From Arauco to Bangalore

It is a welcome move that the Karnataka Biodiversity Board has recommended ten trees to be declared heritage trees in the State. Recent reports bring to attention that all are old trees, ranging from 130 years to nearly nine centuries old. But one begins to wonder why it is just ten.

One of these trees is the tall araucaria cooki near the Band Stand in Lalbagh. It is an extremely tall tree which no one going to Lalbagh will fail to notice.

It looks as if this has been selected merely for its extreme height. Lalbagh had six species of araucaria (five visible now) and one species of related Agathis belonging to the same family. I have never gotten to see araucaria rulei in Lalbagh though I’ve been a visitor to the gardens for quite a few decades now.

The other tree in the heritage list from Bangalore, the Big Banyan tree (at Ketohalli ) is one of the largest and oldest in the region (said to be 400 years old).

Banyans are very offbeat in the ecological sense that they almost bear fruit right through the year, supporting a myriad of birds and mammals which feed on them, as also their pollinator wasps. In this they are much less seasonal than many other kinds of fruit-bearing trees. Figs in general are also unique in that each species is pollinated by its own dedicated species of wasp.  

From Arauco in central Chile
The araucarias are a group of tropical pines from the Australasian biogeographical region and the name itself is derived from Arauco, a region in central Chile where the araucani “Indians” live. Araucaria cooki (now called A. columnaris) is the Cook’s Araucaria or Coral Reef Araucaria from New Caledonia, A. excelsa (now called A. heterophylla) is the Norfolk Island Pine from the islands of that name, A. bidwilli is the Monkey Puzzle Tree and A. cunninghamii is the Moreton Bay Pine, both from Queensland,  Australia. The Monkey-Puzzle name is because the prickly, tangled branches would probably make a climb for a monkey very painful.

Fossil evidence indicates that ancestral Araucaria forests resembling this tree date back to the age of dinosaurs.

It has been suggested that the tree’s armour of dagger-like leaves was evolved to discourage enormous South American herbivorous dinosaurs, such as Argentinosaurus weighing an estimated 80 to 100 tons, from feeding on them! The only large Agathis in Lalbagh is south of the statue. In nature, the range of the genus Agathis is from Peninsular Malaysia to New Zealand. From a conservation point of view, A. heterophylla and A. rulei are termed vulnerable and endangered respectively in its native habitat.
Most people think of the temperate regions when they think of pines. But these are tropical pines which continued to survive in the original climates this whole group of gymnosperms evolved from.

From an ecological and botanical perspective, they are important, and go to form the “emergent” layer from the canopy of the forests they are part of.The question which comes to mind is on what basis were these trees selected for a heritage list? 

Do we consider this a beginning to earmark individual trees for a special consideration or do we look at this list as an ad hoc exercise? Size obviously has been an important factor. But does this mean we disregard all other criteria?