Lantana Camara is one such invasive species that since its introduction has become widespread from Southern India forests to Himalaya foothills.Lantana not only spreads fast but does not allow grass, shrubs or any other plant in its vicinity to grow leading to the migration or decline in the number of herbivores ultimately affecting the carnivores at the top of the food chain.
In a conversation with GnY, K V Sankaran, Former Director of Kerala Forest Research Institute said, “Lantana Camara has spread to over 60 countries. In India, it isn’t easy to control, especially in the forest areas. Eventually, the forest department will have to spend a lot of money in clearing it completely. Cutting Lantana is not going to help as it will re-sprout again. In fact it comes up very fast, compared to other plant species”
He added, “The entire root system needs to be removed. Otherwise, Lantana’s seeds will remain in the soil. It is an expensive process that will take a few years. Various biological control methods will not be able to eradicate Lantana”
In South America, insects and pathogens are controlling Lantana Camara’s population. It is looked upon as any other plant. But due to the absence of natural control agents in India, the plant spreads uncontrollably. It does not allow local seeds to germinate. Lantana seeds are spread by birds as well.
If one has to describe Lantana Camara, (popularly known as ‘balhari’ or ‘panchrangi’) in India, it is a thorny shrub upright, half climbing or sometimes hanging, reaching 2-3 m in height. The stems and branches are angular, bearing curved spines, arranged along the edges. Lantana flowers are small tubular structures that are yellow, pink or orange in colour while the fruits are fleshy varying in color from blue to black.
Diversity, broad geographic expansion and wide ecological tolerance are so inbuilt in any species of Lantana Camara, that the Invasive Species Specialist Group (ISSG) considers it as among 100 of the “World’s Worst” invaders (ISSG 2001). Therefore, the species has made itself imperative.
In India, Lantana Camara has been notorious for destroying entire local forest fauna, causing massive forest fires and blocking the natural reproductive cycle of forest trees.
There was immense forest cover loss in lower Shivalik hills, also known as Kandi area of Punjab due to invasion of lantana bush.Similarly, some of the worst hit national parks by Lantana Camara include Mudumalai Tiger Reserve, Nagarahole National Park and Bandipur National Park in neighbouring Karnataka and the Jim Corbett National Park in Uttarakhand.
The ‘Cut Root Stock’ methodology which is both cost-effective and has minimum impact on the soil was implemented in Himachal Pradesh with certain modifications according to suitable climatic conditions. Lantana was removed from many areas in the Solan forest division due to which local grasses and flora came up very well.
Despite threats posed by Lantana Camara to local plant species and wildlife, the plant continues to thrive. Lantana management and control is the need of the hour. A combination of biological control, mechanical and chemical methodology could be used. Until then, eradication of Lantana Camara remains a myth.