Lagerstroemia reginae Roxb.

Lagerstroemia speciosa is a deciduous or semi-deciduous small to medium-sized or rarely large tree up to 40(45) m tall; bole fairly straight to crooked, branchless for up to 18 m, up to 100(-150) cm in diameter, often fluted and sometimes with small buttresses, bark surface smooth or with small papery flakes, grey to light fawn-brown mottled, inner bark fibrous, grey-fawn to yellow, turning dirty mauve or purple upon exposure; crown usually bushy and spreading. Leaves opposite, distichous, simple, entire, stipules minute or absent. Flowers in a large, axillary or terminal panicle, often showy, calyx funnel or bell shaped, 6(9) lobed, petals often 6, inserted near the mouth of the calyx tube, white to pink or purple, clawed, wrinkled, stamens many, in several rows, ovary superior, 3-6 locular with many ovules in each cell, style 1. Fruit a large woody capsule on the persistent calyx. Seed with an apical wing. The generic name commemorates M. Lagerstroem, 1691-1759, a Swedish patron of science and the specific epithet 'speciosa' is a Latin word for showy, referring to the flowers.

Trees shed leaves in the dry season. Saplings flower when only a few years old but viable seed production begins at 15 years old. Flowering is frequent, usually annually or even twice a year. Each flower lasts for only 2-3 days. In the Philippines, the tree flowers in April-June, in Java in July-October, and in Papua New Guinea in May-July, although flowers and fruits may be found throughout the year. Pollination is by large bees and seeds are dispersed by wind.

The tree requires fairly fertile soils.

It is found at low to medium altitudes in comparatively open habitats, in disturbed or secondary forest, grassland, and along rivers. The habitat may vary from well drained to occasionally flooded but not peat soil. It is resistant to fire.

L. speciosa is cultivated within its native range and in many other tropical countries.

The tree can be propagated by seed. Branch and root cuttings have been used occasionally and tissue culture has been successful on an experimental scale. Seeds should be sown in the shade, germination takes 15-56 days. After germination the small seedlings can be pricked out and transferred to containers. Stumps with a shoot length of 5-10 cm, a root length of 10-20 cm and a diameter of 5-25 mm have shown 90-100 % survival.

In trials in Java, 15-year-old trees attained a mean annual increment of 0.9-1.1 cm in diameter and 0.7-0.9 m in height. In trials at 3 m x 1 m on fertile soil in Java the canopy closed after 6 years and the first thinning was necessary after 8 years. Due to poor natural pruning a spacing of 2.5 m x 1 m is recommended. At 15.5 years the clear bole yield in the trial was 47-55 m cu/ha. It has been proposed to girdle trees 2 years before harvest to allow for easier seasoning. The tree coppices freely and is fairly resistant to fire.

The fungus, Rhizoctonia solani, causes leaf web blight in forest nurseries.

There are 165 000-235 000 seeds/kg. Seed storage behaviour appears to be orthodox. Viability maintained after 2 years hermetic storage at room temperature. Germination increases during the first 3-12 months of storage (Hong et.al, 1996).

Erosion control: Due to the tree’s dense and widespreading root system, it is used in erosion control. Reclamation: The tree has been used in reforestation of degraded hills in Java. Ornamental: L. spciosa is cultivated for ornamental purposes and as a roadside tree. Boundary or barrier or support: The tree is used as a support for rattan.

Fuel: The gross energy value of L. speciosa wood is 18 855-19 230 kJ/kg. Timber: The medium-weight hardwood has a density of 505-810 kg/cu m at 15 % moisture content. Heartwood pale brown, yellow-brown, greyish or reddish to red-brown, not differentiated from the white or grey-white to yellow-brown, up to 8 cm wide sapwood. Grain straight or slightly interlocked, occasionally conspicuously wavy, texture moderately fine to rather coarse, lustrous. The timber is resistant to termites. Tannin or dyestuff: Bark, fruit (14-17 %) and leaves (12-13 %) contain tannin. Lipids: Seeds of L. speciosa yield an oil whose main constituents are linoleic (54.3%), a keto (9-ketooctadec-cis-11-enoic acid, 21.1%), oleic (10.3%), palmitic (9.7%) and stearic (4.6%). Poison: Roots, stems and leaves contain hydrocyanic acid. Medicine: A decoction of the bark is used against diarrhoea and abdominal pains. A leaf poultice is used to relief malarial fever and is applied on cracked feet. A preparation from dried leaves, known as banaba, is widely used in the Philippines to treat diabetes and urinary problems.