My article titled ‘Bengaluru needs its green cover to remain liveable’, led to questions about what can be done. A mission for re-greening Bengaluru is the need of the hour – a time-bound exercise with goals to be achieved. For example the goal could be to increase tree cover in Bengaluru by 20% in the next five years.

Step 1: Tree census

For starters, the government, that is the municipal administration – the Bruhat Bengaluru Mahanagara Palike (BBMP) must undertake a tree census to establish a baseline. Trees must be mapped employing qualified experts backed by technology such as a mapping tool and a mobile app for data entry. Every tree must be identified according to the species it belongs to, how old it is, the state of its health and its exact location and provided with a unique ID. This must be done ward wise. The exercise must include gated communities, institutions and public spaces within the urban agglomeration.

Step 2: Inferences from data

Once this data is tabulated, we will have a sense of the quality of tree cover with further details such as the diversity of species, whether the species is native or not, and whether they are invasive. With ward wise population we will be able to find out the number of trees per person in every ward. The data must be available on the website of the municipal corporation for access and verification by anyone at any time. This data can then be updated continuously and the current status at any point in time can be compared with the recommended tree cover per individual, giving us an important measure of the liveability of the city.

Step 3: Identification of planting sites

A simultaneous exercise is the identification of tree plantation sites. These must be geotagged as well. Trees can be planted in vacant public and private land, that must be set aside for the purpose, in parks, and on sidewalks every few metres. Strict adherence to guidelines is necessary in terms of green and open spaces in both institutions and residential projects, and the types of trees that must be planted.

Roadside trees, besides having all their regular advantages, also reduce pollution from vehicular traffic and provide a favourable microclimate all along the city’s street network. The difference in temperature on a stretch of road bereft of greenery and one that is covered by a shade of avenue trees can vary up to 4 to 5 degrees.

Step 4: Planting saplings

Next comes the actual planting of trees. A scientific approach to the selection of species and to the planting itself is vital. Here a cadre of trained gardeners recruited for the express purpose will help greatly.

Step 5: Taking care of trees

In parallel, we need to also work on preserving the trees that exist – this could mean nurturing trees that are still young and need looking after, treating trees that are diseased, replanting those that are not properly rooted and ensuring that there is adequate space around the roots for the percolation of water.

Tree committees in every ward

We don’t have to wait for government or the municipal authorities to take the initiative. A few private individuals have already started conducting tree censuses in a few wards of the city. Some tree plantation programmes are also undertaken every now and then. However the scale of the effort required is such that it cannot be left only to private individuals. In most cities around the world, citizens participate as volunteers in such exercises that are carried out by the municipal administration. The municipal administration has to be involved for a concerted and long-drawn effort such as this to bear fruit. Every ward must have a tree committee consisting of residents and municipal officials. The tree committee must oversee the plantation and upkeep of neighbourhood and street trees on a regular basis.

Such a mission has convergence with ground water conservation, disaster prevention, energy conservation, sustainability, biodiversity and clean air. There must exist several avenues for its funding. Moreover it gives back much more than it takes.

Quantifying damage from tree felling

On the other hand, every infrastructure project that demands the felling of trees must be able to quantify environmental advantages that will accrue in lieu of the environmental damage that the tree felling will cause. A case in point is the metro. Will building the metro lead to enough environmental advantages to justify a destruction of the city’s green cover? What are the alternatives? Are they better or worse for the environment? What will be the other collateral effects of a projects such as the metro? How long will it take to recover such a loss? What is the plan for compensation? The Environmental Impact Assessment (EIA) of the Bengaluru metro can be found on their website.

Only when we start thinking along these lines about every project big and small, will we be able to completely account for the environmental impact of our actions.

In sum, what we need is a change in our mind set, a change in behaviour. We need to look at trees not as roadblocks to development but as essential elements of civic infrastructure, much like we see the roads, water pipes and sewers.