Japan Flora: Dioecious shrub; prickles on branches at base of leaves 2, 5-8 mm. long; leaves puberulous while young, 5-15 cm. long, short-petiolate, the leaflets 11-19, sessile, broadly lanceolate to ovate, 1-35 cm. long, 6-12 mm. wide, emarginate, cuneate to obtuse at base, obtusely toothed with pellucid glands in the sinus; inflorescence terminal on short branches, pedunculate, many-flowered; flowers greenish yellow, small. Apr.-May. Hills and mountains.
Hokkaido, Honshu, Shikoku, Kyushu; rather common and frequently cultivated. Korea, Manchuria, and China.
f. inerme (Makino) Makino. The seeds and young leaves are used as a spice and the plant is often planted for this purpose.
f. brevispinosa Makino. Prickles short. Intermediate between the typical phase and the preceding form.
f. ovalifoliolatum (Nakai) Makino. Leaflets 3-5, ovate. Rarely cultivated.
Korea Flora: Deciduous shrub. Height up to 3m. Winter buds and twigs: Naked, circular, small with rounded tips, 1.5-3mm. Terminal buds similar to lateral buds. Young branches hairy, but hair gradually disappears. Spines (modified stipules) opposite, slightly curved downward, 5-10mm long. Leaf scars: Semicircular or triangular. Leaves alternate, odd-pinnate compound leaves. 9-10 leaflets, ovate, elongated ovate, or slightly concave, with cuneate base. Size: 1-3.5cm × 0.5-1.2cm. 4-7 wavy teeth with glands at the lower part of teeth, leaf margins, and apex. Aromatic, with pale yellowish-green dots in the center. Rachis often has thorns. Flowers dioecious. compound racemes growing from leaf axils. Flowers pale yellowish-green, with 5 petals and stamens each. ovaries separate with stalks at the base. reddish-brown with glands. Seeds black.
Sporophyte chromosome number: 70
Flowering May-June
Fruiting Late September to early October
Distribution: Throughout Japan; mainly in Gyeonggi-do, North and South Chungcheongnamdo, Chungcheongbukdom Jeollanamdo, Jeollabukdo and Gyeongsangnamdo, Gyeonsangbukdo in Korea. In Gangwondo, found in coastal areas like Seoraksan and Geumgangsan.
Ecological characteristics: Weak to cold (below -10 to -15°C). Very distinct light-demanding species with weak shade tolerance. Does not grow well in shallow, dry soils, windy areas, shaded places, or areas with heavy snow.