From UPSC perspective, the following things are important :
Prelims level : Senna spectabilis
Mains level : Impacts of the invasive alien species
The Kerala Forest Department is planning to adopt steps to arrest the rampant growth of invasive plants, especially Senna spectabilis, in the forest areas of the Nilgiri Biosphere Reserve (NBR).
- The Senna spectabilis species was planted as avenue trees in Wayanad. The vayal ecosystem (marshy land) of the forest area now has this plant in large numbers.
- The spread is posing a major threat to the forest areas of the reserve, owing to its quick growth and coppicing character.
- The tree species was found in nearly 10 sq km area of the 344.44 sq km sanctuary around five years ago.
- The plant has started to invade the adjacent Bandipur and Nagarhole tiger reserves in Karnataka and the Mudumalai tiger reserve in Tamil Nadu.
- Now, it had invaded to more than 50 sq km of the sanctuary Wayanad WLS.
- A recent study of the Ferns Nature Conservation Society recorded the presence of the plant in 78.91 sq km area of the sanctuary.
- An adult tree grows up to 15 to 20 metres in a short period of time and every year distributes thousands of seeds after gregarious flowering.
- The thick foliage arrests the growth of other indigenous tree and grass species and causes food shortage for the wildlife population, especially herbivores.
- Moreover, wildlife will not feed on the leaf of the treeas it is not palatable for them.
- The allelochemicals produced by this plant adversely affect the germination and growth of the native species.