Senna timoriensis

Author: (De Candolle) Irwin & Barneby

K. & S.S. Larsen in Fl. Camb., Laos & Vietn. 18 (1980) 88, pl. 1/5; in Fl. Thail. 4 (1984) 111, f. 27/5

Morphological description (timoriensis Senna lf/pod FT27 )
Small tree , rarely above 10 m tall; young branches and leaves varying in hairiness from subglabrous to velutinous in yellow to golden colours. Stipules auriculate, 1.5-2 cm.

Leaves paripinnate with 10-20 pairs of leaflets; petiole 1-2 cm; rachis 20-30 cm, pubescent. Leaflets with a short petiolule, oblong, 2-6 by 1-1.5 cm with rounded base and subacute to mucronate apex, from nearly glabrous to yellowish pubescent on both sides.

Inflorescences axillary, dense racemes, 10-30 cm long; axis more or less glabrous to yellowish pubescent; bracts caducous, ovate, acute, up to 20 by 15 mm; bracteoles absent;pedicels 1-3 cm, pubescent.

Flower: Sepals 5, unequal, oblong-ovate with rounded apex, 7-15 mm long, yellowish pubescent outside. Petals 5, yellow, obovate, short-clawed, 15-20 by 10-15 mm. Stamens: 2 largest with filaments 2-4 mm and anthers 8-10 mm long opening by apical pores; 5 somewhat smaller opening in the same way; staminodes 3, c. 2 mm; filaments of all stamens straight. Ovary more or less glabrous; style glabrous; stigma inconspicuous.

Pods flat, glabrous, dehiscent, 8-16 by 1-1.5 cm.

Seeds 10-30, elliptic, glossy, flattened, 7 by 5 mm.

From Sri Lanka throughout SE Asia to N Australia.

Habitat & Ecology
Seems to prefer calcareous soil. It is always growing in light-open forests up to 1100 m, e. g. in the deciduous dipterocarp forests. It is often seen as a pioneer species in forest margins towards clearings. It flowers throughout the year.

The wood is highly resistant to insect attacks and frequently used for various construction purposes. Young leaves are edible. The pods are locally used in medical treatments of e. g. worms. It is also planted as wayside tree and in Timor it is used in mixed afforestations for soil protecting purposes. See Heyne (1950: 748); Burkill (1935: 481).