The Indian Frankincense Tree

Salai (Boswellia Serrata/सालय, सालई) is a moderate-sized deciduous tree with a light, spreading crown and somewhat drooping branches. The tree has high ornamental value. It is popular for avenue planting in India.

The Salai tree has beautiful flowers. But what is more attractive is its bark or that’s what makes the tree easily identifiable. The bark is very thin, greyish-green, ashy or reddish with a chlorophyll layer beneath the thin outer layer, which peels off in thin, papery flakes. It gives a unique and attractive appearance to the tree. Leaves are alternate, crowded towards the ends of the branches; and very variable in size. 

The tree yields a yellowish-green gum-oleoresin known as ‘salai guggal' from the bark. It is known to be a good substitute for imported Canada balsam. Medicinally, the salai guggal gum is used as a diaphoretic and astringent. It has potent analgesic and anti-inflammatory effects that can reduce the pain and inflammation of joints. Salai have been clinically studied for osteoarthritis and joint function. It is also tapped for resin which is used as incense, hence is also known as Indian Frankincense tree.

It has been recorded as a new lac host species. It is a suitable species for afforestation on poorer soils in areas of dry sandstone hills which have been denuded of vegetation. Under such circumstances, its ability to withstand the adverse effects of forest fires, its immunity to being browsed or lopped for fodder, and its power of resisting the effects of insolation & drought are great assets. 

Salai can be propagated fairly well from seeds. Mature seeds should be immersed in water before they are sown, to separate out the sterile pyrenes, which float on the surface. Usually seed germination takes a week or two. It also has the remarkable ability to sprout from large branch cuttings or root suckers.

The tree has the ability to thrive in the poorest and the shallowest soils where most of its associates remain stunted. It is characteristically found on the slopes & rocky ridges of hills, as well as on flat terrain, attaining a larger size on fertile soils. It is resistant to drought and resists fire better than other species in its zone of occurrence. It is also frost hardy and serves as a nurse tree for other species.