What Is Rhamnus Frangula?

Rhamnus (scientific name: Rhamnus L.) Rhamnaceae, including Frangula Mill. About 200 species are widely distributed throughout the world. There are 57 species and 14 varieties in China. ^{[1] They} are distributed from north to south, some of which are used for dyes and medicines. Use or watch. Deciduous or evergreen shrubs or trees; leaves alternate, sparsely opposite, pinnate veins, entire or dentate; flowers small, pale green or pale yellow, bisexual or unisexual, forming axillary cymes, umbrella-shaped Inflorescences or racemes; calyx 4-5 cleft; petals 4-5 or absent; stamens 4-5; ovary 2-4 compartments, separated from disk; style undivided or 3-4 cleft; fruit is a berry Drupe-like, with 3 to 4 nucleus, surrounded by persistent calyx tube. ^[2]

Shrubs or trees, thornless or twigs often turning into needles; buds exposed or scaly.

Leaves alternate or nearly opposite, sparsely opposite, pinnately veined, edges serrated or sparsely entire; stipules small, early falling, sparsely persistent. Flowers small, bisexual, or unisexual, dioecious, sparse, solitary or several clusters, or arranged in axillary cymose, cymose or cymose panicle, yellow-green; calyx campanulate or funnel Campanulate, 4-5 lobed, sepals ovate-triangular, with raised middle ribs; petals 4-5, shorter than sepals, pocket-shaped, short claw at base, often 2 lobed at apex, sparsely petalless; 4-5, carrying a medicine, held by petals, as long as or shorter than petals; disk thin, cup-shaped; upper ovary, spherical, born on disk, not surrounded by disk, 2-4 chambers , 1 ovule per chamber, style 2-4 cleft.

Berry-shaped drupe obovate or spheroid, surrounded by persistent calyx tube, with 2-4 subnucleus, nucleus bone or cartilage, cracked or not cracked, each with 1 seed; seeds obovate or oblong Oval-shaped, with longitudinal grooves on the back or dorsal side, or sparsely grooveless. ^[1]

About 200 species of this genus are distributed from temperate to tropical, mainly concentrated in eastern Asia and southwestern North America, and a few are also distributed in Europe and Africa. There are 57 species and 14 varieties in China, which are distributed in various provinces and regions of the country, with the largest number in Southwest and South China. ^[3]

The scope of this genus had two different concepts, broad and narrow. In a broad sense, it includes the naked bud subgenus and scaly subgenus. In the narrow sense, the naked bud subgenus is separated from the genus as an independent genus. K. Suessenguth (1953) based on the classification of Heppler (1928), based on whether the genus has scales, buds, grooves, flower bases, and petals; the texture of the mesocarp and the presence or absence of spines in the plant This genus is divided into two subgenus, namely naked subgenus and scaly subgenus, and has 22 lines. In contrast, Soviet scholars (Grubow 1949) proposed another classification system. In this system, in addition to the naked subgenus as a separate genus, there are 7 groups in the genus Rhamnus (narrowly defined). And 4 subgroups as well as Ruoqian line. The genus includes the broad concept of naked subgenus and subgenus Lepidoptera, and the sub-genus mainly adopts the grouping arrangement of Grubow. ^[3]

Thyme leaf buckthorn Rhamnus serpyllifolia Lévl.
Subgen. Frangula (Mill.) SF Gray
Subgenus Subgen. Rhamnus ^[1]

Rhamnusdavurica Pall.

Shrubs or small trees, up to 10 meters; young branches glabrous, branchlets opposite or near opposite, brown or reddish brown, slightly smooth, often with large buds at the top of the branch without forming spines, or sometimes only short at the bifurcation Acupuncture; apical buds and axillary buds are larger, oval, 5-8 mm long, scales light brown, with obvious white marginal hairs. Leaves papery, opposite or nearly opposite, or clustered on short branches, broadly elliptic or oval, thinly oblanceolate-elliptic, 4-13 cm long, 2-6 cm wide, apex pointed or Short acuminate to acuminate, blunt or round, base wedge-shaped or nearly round, sometimes sparsely skewed, margins with scalloped fine serrations, often with red glands at the ends of the teeth, hairless or sparse along the veins Hairy, white sparsely hairy along veins, 4-5 (6) strips on each side of side veins, raised on both sides, with obvious reticulate veins; petiole 1.5-5 cm long, glabrous or sparsely hairy on top. Flowers unisexual, dioecious, 4 bases, with petals, female flowers 1-3 born in leaf axils or several to more than 20 clusters at short branch ends, degenerate stamens, styles 2-3 lobed or semi-lobed; pedicels 7-8 mm long. Drupe globose, black, 5-6 mm in diameter, with 2 nucleus, persistent calyx tube at base; fruit pedicel 1-1.2 cm long; seeds oval, yellow-brown, dorsal narrowly longitudinal ditch. Flowering from May to June, fruit from July to October. ^[4]

Most types of fruits contain yellow dyes; seeds contain fatty oils and proteins, and oil is pressed for lubricating oils and inks, soaps, and a few species of bark, roots, and leaves are available for medicinal purposes. Most species also have significant value in landscaping. ^[3]