Because the state forest department's initiatives were mainly ineffectual, the government made a crucial policy decision to allow Tamil Nadu Newsprint and Papers Ltd (TNPL) to remove the invasive trees and use the wood to make paper. The drive, which began in January of this year, is the most extensive fight against invasive species to yet.
Supriya Sahu, Assistant Chief Secretary to the Government, Environment, Forests, and Climate Change Department, said that TNPL has expressed interest in removing two of the state's seven major invasive tree species, Wattles and Senna spectabilis, depending on economic feasibility. According to approximate official estimates, these two species have infested over 42,000 hectares.
"To begin, TNPL is cutting and removing Senna spectabilis trees in the tiger reserves of Mudumalai and Satyamangalam." Orders will be issued shortly to clear Wattle and Acacia as well. "We will probably be able to eradicate these two species in two years," Sahu predicted.
According to R Seenivasan, Chief General Manager (Plantation and R&D), up to 5,500 tonnes of Senna wood were recovered from 120 hectares. "It is believed that approximately 25,000 tonnes of Senna wood is present, of which we hope to extract 20,000 tonnes before the arrival of monsoon and the remainder by next summer," he said, conceding that Senna spectabilis is not the favoured wood for paper making.
"The wood is soft and has less cellulose content," Seenivasan explained. It also degrades within 7 to 10 days. We did this effort to assist the forest service. Wattle has a higher cellulose content in comparison." The official stated that TNPL's paper mills in Karur and Trichy use 10 lakh tonnes of wood from non-forestry sources, namely eucalyptus, acacia, and casuarina, and that senna wood will be blended with other wood for paper making.
The eradication effort is currently being conducted out in the Singara and Masanagudi areas, according to D Venkatesh, Field Director of Mudumalai Tiger Reserve. "We are using passive restoration or natural regeneration. We will closely monitor the region for a year to see how the ecology develops without any direct intervention. TNPL is not permitted to remove the trees and their roots. Trees will be cut close to the ground and debarked to guarantee that no new shoots emerge," he added.
According to the Tamil Nadu Policy on Invasive Foreign Plant Species and Ecological Restoration of Habitats, accurate published estimates of invasive alien species area in Tamil Nadu are currently unavailable. According to one estimate by an expert committee formed by the Madras high court's Madurai bench, the area under invasive alien species is 2,68,100 hectares. According to another estimate from the forest department, the impacted area is 3,18,041 hectares.
According to forest officials, the actual extent can be determined via remote sensing. "This can be used to estimate invasion areas and prioritise rehabilitation." According to a 2020 estimate, "exotic trees and agricultural growth have destroyed 262 square kilometres (69%) of montane grasslands in Palani Hills and 180 square kilometres (58%) of montane grasslands in Nilgiris."
