The Nodal Centre for Biological Invasions (NCBI) at the Kerala Forest Research Institute (KFRI) has come out with a management plan to eradicate Senna spectabilis, the exotic invasive plant that is posing a severe threat to the State’s wildlife habitat.

Based on the results of the experimental study done at the Periyar Tiger Reserve, the plan envisages landscape-level management of the tree. The two key factors considered in developing the management protocol were the fast nature of the spread of the tree in natural forests, and restoration of natural forests based on landscape.

The results of the field trials were presented at a recent national conference on bio-invasions organised by the Kerala State Biodiversity Board. The management plan stipulates that there should not be an attempt to kill the trees before a detailed reforestation programme, said T.V. Sajeev, Chief Scientist, KFRI. The invasive species has to be removed using a threefold approach for large trees, large saplings, and small saplings, he said.

The large trees need to be debarked from breast height downwards (1.3 m above ground level), including the collar part of the tree.

Once the trees start to dry up, their soil seed bank will become active and a large number of plantlets will sprout. The larger saplings can be uprooted using specially designed weed pullers.

The third is the removal of small plantlets which need to be removed mechanically.