Experts question feasibility of tree transplantation for GNB Road Flyover project

Guwahati, Nov 7: Experts have expressed skepticism about the government’s plan to transplant trees along the iconic Dighalipukhuri for the construction of the GNB Road flyover, noting that the survival rate of transplanted trees is generally low.

The Forest Department previously attempted to relocate several trees uprooted during road widening and flyover construction on the Khanapara-Jalukbari highway, with mixed results.

"Around 45 trees were transplanted about two years back. Less than 30 have survived. The exercise couldn't be carried out further due to a lack of logistics. The girth of trees that were planted was less than 100 cm. We doubt there is scientific equipment to transplant such huge trees (with girth more than 200 cm) like those in Dighalipukhuri par,” sources, involved in the experiment, said, adding that the earlier effort also turned out to be a costly affair.

Studies have also indicated that the outcome of transplanting operations can be determined only three to five years after the procedure, and thus the actual success rate of the experimental exercise in Guwahati done two years back will be known much later.

Studies indicate that a tree over 20 to 30 years has a slower capacity to produce new roots, slower cell division and hormonal imbalance. A tree with a diameter greater than 1.2 metres may not be a successful transplant.

“Conditions of the trees to be transplanted including health, form and structure will affect the success of the proposed transplanting. Most trees cannot tolerate transplantation, particularly big old trees and the success rate is extremely low. There is no standard methodology in India for transplanting trees, even though some states have formulated policies in this regard,” a forest official told The Assam Tribune.

Root damage, improper creation of root balls and undesirable growing sites are some of the reasons that trees suffer from transplant shock, according to a paper by the University of Kentucky, College of Agriculture, which further states that the trees stressed from transplant shock are more susceptible to diseases such as thyronectria canker, a fungal disease that affects the branches of the tree.

Surveys point out that the survival percentage of trans- planted trees in India is not more than 50%. Only around 42.5% of the trees transplanted in and around Delhi, between 2019 and 2022, had survived, the survey further added.

Earlier on November 6, Chief Minister Himanta Biswa Sarma said that the government has now decided to construct the GNB Road flyover up to Rabindra Bhawan and the trees around Dighalipukhuri will not be impacted. One arm of the flyover will join the flyover from Lamb Road.

PWD officials, however, said a study is being done to shorten the flyover length in line with the government's decision and the final plan will be ready in a week. Visiting the under-construction flyover site last night, the Chief Minister claimed that the trees along Dighalipukhuri were “marked for transplanting and not chopping”. A similar argument was given by the Advocate General during the hearing of a PIL in the High Court yesterday.

-By Rituraj Borthakur