Description from Flora of China
Bombax pentandrum Linnaeus, Sp. Pl. 1: 511. 1753; Eriodendron anfractuosum Candolle.
Trees to 30 m tall; buttresses small or absent, trunk often sparsely spiny; main branches verticillate, spreading horizontally; young branches spiny. Petiole 7-14(-25) cm, longer than leaflet blade; leaflets 5-9, petiolules 3-4(-10) mm; blades oblong to lanceolate, 5-20 × 1.5-6.5 cm, thinly leathery, glabrous, base acuminate, margin entire or very sparsely and minutely toothed near apex, apex shortly acuminate. Flowers subterminal, solitary or in fascicles of up to 15, produced before or simultaneous with new leaves. Pedicel (1.8-)2.5-5 cm. Calyx (0.9-)1.2-2 cm, adaxially glabrous. Petals pink or white, obovate-oblong, 2.5-4 × 0.7-1.5 cm, abaxially densely white villous, adaxially glabrous. Filaments on staminal tube varying in length; anthers reniform. Ovary glabrous; style 2.5-3.5 cm; stigma rod-shaped, 5-lobed. Capsule oblong, tapering toward tip, 7.5-15(-26) × 3-5(-11) cm, fruiting pedicel 7-25 cm, endocarp leathery, smooth. Seeds globose, ca. 6 mm in diam. Fl. Mar-Apr.
This species is grown as a street tree and for the waterproof fibers surrounding the seeds (kapok).
Cultivated. Guangdong, Guangxi, Yunnan [native to tropical America and possibly West Africa; now pantropical, regarded as invasive on some Pacific islands].