Description from Flora of China
Manihot curcas (Linnaeus) Crantz.
Shrubs or treelets, 2-5 m tall, with watery latex; bark smooth; branches glaucous-gray, glabrous, sparsely lenticellate, pith larger. Stipules small; petioles 6-18 cm; leaf blade rotund to ovate, 7-18 × 6-16 cm, papery, nitid green and glabrous adaxially, gray-green and along nerves puberulent to glabrous abaxially, base cordate, apex acute; palmate veins 5-7. Inflorescences axillary, 6-10 cm; bracts lanceolate, 4-8 mm. Male flowers: sepals 5, ca. 4 mm, connate at base; petals oblong, green-yellow, ca. 6 mm, connate to middle, hairy inside; disk glands 5, nearly terete; stamens 10; outer 5 filaments free, inner filaments connate in lower part. Female flowers: pedicels elongate; sepals free, ca. 6 mm; petals and disk glands as in male; ovary 3-locular, glabrous; styles bifid at apex. Capsules ellipsoidal or globose, 2.5-3 cm, yellow. Seeds ellipsoidal, 1.5-2 cm, black. Fl. Sep-Oct, fr. Oct-Dec.
Jatropha curcas seeds are the source of curcas oil, a very powerful purgative, also used for making candles and soap, for lighting, and as a lubricant. There is interest in the oil as a biofuel crop for areas too dry for normal crops. The bark is used as medicine for lepriasis (leprosy), itchy skin, eczema, chronic ulcers, etc.
Cultivated for medicine. Fujian, Guangdong, Guangxi, Hainan, Sichuan, Taiwan, Yunnan [native to tropical America; widely introduced].