Guaicum officinale Linn., Sp. P1. 381. 1753. Bailey, Stand. Cycl. Hort. 2: 1414. 1950; Blatter & Millard, Beaut. Ind. Trees ed. 2. 90. 1954; Engler in Engler & Prantl, l.c. 167. fig. 77.
A small tree, 6-10 m tall. Branches knotted at the nodes, older rugose, with deeply furrowed bark, young ones minutely pubescent. Leaves abruptly paripinnate, with 2-3 pairs of sessile, 1.5-4.5 cm long, 1.0-2.5 cm broad, elliptic-rotund or obovate, obtuse leaflets, uppermost pair largest, leaflets of lowest pair unequal. Flowers showy, c. 2.5 cm across, bluish purple, fading to white; pedicel 1.5- 2 cm long; disc annular, fleshy, with nectiferous glands. Sepals 5,2 outer very broadly ovate, 3 inner broadly oblong, hairy, purplish-green. Petals 5, shortly clawed, 12-13 mm long, 6-7 mm broad, obovate, mucronate, hairy, bluish-purple. Sta¬mens 10, free, equal, filaments 6-7 mm long, bluish-purple. Ovary bicarpellate, syncarpous, stipitate, 2-loculed, laterally compressed, clavate with 2 lateral ridges and 2 central furrows; style twisted. Capsule compressed, winged, orange-yellow, somewhat retuse, mucronate, 1-seeded by abortion. Seeds pendulous, perisperm red, testa black.
Fl. Per.: March-October.
Type: Herb. Linn. 532. 1 (LINN).
Distribution: A native of S America and West Indies; introduced in Pakistan and other countries.
Cultivated along roadsides in Karachi for its dense crown of close growing foliage and showy flowers. The greenish brown resin yields a drug known as ‘Guaicum’. The hardest and heaviest of woods called “lignum vitae” is a remedy against morbus gallicus. The wood is extensively used for making blocks and pulleys, rulers and many other similar articles.