2. Bombax ceiba Linnaeus, Sp. Pl. 1: 511. 1753.
木棉 mu mian
Bombax malabaricum Candolle; Gossampinus malabarica (Candolle) Merrill; Salmalia malabarica (Candolle) Schott & Endlicher.
Trees to 25 m tall; trunk buttressed, usually very spiny on young trees; bark gray-white; branches spreading. Stipules minute; petiole 10-20 cm; leaflets 5-7, petiolules 1.5-4 cm; blades oblong to oblong-lanceolate, 10-16 × 3.5-5.5 cm, glabrous, lateral veins 15-17 on each side of midrib, ascending, base broad or tapering, apex acuminate. Flowers solitary, terminal, ca. 10 cm in diam. Calyx cup-shaped, 2-3(-4.5) cm, abaxially glabrous, adaxially densely yellowish sericeous, calyx lobes 3-5, semi-orbicular, ca. 1.5 × 2.3 cm. Petals usually red, sometimes orange-red, obovate-oblong, 8-10 × 3-4 cm, fleshy, both surfaces stellate puberulent, but sparser adaxially. Filament tube short, filaments thicker at base than apex, outer series in 5 fascicles, each with more than 10 stamens, inner series bifid, central filaments with 10 stamens shorter, entire. Capsule ellipsoid, 10-15 × 4.5-5 cm, densely gray-white villous and stellate puberulent. Seeds many, obovate, smooth. Fl. Mar-Apr, fr. summer.
Hot dry river valleys, savanna; below 1400 m. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Jiangxi, Sichuan, Taiwan, Yunnan [Bangladesh, Bhutan, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Papua New Guinea, Philippines, Sri Lanka; introduced elsewhere].
Bombax ceiba was formerly cultivated for its seed floss (kapok), which is of lower quality than that from Ceiba pentandra. Bombax ceiba var. leiocarpum A. Robyns, distinguished by the glabrous ovary and fruit, is found in N Australia.