Explained: What it takes to transplant a full-grown tree

Transplanted trees in general have a poor survival rate. Of the 16,461 trees that have been transplanted in Delhi over the past three years, only 5,487 — a third — survived, data show.

According to the Delhi government’s Tree Transplantation Policy notified in 2020, “The benchmark tree survival rate at the end of one year of tree transplantation shall be 80% or as notified by the department, from time to time.”

What does transplantation mean?

Three years ago, the Delhi government had announced, as part of its Budget, that of all the trees that were required to be cut for any project, permission (after due process) would be given only for a maximum of 20% — and the rest would have to be “transplanted”, either on site or elsewhere.

The transplantation of full-grown trees first came into public consciousness in Delhi when, in 2011, the voluntary organisation Green Circle helped remove five mulsari trees that were growing in front of the Bada Gumbad in Lodhi Garden. These trees were relocated inside the garden.

Since then, several businesses offering professional tree transplantation services have come into existence. As part of the tree transplantation policy, a tree transplantation cell has been created in the Delhi government’s Forest Department. The Forest Department has started a process of empanelling companies that have the expertise to carry out the transplantation of trees.

Is it even possible to transplant a full grown tree?

Experts say that even in theory, transplantation of trees is a complex and delicate process whose outcome cannot be predicted. Speaking to The Indian Express earlier, ecologist Dr C R Babu had underlined that transplantation requires time, patience and expertise.

“The survival of transplants depends on the type of species. If they are shallow-rooted plants, there will be greater success. Some transplanted trees are highly sensitive and die because they are unable to adjust to the shock of transplantation,” Dr Babu said.

The age of the tree is also important, he said. “If you have a 10-15-year-old tree where the root system is still shallow, the tree might survive. Transplanted trees can take 10-15 years to develop a full-fledged tree canopy that renders ecological service.”

Transplanted trees are also more susceptible to abiotic and biotic stress, Dr Babu said, and to termite infestation. “Young, growing plants are more immune and tolerant to such stressors. All this taken together, the success rate of transplantation is low.”

Navneet Srivastava, Deputy Conservator of Forests (West), told The Indian Express this week: “It (transplantation) is a technical subject, and some trees that are being transplanted are 70-80 years old. Sometimes user agencies transplant trees and then abandon them. Monitoring was difficult, but it has now been intensified… Transplantation has many phases and the tree needs care to survive the shock of transplantation.”

What are the steps involved in transplanting a tree?

Transplanting a tree is not the same as uprooting it and placing it in a pit that has been dug elsewhere. The process involves multiple steps and requires significant expertise.

First, the soil around the tree is dug up to isolate the roots. The big branches are lopped off, leaving only small shoots for regeneration. This is done to make transportation of the tree to the new location easier.

The root system is covered with wet gunny bags to protect the roots and to keep the tree hydrated. The tree has to be first sent to a nursery to acclimatise to a new kind of soil, and to regenerate. Once new shoots start sprouting, the tree is lowered into a pit created in its new spot.

Can any tree be transplanted?

Not all trees can be transplanted. While peepal, ficus/ fig, semal/ silk cotton/ bombax, and sheesham/ Indian rosewood are tolerant to transplantation, trees such as dak/ palash/ tesu, arjun, shahtoot/ mulberry, and jhilmil are not.

In general, any tree that has a tap root system cannot be transplanted, as the root goes deep into the soil, and it is not possible to isolate it without damage.

A Forest Department official told The Indian Express that transplanting any tree with a trunk girth of more than 80-90 cm is not advisable as the tree cannot bear the shock, and will eventually die. That effectively means that big, old trees cannot, in most cases, be removed to another location.

Also, it is critical to consider soil type before transplantation. A tree growing in, say, the Delhi Ridge will not easily acclimatise to soil in the Yamuna floodplain, as the two ecosystems are entirely different.

How expensive is transplantation?

Dr Babu, who was part of a team that had transplanted peepal and ficus trees from Delhi University a few years ago, said the process had cost Rs 1 lakh.

Delhi Forest Department officials had told The Indian Express earlier that the cost of transplanting an average-sized tree might come to around Rs 1 lakh, which included post-transplantation care. For larger trees, the cost could go up to Rs 3 lakh.

Private and voluntary organisations, however, claim that the cost is between Rs 5,000 and Rs 10,000 per tree.