Methods of Creation

A living root bridge is formed by guiding the pliable roots of the Ficus elastica tree across a stream or river, and then allowing the roots to grow and strengthen over time until they can hold the weight of a human being. The young roots are sometimes tied or twisted together, and are often encouraged to combine with one another via the process of inosculation. As the Ficus elastica tree is well suited to anchoring itself to steep slopes and rocky surfaces, it is not difficult to encourage its roots to take hold on the opposite sides of river banks.

As they are made from living, growing, organisms, the useful lifespan of any given living root bridge is variable. It is thought that, under ideal conditions, a root bridge can last for many hundreds of years. As long as the tree from which it is formed remains healthy, the bridge will naturally self-renew and self-strengthen as its component roots grow thicker

A root bridge can be made in several ways:

1. Made By hand

A root bridge in Burma Village, East Khasi Hills, being developed without the aid of a scaffold.

Some living root bridges are created entirely by manipulating the roots of the Ficus elastica tree by hand, and without the aid of a scaffolding or any other natural or man made materials.

Often, locals using root bridges will make small alterations to them, manipulating young roots as the opportunity presents itself. Because of this, one can say that the development of a living root bridge is very much a social endeavor, and that the structures are perpetual works in progress.

Wood or bamboo scaffold

A root bridge being grown using a wood and bamboo scaffold. Rangthylliang, East Khasi Hills.

Root bridges are also commonly formed by training young Ficus elastica roots over scaffolds made from wood or bamboo, materials which are abundant in Northeast India. In these instances, the roots are wrapped around the outside of the perishable material. The scaffolds may be replaced many times over the years as the root bridge becomes stronger.

Areca Palm trunks

Here, a living root bridge is being developed with Ficus elastica strands being guided along a halved Areca Palm trunk.

Some living root bridges are grown by training young Ficus elastica roots through the hollowed-out trunks of Areca nut palms. The pliable tree roots are made to grow through betel tree trunks which have been placed across rivers and streams until the figs' roots attach themselves to the other side. The trunks serve to guide the roots, to protect them, and to provide them with nutrients as they decay. Sticks, stones, and other objects are used to stabilize the growing bridge This process can take up to 15 years to complete.This means of creating living root bridges can best be observed near the tourist friendly village of Nongriat.

Conventional structures

Here, Ficus elastica roots have been trained across a pre-existing steel bridge, in the hope that eventually, as the steel elements fail, the roots will form into a usable living root bridge.

Root bridges can also be trained by guiding the young roots of Ficus elastica trees across conventional structures, such as already existing steel wire suspension bridges.As the structure being used as a scaffold is already functional, the problem of the length of time it takes for a root bridge to become functional is here essentially bypassed; the conventional structure can be used until the more sustainable root bridge is sufficiently strong.