喜树 xi shu

Camptotheca acuminata var. rotundifolia B. M. Yang & L. D. Duan; C. acuminata var. tenuifolia W. P. Fang & Soong; C. yunnanensis Dode.

Trees deciduous, to 20 m high; bark light gray, deeply furrowed; young branchlets purplish, villous, old branchlets glabrous. Petiole 1.5-3 cm; leaf blade abaxially greenish and lucid, oblong-ovate, oblong-elliptic, or orbicular, 12-28 × 6-12 cm, papery, slightly pubescent, lateral veins (4-)8-11(-15) pairs, base subrounded, margin entire, apex acute. Head terminal or axillary, often 2-9-flowered, 1.5-2 in diam.; bracts 3, triangular, 2.5-3 mm, both surfaces pubescent. Calyx cup-shaped, shallowly 5-lobed. Petals 5, light green, ca. 2 mm. Disk conspic- uous. Stamens 10, outer 5 longer than petals, glabrous. Style ca. 4 mm, glabrous; stigmas 2. Fruit thinly winged, gray-brown, 2.5-3.5 cm × 5-7 mm, smooth and lucid when dry. Seed 1; cotyledons lanceolate, 2-4 × ca. 1 cm, pinniveined, with 6-8 lateral veins on each side. Fl. May-Jul, fr. Sep. 2n = 44*.

● Forest margins, by streams; below 1000 m. Fujian, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Yunnan, Zhejiang [Vietnam].

This species is commonly cultivated mainly along roadsides.