A banyan tree is often called a micro-forest

Have you ever desired to have India’s national tree planted in your courtyard? While there will be great objection to having a national animal or bird at home, certainly there will be great appreciation for a National Tree in your garden. The mighty banyan is the designated national tree of India. The idea of planting banyan could be considered a wrong choice in urban gardens. Why would any landscapist recommend this outsized and expansive species which is a total misfit in cities with rapidly shrinking green spaces?

For those who have grown up in metros and concrete jungles, the name banyan would mean a large, sprawling tree in a rural setup where local panchayats take place for the dispensation of justice. This is the imagery that is more often portrayed in movies.

Ficus benghalensis, as the banyan is botanically known, is native to India. The specific name benghalensis, commemorates Bengal, where the venerated great banyan grows inside the Acharya Jagadish Chandra Bose Indian Botanic Garden at Kolkata. Banyan takes the name from the Sanskrit word banias which literally means traders. Since they sold their merchandise under the shade of this tree during the colonial period, the tree was christened as banyan by the British.

Aerial roots

Banyan requires a lot of space around it. The most striking feature of this tree is the strong, aerial roots which hang in clusters from the upper parts of the branches. It reaches the ground much below from its source of origin turning into a great pillar of strength and as an accessory trunk. Therefore, the tree actually appears like an agglomerate of many trees. Sometimes the aerial roots are tightly knitted and knotted, looking haggard which probably prompted Rabindranath Tagore to write the lines ‘O you shaggy-headed banyan tree standing on the bank of the pond…’

Though it is a deciduous tree, the period of its leaf fall is not conspicuous and therefore the tree renders the appearance of an evergreen species. It is a shade yielding tree and offers a great respite during summer because of its intact foliage during that time. There is a rapid decline in banyan population in cities because of rampant urbanisation. Moreover, people in cities prefer small ornamental trees that would occupy very minimal space in the garden. But fortunately, in Chennai few hundreds of this large species have escaped the fury of urbanisation and are concentrated within the safe portals of IIT-Madras, Guindy National park and Raj Bhavan. The most famous banyan in Chennai is the one inside Theosophical Society which attracts a stream of visitors from various parts of the nation and the world. Ironically, both the famous trees, that is, the one in Theosophical Society and the one in Kolkata Botanical garden have lost their hoary, mother trunk during a severe squall few years ago.

Banyan is celebrated as a sacred tree and is not axed because of the popular belief that it brings prosperity and goodness to the neighbourhood. Banyan trees that are many years old are considered as heritage specimens that deserve protection from vandalism and massacre.

Pollination

Though banyan is a high and mighty species, it is obligatorily dependent on most humble and unobtrusive organisms for its two survival processes - pollination and dispersal. Pollination is facilitated by the tiny fig wasps and dispersal of seeds is made possible by frugivorous birds and bats. The fruits of banyan, popularly known by the name figs, are actually a congregation of tiny flowers inside a receptacle, known as a hypanthodium.

There is a very intricate, obligate and a mutualistic relationship where the fig gets pollinated by the wasps and the figs provide a safe niche and food for wasps and their young ones.

Keystone species

A single banyan tree can be allegorically referred as a micro-forest, since it supports a variety of wildlife like birds, wasps, bats and therefore is labelled as a Keystone species. Banyan sustains many a wild life by offering food, shelter and shade. Closely observing the flurry of activities in the banyan tree during fruiting season is an exciting experience by itself, especially for children who are passionate about recording facts for their assignment in natural science. For certain, they will not be able to contain their surprise as it is clearly unequivocal to any classroom or book experience.

Banyan tree has been recorded in the Guinness Book of Records for being the widest tree in plant kingdom. Alandur in Chennai commemorates Aalamaram, the Tamil name for banyan which was widely prevalent in that area. The bonsai of banyan is quite popular because of its easily amenable nature and is a ready choice for bonsai gardens.

Is it possible to grow a banyan in your home garden? Yes, if you are in a house with a lot of open space or working in an organisation that encourages tree planting. Banyan saplings are available in plant nurseries.

The writer is a botanist and Assistant Professor, Department of Plant Biology, Women's Christian College.