杜仲科Eucommiaceae

落叶乔木；树体各部均具胶质。单叶互生，羽状脉，有锯齿；无托叶。花单性异株，无

花被，簇生或单生；雄蕊4～10；雌蕊由2心皮组成，子房上位，l室。翅果，含1粒种子。本科仅1属1种，我国特产。

杜仲属EucommiaOliv.

本属仅杜仲1种，特征同科。

杜仲Eucommia ulmoides Oliv.

杜仲

【形态】：落叶乔木，高达20m，胸径1m；树冠圆球形。小枝光滑，无顶芽，具片状髓。叶椭圆状卵形，长7～350px，先端渐尖，基部圆形或广楔形，缘有锯齿。翅果狭长椭圆形，扁平，长约87.5px，顶端2裂。本种枝、叶、果及树皮断裂后均有白色弹性丝相连。花期4月，叶前开放；果～11月成熟。

【分布】：原产中国中部及西部，四川、贵州、湖北为集中产区。

【习性】：喜光，不耐庇荫；喜温暖湿润气候及肥沃、湿润、深厚而排水良好之土壤。

【繁殖】：主要用播种法繁殖，扦插、压条及分蘖或根插也可。

【用途】：杜仲多作庭荫树及行道树，也可作一般的绿化造林树种。是著名的药材。

Eucommia ulmoides

Common name: 

Hardy Rubber Tree

Gutta-percha Tree

Pronunciation: 

u-KOM-i-a ul-MOY-dez

Family: 

Eucommiaceae

Genus: 

Eucommia

Type: 

Broadleaf

Native to (or naturalized in) Oregon: 

No

• Broadleaf deciduous tree, 40-60 ft (12-18 m) high and 30-50 ft wide (9-15 m), rounded to broad spreading at maturity.  Leaves alternate, simple, 8-15 cm long and about half as wide, elliptic, ovate, to oblong-ovate, tip acuminate, margin serrate, glossy dark green, somewhat rugose (wrinkled) when mature, when the blade is torn it exhibits a rubbery latex (see below).  Dioecious - male and female trees, flowers small, greenish-brown, inconspicuous.  Fruit flat, waxy surface, oval-oblong, about 4 cm long, a notch at the apex, 1-seeded, resembling a large, fleshy elm fruit.

• Sun.  Free of pests.