中文名（Chinese Name）：丝棉木
学名（Scientific Name）：Euonymus maackii Rupr.
英文名（English Common Name）：
别名（Chinese Common Name）：白肚
异名（Synonym）：Euonymus forbesii Hance  Euonymus bungeanus Maxim.  Euonymus bungeanus var. ovatus F. H. Chen et M. C. Wang  Euonymus bungeanus var. latifolius C. H. Wang  Euonymus bungeanus var. mongolicus (Nakai) Kitag.  Euonymus mongolicus Nakai  Euonymus maackii f. salicifolius T. Chen  Euonymus maackii var. trichophyllus Y. B. Chang  Euonymus oukiakensis Pamp.  Euonymus maackii f. lanceolatus Rehder  Euonymus hamiltonianus var. semiperssistens Rehder ex Bailey  Euonymus bungeanus f. pendulus Rehder  Euonymus quelpaertensis Nakai  Euonymus europaea var. maaekii (Rupr.) Regel  Euonymus hamiltoniana var. maaekii (Rupr.) Kom.  Euonymus semipersistens (Rupr.) Sprague ex Bean  Euonymus coreana H. Lév.  Euonymus bungeanus var. semipersistens (Rehder ex L.H.Bailey) C.K.Schneid.  Euonymus trapococcus Nakai  Euonymus coreanus H.Lév.  Euonymus hamiltonianus var. semipersistens Rehder ex L.H.Bailey
科属（Family & Genus）：卫矛科（Celastraceae）卫矛属
形态特征（Description）：小乔木，高达6米。叶卵状椭圆形、卵圆形或窄椭圆形，长4-8厘米，宽2-5厘米，先端长渐尖，基部阔楔形或近圆形，边缘具细锯齿，有时极深而锐利；叶柄通常细长，常为叶片的1/4-1/3，但有时较短。聚伞花序3至多花，花序梗略扁，长1-2厘米；花4数，淡白绿色或黄绿色，直径约8毫米；小花梗长2.5-4毫米；雄蕊花药紫红色，花丝细长，长1-2毫米。蒴果倒圆心状，4浅裂，长6-8毫米，直径9-10毫米，成熟后果皮粉红色；种子长椭圆状，长5-6毫米，直径约4毫米，种皮棕黄色，假种皮橙红色，全包种子，成熟后顶端常有小口。花期5-6月，果期9月。
分布（Distribution）：除陕西、西南及两广外没有野生外，其他各省区均有。俄罗斯、朝鲜及日本也有。
用途（Use）：
引自中国植物志英文版FOC Vol. 11 Page 455, 459
Euonymus maackii Ruprecht, Bull. Cl. Phys.-Math. Acad. Imp. Sci. Saint-Pétersbourg. 15: 358. 1857.
白杜 bai du| Celastraceae  | Euonymus
Euonymus bungeanus Maximowicz; E. bungeanus var. latifolius Chen H. Wang; E. bungeanus var. mongolicus (Nakai) Kitagawa; E. bungeanus var. ovatus F. H. Chen & M. C. Wang; E. bungeanus f. pendulus Rehder; E. forbesii Hance; E. hamiltonianus Wallich var. semipersistens Rehder; E. maackii f. lanceolatus Rehder; E. maackii f. salicifolius T. Chen; E. maackii var. trichophyllus Y. B. Chang; E. micranthus Bunge; E. mongolicus Nakai; E. oukiakensis Pampanini.
Deciduous shrubs to trees, 3-10 m tall, to 15 cm d.b.h.; branches and twigs terete, sturdy, green to light green. Petiole 1-2.5 mm; leaf blade thinly leathery or thickly papyraceous, ovate, orbicular-ovate, elliptic, or ovate-lanceolate, 6-10.5 × 2-4 cm, base subattenuate, margin crenulate, apex acute or acuminate, sometimes caudate, both surfaces smooth; lateral veins 6-8 pairs, curving forward, webbing and disappearing before reaching margin. Peduncle 2-3.5 cm, 1-3 × dichotomously branched, several flowered; pedicel 5-7 mm. Flowers 4-merous, 8-9 mm in diam.; sepals ovate; petals white, lanceolate or long ovate, apex acuminate or obtuse. Capsule rhombic, with 4 angles and deep grooves, base attenuate, brown or yellow-brown to red-brown, ca. 8 × 9 mm. Seeds subglobose, dark brown, partially covered by orange aril. Fl. Apr-Jul, fr. Aug-Nov.
Edges of woodlands and forests; near sea level to 1000 m. Anhui, Gansu, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Ningxia (cultivated), Qinghai (cultivated), Shaanxi, Shandong, Shanxi, Sichuan (cultivated), Xinjiang, Yunnan, Zhejiang [Japan, Korea, Russia (Far East); cultivated in Europe and North America].
This is one of the most common species in the genus. Its growth is quite variable under both cultivated and wild conditions.（责任编辑：徐晔春）