An old eucalyptus, and the ground below
An old eucalyptus, and the ground below, playing host to a range of moss, fungi and plant life (Photos: Jacob Cherian)

How Nature Can Occasionally Beat Human Interference

In the 1820s, when the British started exploring the beautiful and unique areas of the Western Ghats, the vegetation patterns―particularly in the Nilgiris and Palanis―were thought to be bizarre. The entire region was covered with tropical montane forests or sholas in the valleys, with vast stretches of grassland all around and streams, marshes, and water bodies criss-crossing throughout the region.

This pattern had obviously existed for thousands of years, but was not thought to be natural as it was assumed the grasslands would be farmed for agricultural use. Of course, the first idea of those arriving to live in the area, without any understanding, was to plant trees and plants which were totally unsuitable and exotic: a disaster for any endemic floristic areas. 

This resulted in a devastating impact on indigenous vegetation; the loss of grasslands around the sholas due to poor farming techniques, for example, and the spread  of plants that are nitrogen producers such as acacias— nitrogen being a disaster for the original grassland plants. In the Western Ghats, various acacia species (commonly known as wattle), which have also been introduced from Australia, have the most devastating effect on open grassland areas. It has been estimated this year that only about eight percent of grassland still exists in the Palanis.  

I arrived in Kodaikanal in 1984; by that time commercial plantations or monocultures had been introduced into many parts of the Western Ghats for over 100 years, causing enormous damage to the natural ecosystems. Around that time, many environmentalists consistently questioned the original form of vegetation in the upper Western Ghats and whether it had been sholas, grasslands, or  water bodies. They got together with scientists from several well-known institutes, including the French Institute in Pondicherry, and decided to  try to discover how old the vegetation was using palynology: the study of plant pollen spores and microscopic plankton. 

The French Institute, until now, has a department dealing specifically with this very precise work. The palynologists spent many months in the mid-1980s digging into the rock face under the soil, and extracting pollen samples. This proved beyond doubt that the original types of vegetation had persisted for over 35,000 years. Although most of the work was done on grasslands, some sholas were included. It was an eye-opener for many, but not for those in the commercial sector; which led to a continuing rise in the planting of exotics, to the detriment of the natural ecosystems.

Having hiked consistently in the Western Ghats for 35 years and being British by birth, I am ashamed of the ignorance of foreigners who came, for whatever reason, to live in this area and made a living while ignoring their impact on  the natural environment around them. 

Eucalyptus globulus
Eucalyptus globulus (Photo: Ian Brooker and David)

Eucalyptus, particularly blue gum or Eucalyptus globulus from Australia and Tasmania, was introduced to the Palanis in 1843 by Major JM Partridge of the Indian army. Historically, Major Partridge was also responsible for naming a shola. In 1852 he and his men camped on the eastern edge of the forest; the major thus thought it his right to name the area Bombay Shola, simply because he was from Bombay, which has remained its name ever since.

He planted eucalyptus as the tree is known to absorb large quantities of water and would help reduce insects, and contain the large areas of marsh land, particularly in the Shenbaganur area. 

This was the start of a flood of other eucalyptus species throughout the Palanis as other uses were found for the trees, such as the extraction of eucalyptus oil. From the time I arrived in Kodai, I was told by everyone that the tree was either a commercial success or a disaster. I tended towards the latter view, but have since changed my mind. (Interestingly, in Munnar and some other tea-growing areas Eucalyptus grandis is grown for the wood, which is used in furnaces to prepare tea. I am presuming that this is still the case.) 

In 2004, Father KM Mathew, the renowned botanist and founder of the Palani Hills Conservation Council, sent me a note about the work he was doing on the growth of eucalyptus across decades. I have come to agree with him ever since. According to Mathew, the interesting thing about eucalyptus growth―and this applies to many of the species grown commercially in the Western Ghats―is that for the first seven years of development, they extract enormous amounts of water and nutrients from the soil; making it virtually impossible for other trees or plants to emerge. During the second seven years of growth there is a reduction in the amount of water and nutrients absorbed, and by the 14th year the tree has reached a stage of living within its means, so to speak. 

It is at this stage that a miracle can appear in the larger plantations: at this point the trees are large enough to protect new shola growth. It is a well-known fact that tropical montane forest species require continuous protection when young, to allow them to thrive.

Over the last ten years, it has been a wonderful revelation to see shola species slowly emerge between the eucalyptus trees and gradually grow in size. This is especially visible on the Ghat road below Perumalmalai, along the Addukam road, and down towards Thandikudi village. 

It is possible that once the shola trees grow up to the level of the eucalyptus, they will overpower them with their wider crowns and then the eucalyptus would die. Of course this will take time, but something to this effect would eventually enhance and enlarge sholas all over the Palanis and, perhaps, in other areas of the Western Ghats.

Sadly, amongst all the other commercial plantations in the Palanis and other areas of the Western Ghats, the eucalyptus species are the only ones that have shown a clear ability to help shola regeneration.

Shola forest and eucalyptus growing side-by-side
An example of a shola forest and eucalyptus growing side-by-side near Shenbaganur. (Source: Google Maps)

Pippa Mukherjee

Pippa Mukherjee is an experienced environmentalist and the author of Flora of the Southern Western Ghats and Palnis, Trees of India, and Common Trees of India. She is a Founder Member of The Palni Hills Conservation Council and has over thirty years of teaching experience, much of it spent at Kodaikanal International School. She lives in Pallangi, Kodaikanal.

Previous Story

Re-growing a Forest: The Remarkable Life of Suprabha Seshan and Her Rewilder Friends

Next Story

Editorial: Letter to the Readers of The Kodai Chronicle, October 2021