Description from Flora of China
Macrocarpium officinale (Siebold & Zuccarini) Nakai.
Trees or shrubs, 4–10 m tall; axis sympodial. Bark grayish brown; winter leaf buds terminal or axillary, solitary or associated with flower buds; flower buds terminal, pubescent with yellowish brown short trichomes. Leaf blade abaxially light green, ovate-lanceolate or ovate-elliptic, 5.5–10 × 2.5–4.5 cm, abaxially sparsely pubescent with short appressed trichomes, axils of lateral veins with dense light brown long soft trichomes, veins 6 or 7. Umbellate inflorescences terminal; bracts ovate, 5–8 mm, papery to leathery, pubescent; peduncle ca. 2 mm, thick, pubescent. Pedicels 0.5–1 cm, slender, densely pubescent with soft trichomes. Calyx teeth broadly triangular, ca. 0.6 mm. Petals reflexed, ligulate-lanceolate, 2.5–3.3 × 1–1.3 mm. Stamens ca. 1.8 mm; anthers ellipsoid. Ovary obovoid, ca. 1 mm, densely pubescent; style ca. 1.5 mm. Fruit red or purplish red, narrowly ellipsoid, 1.2–1.8 × 0.5–0.7 cm; stones narrowly ellipsoid, ca. 1.2 cm, with a few unequal ribs. Fl. Mar–Apr, fr. Sep–Oct.
The fruit, called “zhu yu” or “zao pi” in Chinese medicine, is prescribed as an astringent tonic for impotence, spermatorrhea, lumbago, vertigo, and night sweats.
Forests, forest margins, mountain slopes; 400–1500(–2100) m. Anhui, Gansu, Henan, Hunan, Jiangsu, Jiangxi, Shaanxi, Shandong, Shanxi, Zhejiang [Japan, Korea].