Cassia fistula Linn., Sp. Pl. 377. 1753. Baker in Hook. f., Fl. Brit. Ind. 2: 261. 1878; Ali & S. Quraishi in S.U. Sci. Res. J. 3: 5. 1967.
Tree, up to 20 m tall. Bark in young tree smooth and ash coloured becoming rough and dark brown in old. Stipules deltoid, acute, 1-2 mm long, caducous. Rachis 12-25 cm long, terete, glabrous. Leaves compound 22.5-40 cm long, with 3-8 pairs of opposite leaflets, 6-10 (20) cm long, smooth above, hairy below. Flowers arranged in drooping racemes, each raceme c. 10-45 cm long; peduncle 2-10 cm long. Pedicel 3.7-5.8 cm long, slender, slightly hairy or quite smooth, bracts 8-10 mm long, ovate, acute, hairy. Calyx 5, green, folded backward on the stalk, hairy, ovate, 9 mm long. Petals 5, obovate, blunt, distinctly veined. Stamens 10, 3 longest stamens much curled and bear large oblong anthers, 4 smaller medium ones are quite straight, 3 remaining stamens are quite short, erect and sterile. Ovary slender, thinly appressed hairy, style sturdy, stigma punctiform. Pods terete, glabrous, indehiscent, 40-60 cm long, 1.5-2 cm broad, black glossy brown, 40-100 seeded.
Fl. Per.: April June.
Type: Herb. Linn. 528/15 (LINN).
Distribution: W. Pakistan, Swat and Hazara eastwards, ascending to 4000 ft. and commonly planted in gardens; common in deciduous forests throughout the greater part of India, Burma and Ceylon.
An ornamental tree, the bark is used as tanning material and wood ash is used as mordant in dyeing. The pulp of pods is used in Bengal to flavour tobacco. The durable wood is used for various purposes. Various parts of the plant are also reputed to have medicinal properties.