BMC’s tree pruning notice may harm tree health: Experts

The BMC has issued notices to 3,500 housing societies to prune trees, but, in the absence of guidelines, the pruning will not be scientific, say experts

The BMC has issued notices to 3,500 housing societies to scientifically prune trees. In the absence of guidelines and a panel of tree experts including arborists, however, the pruning will not be scientific and will prove detrimental to tree health, say experts.

Mumbai, India - July 25, 2017: Municipal corporation cuts down branches of a tree at Colaba in Mumbai, India, on Tuesday, July 25, 2017. (Photo by Nilofer Khan/ HT)

Vaibhav Raje, arborist, Treecotech LLP, a landscape and arboriculture consultancy, said a risk assessment must be done before cutting trees, “One cannot randomly go and start pruning trees. Based on the condition of trees we can recommend what type of pruning is needed. Just like how doctors assess patients, arborists assess. They find out how structurally weak or strong the tree is, the physiological problems present, and the remedial or mitigation measures to be taken. Pruning is one of the mitigation measures. It is not the ultimate measure.”

Based on an annual risk assessment, the arborist can find out low- and high-risk trees in urban and rural flora. “Then there should be a strategy for urban tree management. But now the BMC uses an unqualified contractor. The labourer goes with an axe and removes all the branches without knowing what should be the percentage of crown and canopy reduction. They randomly hack trees. There is no system to it. For instance, they just cut 10cm across without any assessment,” said Raje.

The pruning needs vary depending on species. Therefore, a blanket approach cannot be taken for all trees.

An arborist may charge ₹25,000 to ₹30,000 per tree a year for scientific tree maintenance including any pruning required. But eventually this pays off in terms of maintaining tree health and cover. Also the actual pruning required will be less than if it were to be done unscientifically for multiple trees.

Raje said that depending upon the number of trees, site conditions and the size of the tree, the cost varies anywhere between ₹5,000 - ₹15,000. A coconut tree will take less time for pruning than a badam tree and the rates will vary depending on time invested. “Whether we need to use the rope axis or a cherry picker crane to prune are the factors which decide the cost. There is no blanket rate,” added Raje.

In the wake of the notices to the housing societies for tree pruning, Makarand Narwekar, former BJP corporator from Colaba, has written to the BMC demanding that the civic body must draft guidelines on tree pruning and appoint a panel of experts including arborist and expert tree pruning agencies on the lines of agencies empaneled for fire audits.

Narwekar said that this will not only avoid the fatal incidents due to tree fall but will also help in saving the city’s green cover. “These notices are unlikely to yield visible and concrete results in the absence of empanelment of arborists, tree pruning agencies or experts. The BMC itself carries out the tree pruning based on just visual inspection of trees. Then, how can it expect the citizens to carry out tree pruning scientifically? It has been revealed in the past that the trees have been cut under the garb of tree pruning which is a serious cause of concern,” said Narwekar.

He further demanded that the civic body must immediately draft guidelines for the general public on how the tree pruning should be carried out scientifically. “The BMC must empanel experts in tree pruning on the lines of empanelment of agencies for fire audits in housing societies. That will enable the housing societies do tree pruning scientifically. Issuing notices to housing societies for tree trimming holds them accountable, but doesn’t ensure scientific pruning which is important to avoid fatal tree fall incidents in the city,” added Narwekar.

Narwekar further claimed that the civic body has engaged agencies which claim to be experts in tree cutting and pruning, but they are not.

“Appointment of contractors without domain knowledge is leading to the death of precious trees in the city. Contractors having a background in desilting and transport companies are damaging Mumbai’s tree cover in the name of tree trimming and pruning,” added Narwekar.