While the State government taking serious efforts to eradicate invasive species that have spread across forests, some of the world’s most invasive species are spreading fast around Valankulam and Periyakulam (Ukkadam big tank) in Coimbatore city which were beautified under the Smart Cities Mission . The invasive plants, at least three of which were identified by The Hindu and confirmed by botanists, were planted for ornamental purposes. The exotic plants have now flourished fast posing threat to the native ecosystem of the tanks which used to attract residents and migratory birds before the beautification works. Two of the invasive plants used for ornamental purpose Lantana camara and Sphagneticola trilobata used for the beautification works are among the ‘100 of the World’s Worst Invasive Alien Species’, a list published by the Invasive Species Specialist Group, a specialist group of the Species Survival Commission of the World Conservation Union (IUCN). The third plant, Parkinsonia aculeata aka Jerusalem thorn, is native to tropical America and is considered as an invasive species in many countries including Australia. While Lantana camara has spread in almost all forest areas, Sphagneticola trilobata was also getting introduced to the wild. Once spread, Sphagneticola trilobata forms thich bed on the ground and does not allow other plants to grow, experts said. S. Bharathidasan, member of State Board for Wildlife and secretary of the non-governmental organisation ‘Arulagam’, said that the use of exotic species for beautification works was inappropriate as the State government itself was taking efforts to eliminate such invasive plants from the forests. “There are equally beautiful native plants which can be used. Worldwide, the need to promote native plants is gaining momentum due to the impacts of exotic species,” he said. According to B. Subbaiyan, a botanist, Sphagneticola trilobata which locals used for ornamental purposes has now started spreading fast forests in Valparai and in the Nilgiris. “There are around 150 species of common native plants that could be used for ornamental purposes. They do not require much care and can be maintained easily. Aromatic plants can also be used in places like parks,” he said. Coimbatore-based nature enthusiast K. Mohanraj said that the inclusion of exotic plants in the beautification works shows that they were carried out without proper study of the environment. “The invasive plants should be removed immediately before they propagate and spread further. They should be replaced with native plants. A butterfly garden could also be created with native plants,” he said.
