白薷 bai ru

Shrubs scandent. Branchlets brownish to dark reddish brown, initially grayish yellow tomentose, glabrescent, with sparse, curved minute prickles; flowering branchlets shortly stipitate glandular. Leaves simple; petiole 1–2 cm, grayish yellow tomentose-villous, glabrescent, with shortly stipitate glands; stipules oblong-lanceolate, 1–1.5 cm × 3–5 mm, membranous, pubescent, margin entire, apex acute or obtuse; blade ovate or broadly ovate to ovate-lanceolate, 6–9 × 4–6 cm; lateral veins 7–9 pairs, slightly raised abaxially, abaxially usually persistently densely gray tomentose, adaxially glabrous except slightly pubescent along midvein, base rounded or truncate to shallowly cordate, margin shallowly undulate, rarely inconspicuously lobed, with irregular minute sharp serrations, apex shortly acuminate to caudate. Inflorescences terminal, rarely axillary, narrow racemes, 6–10 cm, 6–15(–20) flowered; rachis and pedicels tomentose-villous, with short stalked glands 1–2 mm; bracts oblong-lanceolate, 0.8–1.4 cm × 3–4 mm, membranous, pubescent, margin entire, apex ± obtuse. Pedicel 1–1.5 cm. Calyx abaxially tomentose-villous, stipitate glandular; sepals often reflexed in fruit, lanceolate or triangular-lanceolate, 1–1.2 cm, margin entire, apex shortly caudate. Petals white, obovate or orbicular, nearly as long as sepals, slightly pubescent, base clawed. Stamens many, shorter than petals; filaments linear or with broad flat base, glabrous or slightly soft hairy only on anthers. Pistils many, slightly longer than stamens; style and ovary glabrous. Aggregate fruit black at maturity, subglobose, ca. 1.5 cm in diam.; pyrenes reticulate. Fl. May–Jul, fr. Aug–Sep.

Mixed forests, valleys, ravines; 2000--3200 m. N Yunnan.

The seeds are widely used medicinally in Yunnan.