Rhamnus tangutica J. Vass.

The fruit is used for making dye.

This species is quite similar to Rhamnus virgata, but the latter dif-fers in having young branches hairy and leaves thin, concolorous on both surfaces, turning red when dry, with conspicuous reticulate veins.

Shrubs, rarely trees, dioecious, 2-6 m tall, spinose. Branchlets opposite or subopposite; young branches green, glabrous or subglabrous; older branches red-brown or black-brown, smooth, shiny, terminating in a spine. Leaves opposite or subopposite, or fascicled on short shoots; stipules linear, often persistent; petiole to 1.3 cm; leaf blade abaxially pale green, turning yellow when dry, adaxially dark green, elliptic, obovate-elliptic, or obovate, 2.5-6 × 1-3.5 cm, papery or thickly papery, abaxially sparsely puberulent on veins and vein axils, adaxially sparsely shortly hairy or subglabrous, lateral veins 4 or 5 pairs, base cuneate, margin obtuse or crenulate, apex shortly acuminate or acute, rarely subrounded. Flowers unisexual, 4-merous. Pedicels 4-6 mm, glabrous or subglabrous. Petals present. Male flowers few to 10. Female flowers 3-9-fascicled on short shoots; style 2-fid. Drupe black at maturity, obovoid-globose, 4-6 mm in diam., with persistent calyx tube at base, with 2 stones; fruiting pedicel 6-8 mm, glabrous. Seeds red-brown, abaxially-laterally with margined furrow extending over 3/4-4/5 of length. Fl. May-Jun, fr. Jun-Sep.

S Gansu, W Henan, Qinghai, C Shaanxi, W Sichuan, E Xizang.

● Forests and thickets in valleys; 1200-3700 m.

Rhamnus leptophylla C. K. Schneider var. scabrella Rehder; R. potaninii J. J. Vassiljev; R. virgata Roxburgh var. parvifolia Maximowicz.