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.