Eucalyptus, commonly known as Nilgiri trees in Indian parlance is ubiquitously used for timber and oil.

It is a common experience for every person traveling across the Eucalyptus fields to experience a nasal stimulation of enhanced respiration, this is mainly due to the presence of the substance Eucalyptol (1,8-cineole) which is a mucus clearing agent.

Despite its exotic (ayurvedic) medicinal application this tree is very unpopular for its inimical nature.

Inflammable and invasive nature of Eucalyptus

Scientific cultivation of Eucalyptus beneficial for commercial farming — Image Source – Terrain.

In reality, Nilgiri trees can be considered a cursed gift of nature, while they are commercially beneficial to humans, the cost of a disaster is disproportionately large on the entire biosphere.

All weeds are generally invasive along with other kinds of detrimental features, but each feature shall be independent of the other,

for example, Parthenium is invasive and poisonous.

But the threatful features of this gigantic weed have confluenced to have a single outcome, that is to eliminate other species in its environment.

Due to the shading effect and strong root system of Eucalyptus, which compete for moisture and nutrient with other crops, the resulting yield near the tree lines will be comparatively low.
Eucalyptus is toxic, due to allelopathic properties which serve to reduce the germination of other plants.

Release of toxic chemicals from leaf, stem, and root extracts of Eucalyptus may inhibit the germination and seedling growth of crops.

Moreover, the leaf litter deposition from Eucalyptus vegetation and resultant soil acidity might also affect intercrop yield.

The oil of Nilgiri trees is highly flammable, further, a slight rise in temperature abates excessive vapourization, and a small amount of heat generated by the friction of sliding wood blazes the entire forest.

And the flame-fed heat accelerates the oil diffusion, hence creating a chain reaction.

This is the major cause of several forest fires across the world.

Incessant dousing wipes out the entire forest swiftly, thereby wiping out every possible lifeform in the environment, while the trunk of Eucalyptus is capable of germinating new scions.

The legal ban and the consequences

The Madras High Court on Jul 2022 directed the State government to ensure the removal of all invasive species of trees, including the eucalyptus tree, within ten years and banned further cultivation.

But most of the South Indian states have been cultivating the Nilgiri trees on a commercial scale since the early 1980s, and they have earnt a profit of 49 to 62.5 % at 8 years and several families in the western and eastern ghats mainly depend on Nilgiri oil extraction for livelihood.

Eucalyptus in the ayurvedic application

The natural detritus under the tree is resistant to microbial or fungal breakdown due to the oils. This makes the tree’s oil a wonderful antibacterial, antimicrobial, and anti-inflammatory.

Respiratory support:- For treatment of runny noses, coughs, asthma, and nasal congestion, eucalyptus oil also aids non-bacterial sinusitis.

Muscle relaxation:- The anti-inflammatory nature aids patients suffering from lumbago, rheumatism, sprained tendons, and sprained ligaments.

Antiseptic support:- A good medicine for treating burns, cuts, ulcers, sores, and abrasions also prevents infections.

Dental support:- The germicidal property of this oil makes it suitable in toothpaste and mouthwash to fight gingivitis, dental plaque, cavities, and mouth infections.

Pollution cleanser:- The tree can hold more carbon for each cubic inch of wood, and carbon gets absorbed quickly by its accelerated growth.

Eucalyptus and the timber industry

Nilgiris being a fast-growing variety completed 60% of growth in the first ten years, reaching heights up to 30 – 180 feet.

The total investment in the cultivation of this crop is around ₹2 lakhs per acre and the profit just from the timber material is around ₹8 – 10 lakhs (assuming 500 trees per acre).

Solution

The main purpose behind the ban is to prevent the specie from encroaching on the local environment and causing harm to essential crops. Therefore
- Rather than allowing the cultivation of these trees, the farmers can be licensed to harvest the existing trees in the available forest, and since the crop is proliferating the vegetation recovers quickly, or
- Separate islands can be raised to cultivate these crops where they will be isolated from the rest of the ecosystem. And India has several isolated islands in Lakshadweep and Andaman – Nicobar archipelago.
Except for timber, bonsai trees can be used for oil extraction.

The plant can be genetically modified to become non-invasive, as documented by a research team at Oregon State University led by Steve Strauss.
The CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) Cas9 gene-editing technique was used to modify a eucalyptus gene, which promotes flower formation.