‘Concretisation, low water table to blame for tree falls’

Kolkata: Two back to back nor'westers on Sunday and Monday that uprooted over 40 full-grown trees, nearly all of them in south Kolkata, is yet another pointer to the peril of rampant concretisation and depletion of the water table in the south.According to a Kolkata Municipal Corporation parks dept official, areas like Alipore, New Alipore, Behala, Tollygunge, Jadavpur, Lake Road and Southern Avenue recorded loss of greenery as the majority of the uprooted trees were removed from these areas. "We noticed that the roots of several trees that collapsed had been weakened due to concretisation of roots. We need to take special care of such types of trees to prevent more loss," said a civic official. The KMC official added that the civic body would deploy extra manpower at the boroughs, keeping in mind the possibility of squalls in the next few weeks.Speaking to TOI, environment activist Bonani Kakkar said paving of footpaths in a manner that did not leave any breathing space for tree trunks effectively denied water and nourishment to roots and made trees vulnerable."This concretisation spree in the past decade and a half has led to trees getting uprooted every monsoon. While paving, even roots that surface on the ground are chopped off. It is effectively a slow murder of trees that take 35-40 years to grow," said Kakkar.She also pointed to the need for selecting the right species of trees for avenue plantation. "Trees like gulmohar easily suffer damage. We need a balance of resilient trees that add seasonal colours, offer shade and grow fruits," she said.Naturalist Arjan Basu Roy also highlighted lopsided pruning of the crown that altered the natural balance of trees, causing toppling during storms like nor'westers. "When the head load is pruned on one side alone, it shifts the centre of gravity of the tree and makes it prone to toppling during a storm," he explained.Basu Roy also said it was extremely important for the civic body to replace the space vacated by a tree that had fallen with another tree and not hawkers, sculptures or a place of worship. "We have to protect the space and make it green again," he said.