膏桐树(Jatropha curcas Linn.)也叫麻风树、小桐子树,为大戟科麻风树属植物。灌木,高2至4米,多分枝,灰绿色。枝条圆柱形,近肉质。富有弹性。叶互生,长10至15厘米,宽7.5至12.5厘米,光滑,阔卵形,全缘或有角或掌状三至五裂。叶基心脏形,尖端急尖,掌状脉,叶柄长。聚繖花序腋生,花淡黄绿色,长约7毫米。肉质蒴果长2.5厘米,成熟后干裂为三个两爿的小分果。种子卵形至长椭圆形,深棕至棕黑色。高温多雨时开花,冬季落叶后果熟。膏桐原产热带美洲,因其极耐干热气候和瘠薄土壤且有很强的繁殖能力,现已几乎遍布于全球各热带和高热量地区。尤其在一些热带岛屿,常为优势种植物而形成纯群落。我国云南、四川、贵州、广东、广西皆 Jatropha curcas (Jatropha curcas Linn.) Also known as Jatropha, Jatropha curcas, Euphorbiaceae Jatropha. Shrubs, 2 to 4 meters tall, much branched, gray-green. Branches cylindrical, nearly succulent. Flexible. Leaves alternate, 10 to 15 cm long, 7.5 to 12.5 cm wide, smooth, broadly ovate, entire or angled or palmately three to five-lobed. Leaf base heart-shaped, sharp tip sharp, palmate veins, petiole long. Cymes axillary, flowers yellowish green, ca. 7 mm. The fleshy capsule is 2.5 centimeters long, and the mature fissures are three small flesh of two flesh. Seeds ovate to oblong, dark brown to dark brown. Flowering when hot and rainy, winter deciduous fruit cooked. Tongti native tropical Americas, because of its extremely resistant to dry and hot climate and barren soil and has strong reproductive capacity, is now almost all over the world in tropical and high calorie areas. Especially in some tropical islands, the dominant species often form pure communities. Our country Yunnan, Sichuan, Guizhou, Guangdong, Guangxi Jie