Invasive Alien Plant Species in India

A recent Nature Sustainability study has highlighted that invasive alien plants are spreading across nearly 15,500 square kilometres of India’s natural areas every year. Over the last 60 years, these invasions have caused economic losses estimated at ₹8.3 lakh crore and pose serious threats to ecosystems, wildlife, agriculture, and rural livelihoods.

What are Invasive Alien Plant Species?

Invasive alien plant species are non-native plants that are introduced either intentionally or unintentionally into ecosystems outside their natural range. Once established, they outcompete native species, disrupt ecological balance, and cause economic, environmental, and human health impacts.

The spread of invasive plants is being accelerated by climate change, land-use changes, altered fire regimes, soil moisture variations, livestock grazing patterns, and widespread biodiversity loss.

Major Invasive Plant Species in India

Some of the most aggressive invasive plant species in India include:

• Lantana camara

• Chromolaena odorata

• Prosopis juliflora

Together, invasive plant species have already spread across 266,954 square kilometres of India’s natural habitats.

High-Risk Regions and Vulnerable Ecosystems

Regions facing particularly high invasion risks include:

• The Shivalik–Terai belt

• The Duar region of Northeast India

• The Aravalli range

• Dandakaranya forests

• The Nilgiris in the Western Ghats

Open ecosystems such as dry grasslands, savannas, shola grasslands, and the wet plains of the Ganga–Brahmaputra basin are especially vulnerable due to their ecological openness and frequent human use.

Impacts of Invasive Alien Plant Species

Biodiversity and Ecosystems

Invasive plants aggressively replace native vegetation, leading to ecosystem homogenisation, soil degradation, and large-scale ecological disruption. As native plants decline, herbivores lose their natural food sources, which in turn reduces prey availability for predators, destabilising entire food webs.

Livestock and Agriculture

The spread of invasive species reduces the availability of fodder and grazing lands, directly affecting livestock health and productivity. By 2022, about 2.79 million livestock and nearly 2 lakh square kilometres of smallholder farmland were exposed to invasive species impacts.

Human Livelihoods and Health

Invasive plants reduce access to fodder, fuelwood, and fertile land, undermining rural livelihoods. They also contribute to health problems such as respiratory ailments and deepen poverty by weakening income security. Around 144 million people have been exposed to risks associated with invasive plant spread.

Challenges in Managing Invasive Plant Species in India

1. Institutional Gaps
   India lacks a dedicated national mission or central authority to coordinate invasive species management.

2. Data and Monitoring Deficit
   There is no unified national database or long-term monitoring system for invasive plants.

3. Weak Biosecurity Measures
   Ineffective quarantine and border controls allow new invasive species to enter the country.

4. Limited Scientific Research
   There is insufficient research on species-specific control methods and long-term ecosystem recovery.

5. High Cost of Manual Removal
   Manual removal is labour-intensive, costly, and often ineffective without sustained follow-up.

6. Poor Post-removal Restoration
   Many cleared areas are not restored, enabling rapid reinvasion by invasive species.

Measures Required for Effective Management

• Establish a National Invasive Species Mission with clear leadership and mandates, and integrate invasive control into climate adaptation, watershed management, and ecosystem restoration programmes.

• Develop a centralised GIS-based database, early-warning systems, and a nationwide monitoring network.

• Strengthen quarantine screening, border biosecurity, and import regulations for plants, seeds, and soil.

• Increase research funding for ecological modelling, biological control, and restoration science.

• Promote community-led removal efforts, supported by mechanical tools and sustainable utilisation options such as biofuel production.

• Ensure active ecological restoration using native grasses and shrubs after removal to prevent reinvasion.

Conclusion

The rapid expansion of invasive alien plant species in India poses a serious threat to biodiversity, ecosystems, and rural livelihoods. Addressing this challenge requires urgent, coordinated national action, strong institutions, scientific research, and community participation. A comprehensive national mission is essential to build long-term ecological resilience and safeguard India’s natural heritage.