I feel a bit stupid for not having recorded this long long ago considering how strongly I feel about it but nevertheless.
So let me state the position very clearly. The Peltophorum tree is the most common tree in Mumbai today. It has been the favourite in plantation drives by the municipal corporation over the years. But peltophorum is not a good tree to plant and Mumbai should take steps to discontinue planting the peltophorum. Here is why:
The first two are the principal guiding points and the others derive from these and especially from point two.
1) Trees are long terms investments. Trees last for 30-50 years and even more. Just as there are lock-in features in a number of other investments like financial product, an educational degree you may choose or a career decision similarly in the case of trees it is difficult/almost impossible to reverse a decision after planting and nurturing a tree for a while.
2) While planting a tree you have to be really (and I mean really) greedy. Following from point one when you are investing in a financial product or an education or career you are looking at maximising your investment on a number of accounts income, self-fulfillment, happiness of others. But to be greedy you need to be intelligent and know your trees well.
Things to be greedy for in trees.
What is the primary reason why trees are planted for? Shade? Yes, shade is the primary reason why trees are planted. But then there are a number of trees which give shade. You have to look at a few things besides just shade when planting trees.
1) Is it a native or a non-native tree? This is the most important consideration and if you get this right then in most cases you would have secured a long term worthwhile investment. If a tree has been part of the Indian geographical region and more specifically of the region in which your city is located then over millions of years the tree has acquired properties which makes it a very natural part of the local climate and other factors. Trees like peltophorum, Gulmohur, Rain tree are trees which have been around in India only fairly recently, extending to about three hundred years. Three hundred years is absolutely nothing when considering geological time – the time for which the earth and various plant and animal forms have been around. In three hundred years these trees have not intermingled with local birds, diseases, pests, pollinating factors etc.
The recent epidemic scale infestation of rain trees by the mealy bug is a good example of how decades of efforts can be laid to waste if the right tree species is not chosen. Till even a year ago nobody could have imagined that the tall, strong and such huge shade giving rain trees could be reduced to absolute dust by a teeny-weeny bug. We have no idea if going in the future there will be an infection or a bug which will solely target the peltophorum tree.While it is still to be conclusively proven some of us are speculating whether the mealy bug epidemic suffered by the rain trees could be a result of climate change? And if that is the case we need to be very careful for the coming years.
When it is a long term investment it pays to look into what can happen a few years hence.
2) When considering other factors, the most important one is whether the tree supports other associated species like birds and butterflies? When you are going to have a tree around for more than 30 years it is good to have a tree which attracts different kinds of birds and butterflies to feast on nectar or fruits that the tree provides.
Where I stay – I am on the third floor – I am lucky to receive a line of coconut palm trees which have reached to roughly the same height over a few years. And boy what a feast for the senses that is! The coconut palm flowers attract a great variety of birds and in the case of my palms all are available for viewing at an eye level. Purple sunbirds, bulbuls, Magpie Robin, Tickels Flowerpecker, a common kingfisher is the latest addition. All these birds add a lot of colour, melody and engagement with the tree. Right below is a slow growing and short guava tree which supports parakeets and an occasional coppersmith (call here)besides some of the ones on the palms. There is a banyan tree in one corner of the garden and that provides abundant berries.
In cases of the peltophorum, the trees flowers and fruit are not attractive to a single bird or butterfly species. If you were to stand for long in the presence of a peltophorum tree you realise what a silent, friendless, lifeless tree it is. You feel a bit sad about the tree as well about the whole idea of planting such a tree in the first place.
A few pics from what I get to see from the third floor.
3) Another factor which makes peltophorum a bad choice for Mumbai is leaf fall. Lets be very clear that there is a difference between a tree in an urban area and one in a forest. A forest floor has the luxury of accepting any amount of leaf litter. The same cannot be the case for an urban road or compound. Look at my favourite trees again – the lagestromium sheds leaves only once in a year sometime around December.Another favourite, the karanj is an absolute darling! This is almost evergreen or semi-deciduous and so very little leaf fall.
What about the peltophorum? Whole year! Yes the whole year the tree will keep shedding its tiny leaves. If a road, which has peltophorum trees is left unswept for a few days there will be a heap of fallen leaves below it. It is a troubling sight for me to see the municipal sweepers having to labour so much to collect all the leaf fall. And then many times disposing it can be so much of a pain that it is burnt in small heaps adding to pollution.
4) Local context is extremely important while planting trees. As an absolute simple example you cannot plant a tree with a very wide canopy in a narrow road and it would be waste to plant a short crown tree on a wide tree. There can be other factors like nature of habitation around, garden or road side, presence of absence of utilities under the surface and more. In the absence of context sensitive planting you can be left with a tree which can be a nuisance at times.
5) Beauty can be subjective but you need to know trees to realise how there are some trees out there which are so much more beautiful than the peltophorum and deserve to be planted on this point alone. Below are photos from the flowering Amaltas. The sight of these flowers can never be compared by a peltophorum, which can at times be so celebrated. The flowers of Amaltas are an absolute delight and a celebration. The other great advantage with the Amaltas is that it is tree of extremely modest proportions, which completely suits an urban agenda.
Karanj has one of the most beautiful green shade in its foliage compared to the darkish green, dead complexion foliage of the peltophorum
My top favourites are as below. In separate entries I will speak about what I like so much about these trees. I would strongly recommend planting of these trees where a rain tree has been left unrecoverable from the mealy bug infestation.
Jarul/Taman (common local name), Lagestromia speciosa or Queens Flower. This is also the State Flower of Maharashtra
Karanj, Pongamia pinnata
Amaltas, Cassia fistula
People can only go ooh and aah on seeing the yellow flowers of peltophorum till they have not seen the Amaltas tree.
Kadam, Neolamarckia cadamba
If you agree with the points in this post and feel that peltophorum plantation should be discontinued and the trees mentioned above – and some more – should be given a prominence then please do comment on this post and also write to the MCGM, Chairman, Tree Authority. every comment and letter to the MCGM strengthens the efforts. You can help achieve a better quality of tree cover for Mumbai.