Description from Flora of China
Ilex japonica Thunberg in Murray, Syst. Veg., ed. 14, 168. 1784; Berberis japonica (Thunberg) R. Brown; B. japonica var. gracillima (Fedde) Rehder; B. tikushiensis (Hayata) Laferrière; Mahonia japonica var. gracillima Fedde; M. tikushiensis Hayata.
Shrubs, ca. 1 m tall. Leaves abaxially pale green, adaxially deep green, oblong, 15-27 × 5-10 cm, with 4-6 pairs of sessile leaflets, lowest pair ca. 0.5 cm above base of petiole, abaxially not pruinose, with branched raised venation; rachis 2-3 mm in diam.; internodes 2-4 cm, decreasing in length upward; leaflets ovate, lowest 1.8-2.7 × 1.2-2 cm, becoming larger upward, 3.5-7 × 2-4 cm, base oblique and ± cordate, margin with 2-4 teeth on proximal side, 3-7 teeth on distal margin, apex acute; terminal leaflet larger, ± cordate at base, petiolule 1-2 cm. Inflorescence 5-10-fascicled drooping racemes, 5-10 cm; bracts of inflorescence ovate to ovate-lanceolate, 0.8-1.5 cm × 4-7 mm, apically acuminate. Pedicel 6-7 mm; floral bracts ovate, 3.5-4 × 2-2.5 mm, apex obtuse. Sepals yellow; outer sepals ovate, 2.5-2.7 × 2.2-2.3 mm, apically obtuse; median sepals broadly obovate, 3.3-3.5 × 2.8-2.9 mm; inner sepals obovate-oblong, 6-6.4 × 3.4-3.5 mm. Petals elliptic, 5.5-6 × 2.5-2.6 mm, base with distinct glands, apex emarginate. Stamens ca. 3.3 mm; anther connective slightly prolonged, rounded. Ovary ca. 3.4 mm; ovules 4-7. Berry dark purple, ± pruinose, ovoid, ca. 8 × 4 mm; style persistent and short, or not persistent. Fl. Dec-Apr, fr. Apr-Aug. 2n = 28*.
This species is cultivated extensively in Japan and sporadically in the warmer parts of Europe and the United States.
● Forests, thickets; 800-3400 m. Taiwan.