Beautiful but destructive Lantana Camara Plants

Hyderabad: Lantana belongs to the verbena family of flowering plants which are native to the American tropics. Lantana’s flower clusters come in a wide range of attractive colours: red, orange, yellow, white and violet, beautiful to look at but bad for biodiversity.

History of Lantana

It was taken to Australia in the 1840s as an ornamental garden plant as its harmful effects on native plants were then still unknown. It was brought to India by the British for its beautiful flowers but studies now highlight its highly invasive, toxic and fast-spreading features, marking its place among the world’s ten worst invasive plant species, and viewed as species of high concern in India. It alters the nutrient cycle of the soil, competes for resources and space with the native species of plants and crops, besides reducing the forage plants for wild herbivores.

Invasive Species

Recent studies have found Lantana camara has already invaded more than 40 percent of India’s tiger range. The Shivalik hills, Central India, and Southern Western Ghats are the worst hit. With the ability to adapt to the changing climate, lantana can tolerate high temperature and moisture. The species now threatens about 300,000 square kilometers of Indian forests. Scientists highlight the urgent need of habitat-oriented management, biodiversity monitoring, and restoration-oriented studies to safeguard forests.

Problem in wildlife Sanctuaries

What was brought as an ornamental garden plant from Mexico, Lantana camera has now become a major problem to authorities of wildlife sanctuaries, forest department officials and farmers. It grows fast and does not allow other plants, shrubs and even grass to grow and as a result causes large scale migration of herbivores, leads to shortage of food sources for carnivorous animals like leopards and tigers. It has spread across the country from Mudumalai Tiger Reserve in Tamil Nadu to Jim Corbett National Park in Uttarakhand. Forest officials lament about its fast growth and huge budget needed to rid forests of lantana.

Can be made into handicrafts

Though lantana has its use as it provides livelihood to people who make handicrafts, its effect on wildlife and the eco-system is extremely detrimental.

Telangana

In Telangana, lantana infested areas are only increasing and the problem is acute in Pocharam wildlife sanctuary and Amrabad Tiger Reserve. Extermination measures in the last 200 years have failed and lantana has spread to more than 13 million hectares in India. The plant is toxic to birds and cattle as its leaves are poisonous, it increases water run-off and causes soil erosion. Experts say that with the decline of herbivores due to migration leads to shortage of food sources for leopards and tigers. In areas where lantana weed runs riot, grazing lands have shrunk. Its leaves are toxic to birds and cattle. Lantana grows fast and does not allow even shrubs and grass to grow. It increases water run-off and as a result soil erosion is common. The ripe berries of lantana contain toxic substances which affect cattle, sheep, horses, dogs, pigs and rabbits.

A menace

This plant has infested grazing lands, pastures, orchards and plantations like coffee, tea, cotton, coconut, oil palm, among others, while adversely compromising the economic viability of the crops. The lantana menace has led to increasing man-animal conflict, with about 50% of the state’s forest landscape being infested with this invasive flowering species. Wild herbivores, and therefore carnivores too, are moving towards human habitats as Lantana-affected crops, on which they would have otherwise feasted, no longer attract them.

Employment opportunities

However, there is a silver lining. The same Lantana Camara provides huge opportunities for employment for not just the tribal communities, but also many others who can exploit this fast-growing invasive flowering to make artefact and articles of daily use, including furniture.

Monetary assistance is being provided by several states to tribals on clearing Lantana and supporting artisans in making and popularizing Lantana products.

Years ago, the Bengaluru-based Institute of Wood Science and Technology (IWST), a research institute under the Indian Council of Forestry Research and Education of the Union Ministry of Environment and Forests, has already begun showing the way to exploit Lantana Camara, making doors, windows, foot mats and smaller articles of use from the residues of this plant compressed into a composite material.

Varieties of lantana

Multiple hybrid varieties of lantana were brought to India and over the 200 years of its introduction, the varieties have hybridized and formed a complex. The species is now able to climb up the canopy as a woody vine, entangle other plants by forming a dense thicket, and spread on the forest floor as a scrambling shrub.

Nurseries should stop stocking lantana

Nurseries are still selling this plant as it is easy to grow and attracts butterflies in urban gardens. Lantana has escaped gardens and has spread across the length and breadth of the country, invading roadsides, empty plots, agricultural fields, and forests.

Removing lantana

Eradicating lantana has been practiced in several protected areas in tropical India, where every year, thousands of acres of lantana invaded patches are either burnt, or are uprooted. Most of the time, the frontline forest staff works across the summer months in these forests manually uprooting this thorny plant one after the other.

A huge challenge

Protecting biodiversity and patrolling the forests against illegal activities becomes difficult with the presence of these invasive plants. Today, some forests like Bandipur Tiger Reserve are completely covered with lantana bushes, raising concern for both scientists and the forestry department.

Lantana camara invasion

Propagation is easy. Lantana is mainly dispersed by fruit-eating birds, monkeys, and ears but it also has a capability to grow from its root-stock, and nodes. A lot of fruit-eating birds, especially bulbuls are attracted to lantana berries. In every Tiger Reserve, a few hectares of land is cleared of lantana each year, but the area requires intensive surveillance. Since lantana seeds are already present in soil and they are also dispersed by many birds from surrounding areas, lantana regrows rapidly. To tackle this, a follow-up removal of lantana seedlings is necessary for a minimum of two years. It is a very big task and results are not encouraging.