There is some disagreement as to the correct name for this species, with Millettia pinnata (L.) Panigrahi (treated here as a synonym) being accepted as correct by some botanists.
Cajum pinnatum (L.) Kuntze
Cytisus pinnatus L.
Dalbergia arborea Willd.
Derris indica (Lam.) Benn.
Galedupa indica Lam.
Galedupa pinnata (L.) Taub.
Galedupa pungum J.G.Gmel.
Millettia novo-guineensis Kaneh. & Hatus.
Millettia pinnata (L.) Panigrahi
Pongamia glabra Vent.
Pongamia mitis (L.) Kurz
Pongamia xerocarpa Hassk.
Pterocarpus flavus Lour.
Robinia mitis L.
Common Name: Pongam
Pongamia pinnata is a fast-growing, medium-sized, evergreen or briefly deciduous, glabrous shrub or tree with a broad crown of spreading or drooping branches[
]. It usually grows 15 - 25 metres tall, with a straight or crooked bole 50 - 80 cm or more in diameter[
A multipurpose tree, it is particularly valued for its oil and also supplies dyestuff, wood, fuel, insect repellent, medicines and various other commodities. The tree is planted in the humid tropical and subtropical lowlands around the world as a pioneer and soil reclamation plant[
]. This species is one of the few nitrogen-fixing trees to produce seeds containing oil, and these are collected in vast amounts in India for commercial processing of industrial uses[
The tree is often planted in homesteads as an ornamental tree and in avenue plantings, roadsides, and along stream and canal banks[
]. However the large amounts of flowers, leaves and pods that it regularly sheds make it not very suitable for this purpose[
The seeds are poisonous[
]. Pounded and roasted seeds used to be utilized as fish poison[
E. Asia - Indian subcontinent, through south-east Asia to north-eastern Australia, Fiji and Japan.
Occurs naturally in lowland forest on limestone and rocky coral outcrops on the coast, along the edges of mangrove forest and along tidal streams and rivers, often with its roots in fresh or saltwater[
|Other Uses Rating||
|Cultivation Status||Cultivated, Ornamental, Wild
Native to humid tropical and subtropical environments, it is found at elevations from sea level to 1,200 metres[
]. It grows in areas where the mean annual temperature ranges from a minimum of 1 - 16°c, up to a maximum of 27 - 38 (exceptionally 50)°c, and the mean annual rainfall is 500 - 2,500 mm, with a dry season of 2 - 6 months[
]. Mature plants can tolerate light frosts[
The plant can grow on most soil types[
]. The best growth is found on deep well-drained sandy loams with assured moisture, but it will also grow on sandy soils and heavy swelling clay soils[
]. It does not do well on dry sands, although it tolerates saline conditions, alkalinity and waterlogged soils[
]. Tolerant of shade, it can grow under the shade of other trees, but will also grow well in full sun[
]. Established plants are drought resistant[
]. Plants are wind-resistant, tolerating at least some salt-laden air[
]. Plants become nutrient deficient if growing in soils with a pH higher than 7.5[
The plant has a long, thick taproot and widely spreading lateral roots[
]. The spread of roots on this species, about 9 metres in 18 years, is greater than most other species; moreover it produces root suckers profusely[
]. Because of these characteristics, pongam is unsuitable for agroforestry and has the potential to become a weed if not managed carefully[
Pod production commences when seedlings are 5 - 7 years old[
]. The pods do not open naturally, and must decay before the seeds can germinate[
Individual trees yield 9 - 90 kg of pods annually, while mature trees yield 8 - 24 kg of seeds annually[
Growth of young trees is fairly slow; a growth of 1.3 metres in height and 0.4 cm in diameter in 13 months was recorded in India[
Trees coppice well and can also be pollarded[
When planted as a shade or ornamental tree, pruning may be necessary to obtain a trunk of appropriate height[
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[
The seed oil is given as a stomachic and cholagogue in the treatment of dyspepsia and cases of sluggish liver[
It is used externally as a liniment for rubbing on skin diseases and rheumatic joints[
]. It has been shown to be effective in enhancing the pigmentation of skin affected by leucoderma or scabies[
The powdered seed is given as an expectorant in the treatment of bronchitis and whooping cough, and is also prescribed as a febrifuge and tonic[
A paste made from the powdered seed is spread on sores and rheumatic joints[
An infusion of the leaves is used to relieve rheumatism[
]. A decoction is used as a cough remedy[
The leaves are crushed and applied as a poultice for the treatment of parasitic skin diseases and to relieve bleeding haemorrhoids[
].The expressed juice is used on herpes and itches[
The flowers are claimed to have anti-diabetic action[
The fresh stem bark is astringent and is taken internally to relieve bleeding haemorrhoids[
]. It is also applied to reduce the enlargement of the spleen[
The root bark contains a bitter alkaloid and is used as an abortifacient[
The antiseptic root juice is put on sores and ulcers and used to clean teeth[
Because of its extensive network of lateral roots, and its ability to fix atmospheric nitrogen, this is a preferred species for controlling soil erosion and binding sand dunes[
Because it tolerates moderate levels of salinity, it is an ideal candidate for recovering a variety of wastelands such as saline soil reclamation[
]. It is also used in reforestation of marginal land[
Grass grows normally beneath the tree so it has been planted to provide shade in pastures. It is also grown as a windbreak and shade provider for tea plantations in Sri Lanka[
The incorporation of leaves and the presscake into soils improves fertility[
]. Decomposed flowers are valued in the tropics as rich nutrition for special plants, especially when grown in greenhouses[
]. The leafy twigs are used for green manuring rice paddies, sugarcane fields and coffee plantations[
The tree is used as a host for the hemiparasitic sandalwood, Santalum album[
The seed contains 27 - 40% of a thick, yellow or reddish-brown oil[
]. The oil has a bitter taste, a disagreeable aroma and a specific gravity of 0.9371 at 15°c[
]. It is used as a lubricant, varnish, water-paint binder and in soap making[
]. The seed oil was formerly indispensable as an illuminant in lamps, but has been largely replaced by kerosene[
]. Two kilos of mature pods will yield about 1 kilo of husked kernels. Extracted oil amounts to 13.4% of the whole seed pod; 26.97% of the kernels[
The presscake, when applied to the soil, is valued as a pesticide, particularly against nematodes[
In rural areas, the dried leaves are stored with grain to repel insects[
The bark fibre is made into string, twine or rope[
The roots yield a natural pigment called 'pinnatin'[
The wood ash is employed in dyeing[
The wood varies from white to yellowish-grey with no distinct heartwood[
]. It is beautifully grained and medium to coarse textured[
]. Although it is a moderately strong timber that is relatively easy to saw, turn and finish, the wood is not considered a quality timber because it is not durable, tends to split and warp during seasoning and is susceptible to insect attack[
]. It is used for cabinet making, cartwheels, posts, agricultural implements, tool handles and combs[
]. It is also suitable as a source of pulp for paper making[
With a calorific value of 4 600 kcal/kg, pongam is commonly used as a fuel wood[
Seed - requires no pre-treatment. The seed is usually sown in situ, germinating within 1 - 5 weeks of sowing[
]. Germination is hypogeal and the radicle develops quickly before the plumule emerges[
]. If sown in a nursery bed, the seed can be planted at a close spacing, as young plants tolerate shade well - a spacing of 7.5 x 15 cm is recommended[
]. Seedlings attain a height of 25 - 30 cm in their first growing season[
]. Transplanting to the field should occur at the beginning of the next rainy season when seedlings are about 60 cm in height[
]. Seedlings have large root systems and soil should be retained around the roots during transplanting[
Seed storage behaviour is orthodox and seeds remain viable for about a year when stored in air-tight containers[
Natural reproduction is profuse by seed and common by root suckers[
]. Spontaneous seedlings and root suckers are produced and may cause serious weed problems[
Stump cuttings of 1 - 2 cm root-collar diameter[