Part 94

A tree, occasionally 25°—30° high, with a trunk 6′—8′ in diameter, dividing at some distance from the ground into a number of small upright branches, and branchlets light orange-brown and covered during their first season with short fine pubescence, and pale brown tinged with red, glabrous and marked by scattered lenticels in their second year; more often a shrub, with numerous stems. Winter-buds about ⅛′ in diameter. Bark of the trunk rarely more than ¼′ thick, light gray and broken by numerous shallow reticulated fissures. Wood heavy, close-grained, rather soft and brittle, red tinged with brown, with lighter colored sapwood. The sweet seeds possess powerful emetic properties and are reputed to be poisonous.

Distribution. Borders of streams, river-bottoms and limestone hills, and westward on the sides of mountain cañons; valley of the Trinity River, Dallas County and of the lower Brazos River, Texas, to the mountains of southeastern New Mexico, and southward into Mexico; most common and of its largest size forty to fifty miles from the Texas coast west of the Colorado River.

Occasionally cultivated as an ornamental plant in the southern United States.

XXXVIII. RHAMNACEÆ.

Trees or shrubs, with scaly or naked buds, watery bitter astringent juice, simple leaves, and minute deciduous stipules (_persistent in Krugiodendron_). Flowers small, mostly greenish, perfect (_polygamo-diœcious in one species of Rhamnus_); calyx 4—5-lobed, the lobes valvate in the bud; petals 4—5, inserted on the calyx near the margin of the conspicuous disk lining the short calyx-tube, and infolding the stamens, or 0; stamens as many as and alternate with the calyx-lobes, free, inserted at or below the margins of the disk; filaments slender, subulate; anthers introrse, versatile, 2-celled, the cells opening longitudinally; pistils of 2—3 united carpels; ovary 2—3-, or rarely 1-celled by abortion, partly immersed in the disk; style terminal; stigma 2—4-lobed; ovules 1 in each cell, erect, anatropous; raphe ventral; micropyle inferior. Fruit drupaceous, supported on the tube of the calyx and bearing the remnants of the style. Seed usually with scanty oily albumen; embryo with broad cotyledons; radicle inferior, next the hilum.

CONSPECTUS OF THE ARBORESCENT GENERA OF THE UNITED STATES.

Fruit more or less fleshy. Fruit with a single stone; petals 0. Sepals without crests. Leaves alternate; branches spinescent. 1. Condalia. Leaves nearly opposite; branches not spinescent. 2. Reynosia. Sepals crested; leaves mostly opposite. 3. Krugiodendron. Fruit with 2 or 3 nutlets; petals 4 or 5, or 0; leaves alternate. 4. Rhamnus. Fruit crustaceous, 3-lobed, separating into 3 longitudinally 2-valved nutlets. Sepals inflexed; petals narrowed into a long slender claw. 5. Ceanothus. Sepals spreading; petals sessile. 6. Colubrina.

1. CONDALIA Cav.

Trees or shrubs, with rigid spinescent branches and minute scaly buds. Leaves alternate, subsessile, obovate or oblong, entire, feather-veined. Flowers axillary, solitary or fascicled, greenish white, on short pedicels; calyx with a short broad-obconic tube and a 5-lobed limb, the lobes ovate, acute, membranaceous, spreading and persistent; disk fleshy, flat, slightly 5-angled, surrounding the free base of the ovary; petals 0; stamens 5, inserted on the free margin of the disk between the lobes of the calyx; filaments incurved, shorter than the calyx-lobes; ovary 1-celled, conic, gradually narrowed into a short thick style; stigma 3-lobed; ovule ascending from the base of the cell. Fruit ovoid or subglobose; flesh thin; stone thick-walled, crustaceous. Seed compressed; seed-coat thin and smooth; cotyledons oval, flat.

Condalia with nine or ten species is confined to the New World and is distributed from western Texas and southern California to Brazil and Argentina. Of the six species found within the territory of the United States one is a small tree.

The generic name commemorates that of Antonio Condal, a Spanish physician of the eighteenth century sent to South America on a scientific mission in 1754.

1. Condalia obovata Hook. Purple Haw. Log Wood.

Leaves often fascicled on short spinescent lateral branchlets, spatulate to oblong-cuneate, mucronate, when they first appear pubescent, especially on the lower surface, at maturity glabrous, rather thin, pale yellow-green, 1′—1½′ long, and about ⅓′ wide, with a conspicuous midrib and usually 3 pairs of prominent primary veins; unfolding in May and June and falling irregularly during the winter. Flowers in 2—4-flowered short-stemmed fascicles, on branchlets of the year. Fruit ripening irregularly during the summer, ¼′ long, dark blue or black, with a sweet pleasant flavor.

A tree, sometimes 30° high, with a trunk 6′—8′ in diameter, erect rigid zigzag branchlets terminating in a stout spine and covered at first with soft velvety pubescence, becoming glabrous before the end of their first season, pale red-brown and often covered with thin scales; more often a shrub. Bark of the trunk about ⅛′ thick, divided into flat shallow ridges, the dark brown surface tinged with red separating into thin scales. Wood very heavy, hard, close-grained, light red, with light yellow sapwood of 7—8 layers of annual growth; burning with an intense heat and valued as fuel.

Distribution. Southwestern Texas from Jackson County (Vanderbilt) and Corpus Christi, Nueces County, to the Rio Grande and to Comal and Valverde Counties; in northeastern Mexico; of tree-like habit and of its largest size on the high sandy banks of the lower Rio Grande and its tributaries; often covering large areas with dense impenetrable chaparral.

2. REYNOSIA Griseb.

Trees or shrubs, with rigid unarmed terete branches, and scaly buds. Leaves mostly opposite, entire, coriaceous, short-petiolate, reticulate-veined, persistent. Flowers minute, on stout pedicels bibracteolate near the base and two or three times longer than the flower, in small axillary sessile umbels; calyx persistent, 5-lobed, the lobes deltoid or ovate, acute or acuminate, spreading, petaloid, deciduous; disk fleshy; petals 0; stamens 5, inserted on the margin of the disk, rather shorter than the calyx-lobes; filaments incurved; anthers oval; ovary free from the disk, almost superior, conic, 2—3-celled, contracted into a short erect thick style; stigma 2—3-lobed. Fruit drupaceous; flesh thin; stone crustaceo-membranaceous. Seed ovoid or subglobose; seed-coat very thin, conspicuously rugose and tuberculate; embryo axile in copious subcorneous ruminate albumen; cotyledons oblong.

Reynosia is distributed from southern Florida and the Bahama Islands to the Antilles. Four species are recognized; of these, one, a small tree, extends into southern Florida.

The generic name is in honor of Alvaro Reynoso (1830—1888), the distinguished Cuban chemist and writer on agriculture and scientific subjects.

1. Reynosia septentrionalis Urb. Red Ironwood. Darling Plum.

Leaves oblong to ovate or obovate, or sometimes nearly orbicular, rounded, truncate or frequently emarginate and usually minutely apiculate at apex, gradually narrowed at base into a short broad petiole, very thick and coriaceous, dark green on the upper, rather paler or often rufous on the lower surface, 1′—1½′ long and ½′ broad, with thickened revolute margins, a stout broad midrib, about five pairs of primary veins spreading nearly at right angles, and numerous reticulate veinlets; unfolding in April and remaining on the branches for one and sometimes for two years. Flowers yellowish green appearing in May, 1/12′ long; sepals ovate, acute. Fruit ripening in Florida in November or frequently not until the following spring, short-obovoid, ½′ long, purple or nearly black, edible, with an agreeable flavor.

A tree, 20°—25° high, with a trunk 6′—8′ in diameter, stout terete rigid branchlets slightly puberulous when they first appear, soon becoming glabrous and gray faintly tinged with red, growing darker in their second season, then often covered by small tubercles and marked by the prominent elevated leaf-scars. Winter-buds minute, chestnut-brown. Bark of the trunk 1/16′—⅛′ thick, dark-red-brown, and divided into large plate-like scales. Wood heavy, exceedingly hard, strong, close-grained, rich dark brown, with light brown sapwood of 15—20 layers of annual growth.

Distribution. Florida, coast and islands from the Marquesas group to the shores of Bay Biscayne and the Everglade Keys, Dade County; common and generally distributed; on the Bahama Islands.

3. KRUGIODENDRON Urb.

A small tree or shrub, with slender unarmed terete branches roughened by numerous small lenticels, and minute scaly buds. Leaves opposite or obliquely opposite, or sometimes alternate on lower branches, ovate or oval, often emarginate, coriaceous, entire, short-petiolate, feather-veined, persistent; stipules acuminate, persistent. Flowers greenish yellow, on short slender pedicels, in axillary simple or dichotomously branched cymes; calyx broad-obconic, 5-lobed, the lobes triangular, acute, erect or spreading, conspicuously crested on the inner surface, deciduous; disk annular, broad, fleshy, 5-lobed, surrounding the base of the ovary; petals 0; stamens 5, inserted under the margin of the disk; anthers ovoid or ovoid-orbicular, obtuse; ovary conic, imperfectly 2-celled; styles short and thick, united nearly to the apex, the branches spreading and stigmatic on the inner face; ovule ascending from the base of the cell. Fruit 1-seeded, oval or ovoid; flesh thin and black; wall of the stone thin and bony. Seed ellipsoid, compressed, without albumen; seed-coat membranaceous; embryo filling the cavity of the seed; cotyledons thick and fleshy, obovate or elliptic.

Krugiodendron, with a single species, is confined to southern Florida and the West Indies.

The generic name is in honor of Leopold Krug (1833—1898), a student of the flora of the Antilles.

1. Krugiodendron ferreum Urb. Black Ironwood.

Leaves bright green and lustrous above, pale yellow-green below, glabrous with the exception of a few scattered hairs on the upper surface and on the petiole, 1′—1½′ long and ¾′—1′ wide, with entire or slightly undulate margins; persistent for two or three years; petioles stout, ¼′ in length. Flowers on bibracteolate pedicels ¼′ long, in 3—5-flowered cymes on peduncles sometimes ½′ in length, usually much shorter and often branched near the apex, on branchlets of the year; calyx about 1/16′ long. Fruit generally solitary, ⅓′ in length, on a stem ⅓′—½′ long.

A tree, sometimes 30° high, with a trunk 8′—10′ in diameter, and slender branchlets at first green and covered with dense velvety pubescence, becoming glabrous in their second year, and then gray faintly tinged with red and roughened by small crowded lenticels; generally much smaller and more often shrubby than arborescent. Bark of the trunk about ¼′ thick and divided into prominent rounded longitudinal ridges broken on the surface into short thick light gray scales. Wood exceedingly heavy, hard, strong, close-grained, brittle, rich orange-brown, with thin lighter colored sapwood.

Distribution. Florida, Cape Canaveral on the east coast to the shores of Bay Biscayne and on the Everglade Keys, Dade County, near Cape Sable, and on the southern keys; one of the commonest of the small trees of the region; on the Bahama Islands and on several of the Antilles.

4. RHAMNUS L.

Trees or shrubs, with terete often spinescent branches, without a terminal bud, scaly or naked axillary buds and acrid bitter bark. Leaves alternate or rarely obliquely opposite, conduplicate in the bud, petiolate, feather-veined, entire or dentate, stipulate. Flowers perfect or polygamo-diœcious, in axillary simple or compound racemes or fascicled cymes; calyx campanulate, 4—5-lobed, the lobes triangular-ovate, erect or spreading, keeled on the inner surface, deciduous; disk thin below, more or less thickened above; petals 5, inserted on the margin of the disk, ovate, unguiculate, emarginate, infolded round the stamens, deciduous, or 0; stamens 4 or 5; filaments very short; anthers oblong-ovoid or sagittate, rudimentary and sterile in the pistillate flower; ovary free, ovoid, included in the tube of the calyx, 2—4-celled, rudimentary in the staminate flower; styles united below, with spreading stigmatic lobes or terminating in a 2—3-lobed obtuse stigma; ovule erect from the base of the cell. Fruit drupaceous, oblong or spherical; flesh thick and succulent, inclosing 2—4 separable cartilaginous 1-seeded nutlets. Seeds erect, obovoid, grooved longitudinally on the back, with a cartilaginous seed-coat, the raphe in the groove, or convex on the back, with a membranaceous seed-coat, the raphe lateral next to one margin of the cotyledons; embryo large, surrounded by thin fleshy albumen; cotyledons oval, foliaceous, with revolute margins, or flat and fleshy.

Rhamnus with about sixty species is widely distributed in nearly all the temperate and in many of the tropical parts of the world with the exception of Australasia and the islands of the Pacific Ocean. Of the five species indigenous to the United States three attain the size of small trees. The fruit and bark of Rhamnus are drastic, and yield yellow and green dyes. The European _Rhamnus cathartica_ L., the Buckthorn, has long been used as a hedge plant in northern Europe, and in eastern North America, where it has now become sparingly naturalized.

The generic name is from ῥάµνος, the classical name of the Buckthorn.

CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.

Flowers polygamo-diœcious, in sessile umbels; calyx 4-lobed; petals 0; anthers oblong-ovoid; lobes of the stigma elongated, spreading; fruit red; seed grooved on the back; seed-coat cartilaginous; leaves often sharply toothed, persistent; winter-buds scaly. 1. R. crocea (G). Flowers perfect, in pedunculate umbels; calyx 5-lobed; petals 5; anthers sagittate; lobes of the stigma short and obtuse; fruit black; seed rounded on the back; seed-coat membranaceous; leaves deciduous; winter-buds naked. Peduncles shorter than the petioles. 2. R. caroliniana (C). Peduncles longer than the petioles. 3. R. Purshiana (B, G).

1. Rhamnus crocea Nutt.

Leaves persistent, often in fascicles, elliptic, broad-ovate to suborbicular, rounded and often apiculate at apex, glandular-denticulate with minute teeth, coriaceous, yellow-green and lustrous on the upper surface, pale and frequently bronzed or copper color on the lower surface, glabrous or often puberulous while young, with a prominent midrib and slender primary veins, ¼′—¾′ long; petioles short and stout; stipules minute, acuminate. Flowers polygamo-diœcious, on slender often puberulous pedicels, in small clusters from the axils of the leaves or of small lanceolate persistent bracts on shoots of the year; calyx 4-lobed, with acuminate lobes, about ⅛′ long; petals 0; stamens rather shorter than the calyx, with short stout incurved filaments and large ovoid anthers, minute and rudimentary in the pistillate flower; ovary ovoid, contracted into a long slender style divided above the middle into two wide-spreading acuminate stigmatic lobes, rudimentary in the staminate flower. Fruit red, obovoid, slightly grooved or lobed at maturity, ¼′ long, with thin dry flesh and 1—3 nutlets; seed broad-ovoid, pointed at apex, deeply grooved on the back and ⅛′ long, with a thin membranaceous pale chestnut-colored coat.

A shrub, 6′—3° high, with slender rigid often spinescent branchlets forming thickets.

Distribution. Coast mountains of central and southern California. Passing into

Rhamnus crocea var. ilicifolia Greene.

Leaves oval or orbicular, spinulose-dentate, often golden beneath and 1′—1½′ long and ¾′—1′ wide. Flowers with 4 or occasionally 5 calyx-lobes and stamens.

A tree, occasionally 25° high, with a trunk 6′—8′ in diameter, stout spreading branches, and slender branchlets yellow-green and puberulous or glabrate when they first appear, becoming dark red or reddish brown and glabrous in their second season. Winter-buds obtuse, barely more than 1/16′ long, with small puberulous apiculate imbricated scales ciliate on the margins. Bark of the trunk usually from 1/16′—⅛′ thick, the dark gray surface slightly roughened by minute tubercles.

Distribution. California, valley of the Sacramento River southward along the western slopes of the Sierra Nevada, and on the coast ranges and southern mountains to San Diego County; Arizona, Oak Creek and Sycamore Cañons, near Flagstaff, Coconino County, (_P. Lowell_), Copper Cañon, west of Camp Verde, Yavapai County, and on the Pinal and Santa Catalina Mountains.

Passing into

Rhamnus crocea var. insularis Sarg.

A form with larger less prominently toothed leaves sometimes 3′ long and 1½′ wide, rather larger flowers, with shorter and broader calyx-lobes a less deeply divided style, and larger fruits. A tree often growing to the height of 25°—30°, flowering later than the var. _ilicifolia_, and not uncommon on the islands of the Santa Barbara group and on the mountains of the adjacent mainland. A form (f. _pilosa_ Trel.) with narrow revolute leaves densely pilose throughout, occurs in the Santa Maria valley of the mountains near San Diego.

2. Rhamnus caroliniana Walt. Indian Cherry.

Leaves deciduous, elliptic-oblong or broad-elliptic, acute or acuminate, cuneate or somewhat rounded at base, remotely and obscurely serrate, or crenulate, densely coated when they unfold with rusty brown tomentum, and at maturity thin, dark yellow-green above, paler below, glabrous or somewhat hairy on the lower surface, 2′—6′ long and 1′ to nearly 2′ wide, with a prominent yellow midrib and about 6 pairs of conspicuous yellow primary veins; turning yellow in the autumn before falling; petioles slender, pubescent, ½′ to nearly 1′ in length; stipules nearly triangular. Flowers appearing from April to June when the leaves are almost fully grown, on slender pedicels about ¼′ long, in few-flowered pubescent umbels, on peduncles varying from ⅛′—½′ in length; calyx 5-lobed, with a narrow turbinate tube and triangular lobes; petals 5, broad-ovate, deeply notched at apex and folded round the short stamens; ovary contracted into a long columnar style terminating in a slightly 3-lobed stigma. Fruit ripening in September and sometimes remaining on the branches until the beginning of winter, globose, ⅓′ in diameter, black, with thin sweet rather dry flesh and 2—4 nutlets; seeds obtuse at apex, rounded on the back, reddish brown, about ⅕′ long.

A tree, 30°—40° high, with a trunk 6′—8′ in diameter, small spreading unarmed branches, and slender branchlets light red-brown and puberulent or covered with a glaucous bloom when they first appear, becoming slightly angled, gray, and glabrous, and marked during their second season by the small horizontal oval leaf-scars; more often a tall shrub, with numerous stems 15°—20° high. Winter-buds naked, hoary-tomentose. Bark of the trunk about ⅛′ thick, slightly furrowed, ashy gray and often marked by large black blotches. Wood rather hard, light, close-grained, not strong, light brown, with lighter colored sapwood of 5 or 6 layers of annual growth.

Distribution. Borders of streams on rich bottom-lands, and on limestone ridges; Virginia to western Florida and westward through the valley of the Ohio River to southern Iowa and southeastern Nebraska, eastern Kansas, the valley of the Washita River, Oklahoma (Ardman County), and to Kendall, Kerr and Uvalde Counties, western Texas; occasionally tree-like in western Florida and Mississippi, and of its largest size only in southern Arkansas and the adjacent portions of Texas; very abundant on the limestone barrens of central Kentucky and Tennessee.

3. Rhamnus Purshiana DC. Bearberry. Coffee-tree.

Leaves deciduous, broad-elliptic, obtuse or bluntly pointed at apex, rounded or slightly cordate at base, finely serrate, or often nearly entire, with undulate margins, thin, villose with short hairs on the lower surface and on the veins above, 1½′—7′ long, 1½′—2′ wide, conspicuously netted-veined, with a broad and prominent midrib and primary veins; turning pale yellow late in the autumn before falling; petioles stout, often pubescent, ½′—1′ in length; stipules membranaceous, acuminate. Flowers on slender pubescent pedicels ¼′—1′ long, in axillary cymes on slender pubescent peduncles ½′—1′ in length on shoots of the year; calyx nearly campanulate, with 5 spreading acuminate lobes; petals 5, minute, ovate, deeply notched at apex, and folded round the short stamens; stigma 2 or 3-lobed. Fruit globose or broad-obovoid, black, ⅓′—½′ in diameter, slightly or not at all lobed, with thin rather juicy flesh, and 2 or 3 obovoid nutlets usually ⅓′ long, rounded on the back, flattened on the inner surface, with 2 bony tooth-like enlargements at base, 1 on each side of the large scar of the hilum, and a thin gray or pale yellow-green shell; seeds obtuse at apex, rounded on the back, seed-coat thin and papery, yellow-brown on the outer surface, bright orange color on the inner surface like the cotyledons.

A tree, 35°—40° high, with a slender trunk often 18′—20′ in diameter, separating 10°—15° from the ground into numerous stout upright or sometimes nearly horizontal branches, and slender branchlets coated at first with fine soft pubescence, pale yellow-green or reddish brown, and pubescent, glabrous, or covered with scattered hairs in their second season and then marked by the elevated oval horizontal leaf-scars; often shrubby and occasionally prostrate. Winter-buds naked, hoary-tomentose. Bark of the trunk rarely more than ¼′ thick, dark brown to light brown or gray tinged with red, broken on the surface into short thin scales. Wood light, soft, not strong, brown tinged with red, with thin lighter colored sapwood. The bark possesses the drastic properties peculiar to that of other species of the genus, and is a popular domestic remedy in Oregon and California, and under the name of Cascara Sagrada has been admitted into the American materia medica.

Distribution. Rich bottom-lands and the sides of cañons, usually in coniferous forests; shores of Puget Sound eastward along the mountain ranges of northern Washington to the Bitter Root Mountains of Idaho and the shores of Flat Head Lake, Montana, and southward to central California; Arizona, southern slope of the Grand Cañon of the Colorado River, Coconino County (_A. Rehder_), Cave Creek Cañon, Chiricahua Mountains, Cochise County (_J. W. Toumey_).

Occasionally cultivated in the gardens of western Europe and of the eastern United States.

5. CEANOTHUS L.