Common name: Pongamia Pinnata, Indian beech tree, Honge, Pongam oiltree
A very common tree on Indian roads, especially in South India; the Honge tree has many industrial and medicinal uses. These trees can grow to a height of 15-25 meters and spread around giving ample shade. The trees start flowering after 3-4 years, producing beautiful, fragrant flowers with a purple calyx; white and pink petals.
The flowers grow on spike-like racemes in multiple layers, the lower layers blooming first and then the upper layers, like the peacock flower trees. The flowers then form green seed pods that turn brown when they mature, and contain 1 or 2 brownish-red seeds. The pods do not open to disperse the seeds; they need to fall to the ground and decompose for new plants to sprout.
Indian beech trees are tolerant to drought, pollution and heat, and quite hardy; making them ideal for the Indian climate. The seeds and leaves have some amount of toxin, but also has many uses. The seeds are used in bio-diesel production. The oil obtained from seeds, called pongamia oil is used as a lubricant, fuel, and also in cosmetics. The residual cakes obtained after extracting oil, is used as a fertilizer and as livestock feed.
The oil also has antiseptic and pesticidal properties. A very common characteristic of Indian beech tree is the formation leaf galls, which are excessive growths that happens on leaves in response to foreign organisms like bacteria, virus, fungi etc. These leaf galls disfigure the leaves with unsightly warts, curling up the leaves. But the tree remains healthy and productive.
Propagation is from seeds or stem cuttings.