. Flowers on short pedicels from the axils of minute ovate obtuse deciduous bracts, in short axillary contracted cymes, appearing singly or in pairs from April until June, on branches of the previous year, from minute dark brown globular buds, the staminate and pistillate flowers on different trees; sepals 4, membranaceous, much shorter than the 4 ovate yellow-green petals; stamens 4, with slender exserted filaments, 0 in the pistillate flower; pistils 2, with ovate sessile ovaries gradually contracted into long slender subulate exserted styles united near apex and crowned with obliquely spreading stigmas, rudimentary in the staminate flower. Fruit ripening in September, obovoid, rusty brown and rugose, ⅛′—¼′ long; seed dark and lustrous.
A tree, occasionally 25°—30° high, with a slender often inclining trunk, fastigiate branches, and more or less zigzag slender dark gray branchlets armed with sharp hooked stipular spines; more frequently a tall or low shrub. Bark of the trunk about ⅛′ thick, the smooth light gray surface broken into small appressed persistent scales. Wood heavy, hard, very close-grained, brown tinged with red, with thin yellow sapwood of 10—12 layers of annual growth.
Distribution. Coast and islands of southern Florida, and Texas from Matagorda Bay to the Rio Grande and in San Saba, Bandera, and Brown Counties; one of the commonest of the south Florida plants, and arborescent on the rich hummock soil of Elliott’s Key and the shores of Bay Biscayne; in Texas generally shrubby; common in northern Mexico, and widely distributed through the Antilles, southern Mexico, and Central and South America to Brazil and Peru.
2. [Xanthoxylum clava-Herculis] L. Prickly Ash. Toothache-tree.
Fagara clava-Herculis Small.
Leaves 5′—8′ long, with a stout pubescent or glabrous spiny petiole, and 3—9 pairs of ovate or ovate-lanceolate sometimes slightly falcate subcoriaceous leaflets usually oblique at base, crenulate-serrate, sessile or short-stalked, 1′—2½′ long, green and lustrous above, paler and often somewhat pubescent below, especially when they unfold; persistent until late in the winter or until the appearance of the new leaves in the early spring. Flowers on slender pedicels ⅓′—¼′ long, from the axils of minute lanceolate deciduous bracts, in ample wide-branched cymes 4′—5′ long and 2′—3′ wide, appearing in very early spring, when the leaves are about half grown, the staminate and pistillate flowers on different individuals; sepals minute, membranaceous, persistent, barely one fourth the length of the oval green petals ⅛′—¼′ long; stamens 5, with slender filiform filaments, conspicuously exserted from the male flowers, rudimentary or wanting in the female flowers; pistils 3, rarely 2, with sessile ovaries and short styles crowned by a slightly 2-lobed stigma. Fruit ripening in May and June, in dense often nearly globose clusters; mature carpels obliquely ovoid, 1-seeded, chestnut-brown, ¼′ long, with a rugose or pitted surface; seeds hanging at maturity outside the carpels.
A round-headed tree, 25°—30°, or exceptionally 50° high, with a short trunk 12′—18′ in diameter, numerous branches spreading nearly at right angles, and stout branchlets covered when they first appear with brown pubescence, becoming glabrous and light gray in their second year, and marked by small glandular spots and by large elevated obcordate leaf-scars displaying a row of large fibro-vascular bundle-scars, and armed with stout straight or sometimes slightly curved sharp chestnut-brown spines ½′ or more long, with a flattened enlarged base; or often a low shrub. Winter-buds short, obtuse, dark brown or nearly black. Bark of the trunk barely 1/16′ thick, light gray, and roughened by corky tubercles, with ovoid dilated bases sometimes 1′ or more across and thick and rounded at apex. Wood light, soft, close-grained, and light brown, with yellow sapwood. The bark, which is collected in large quantities by negroes in the southern states, is used as a cure for toothache and in the treatment of rheumatism.
Distribution. Southeastern Virginia southward near the coast to the shores of Bay Biscayne and Bocagrande, Lee County, Florida, and westward through the Gulf states to northern Louisiana, southern Arkansas (near Arkadelphia, Clark County), and eastern Oklahoma, and through Texas to the valley of the Colorado River ranging northward to Tarrant and Dallas Counties; in the Atlantic states not abundant, and confined to the immediate neighborhood of the coast, growing in light sandy soil and often on the low bluffs of islands or on river banks; from the Gulf coast ranging farther inland, especially west of the Mississippi River; most abundant in eastern Texas, and of its largest size on the rich intervale lands of the streams flowing into the Trinity River. In western Texas a form occurs (var. fruticosum Gray), with short sometimes 3-foliolate more or less pubescent leaves, with small ovate or oblong blunt and conspicuous crenulate rather coriaceous leaflets; this is the common form of western Texas, growing usually as a low shrub.
3. [Xanthoxylum flavum] Vahl. Satinwood.
Fagara flava Kr. & Urb.
Leaves unequally pinnate, persistent, usually 6′—9′ long, with a stout glandular petiole enlarged at base, and usually 5, sometimes 3, or rarely 1 leaflet, unfolding in Florida during the month of June, and then densely covered with tomentum, and at maturity sparingly hairy on the petiole and on the midrib of the ovate-lanceolate or elliptic, obtuse, often slightly falcate leaflets, sometimes oblique at base, nearly sessile or long-stalked, 2′—3′ long, 1½′—2′ broad, entire or slightly crenulate, coriaceous, pale yellow-green and conspicuously marked by large pellucid glands. Flowers appearing in Florida in June, on a slender pubescent pedicel ¼′ or more long, in wide-spreading pubescent sessile cymes, the male and female on different trees; calyx-lobes 5, minute, acuminate, ciliate on the margins, barely one eighth of the length of the ovate greenish white petals reflexed when the flowers are fully expanded; stamens 5, with slender filaments much longer than the petals, 0 in the pistillate flower; pistils 2 or sometimes 1, with a stipitate obovate ovary and a short style with a spreading entire stigma, minute and depressed in the staminate flower. Fruit ripening in autumn and early winter and sometimes persistent until the spring of the following year; mature carpels obliquely obovoid, short-stalked, 1-seeded, pale chestnut-brown at maturity, about ⅓′ long, faintly marked by minute glands.
A round-headed tree, 30°—35° high, with a trunk 12′—18′ in diameter, and stout brittle branchlets coated at first with thick silky pubescence, becoming light gray, rugose, conspicuously marked by large triangular leaf-scars, and puberulous during their second and third years. Winter-buds narrow-acuminate, ½′ long, coated with short thick pale tomentum. Bark of the trunk ¼′ thick, with a smooth light gray surface divided by shallow furrows and broken into numerous short appressed scales. Wood very heavy, exceedingly hard, brittle, not strong, light orange-colored, with thin rather lighter colored sapwood; occasionally used in southern Florida in the manufacture of furniture, for the handles of tools, and other objects of domestic use.
Distribution. Florida, on the Marquesas Keys and on South Bahia Honda and Boca Chica Keys; on Bermuda, the Bahama Islands, San Domingo, and Porto Rico.
4. [Xanthoxylum coriaceum] A. Richard.
Fagara coriacea Kr. & Urb.
Leaves equally pinnate, persistent, 2′—3′ long, with a stout grooved petiole, and 6—8 oblong-obovate stalked coriaceous dark yellow-green lustrous leaflets rounded or rarely emarginate at apex, 1′—1¾′ long and ⅝′—¾′ wide, with much-thickened revolute entire margins, a stout midrib, slender obscure spreading primary veins, and reticulate veinlets. Flowers yellow, appearing in March on short stout pedicels, in densely flowered terminal cymes; sepals 3, minute, united below, free above, much shorter than the 3 oval or obovate petals rounded at apex; stamens 3; filaments about as long as the petals; anthers ovoid or oval; ovary 3-celled, globose-ovoid; styles thick, 3 (teste Urban). Fruit: mature fruit not seen.
A glabrous tree, sometimes 18°—20° high, with a slender stem, and stout red-brown branches unarmed in Florida specimens, or in the West Indies furnished with short recurved spines; more often shrubby.
Distribution. Florida, shores of Bay Biscayne and near Fort Lauderdale, Dade County; rare; on the Bahama Islands and in Cuba.