Liana at IISc campus a botanist’s delight

By Rithu Dravid | NT

While the once ‘air conditioned’ Bengaluru has now become a heat trap with increasing high-rises - in the heart of the city thrives a miniforest on the Indian Institute of Science (IISc) campus.

Known for its beautiful gardens and majestic trees, the IISc, with its lush canopy of thick and dense trees is also a home to insects and birds.

The mini-forest that has transformed into a lush jungle of dense fruit and flowering trees, has had a positive impact on the microclimate of the IISc campus. A mini-forest in the IISc shows how a green lung space can thrive within the city.

Situated in the core area of Bengaluru, the ambience in the 400-acre Indian Institute of Science campus is in stark contrast to that of the city.

As you walk past the Centre for Ecological Sciences department (CES), and you stop short, you will surely spot the gigantic, woody weaves endlessly like a lace through a lush canopy. The hammock – like branches with twists the Entada Pursaetha DC scientifically called, is like a superstructure on the campus.

“They are supposed to be in the forest. It’s like a living dinosaur in the city. They spread their branches and leaves on top of every tree. Trees survive because they harvest sunlight and make food and survive. If when something covers there is no way these trees can make food eventually, they will dry up and die,” says Professor K. Sankara Rao.

The lovely liana, found only in the moist tropical forests of the Ghats can be spotted in a mini forest transformed into a lush jungle of dense fruit and flowering trees, this superstructure of the Entada has a mix of structures of a tree and a woody climber. Its erect trunk is made up of anti-clockwise-twisted pleats. The climber part comprises hammock-like, twisted woody stems. The structure has spread its canopy from one support tree to another that are long, leafless, cable- like stems (stolons) that navigated aerially.

A solitary genet that has attained a gigantic size in 25 years, the uncoiled trunk pleats have branched out into hammock-like, highly twisted, woody branches. Yet, no above ground part has twined around a support tree or its branches, hence Entada is not a twiner. Rather it’s a branch that mostly lies on the host branches for support and is occasionally entangled into them. A striking feature of Entada is the climbing branches shaped into an ‘Archimedes screw’.

“This is a wild plant, it starts with climbing like tendrils and it fuses to form hard stems. These stems curl and they creep onto the other trees. After becoming huge it cannot hold with the tendrils and therefore takes support of other trees,” says Rajakullayiswamy, a post-doctoral researcher.

The local names given to this unique tree are Gilla in Sanskrit, Palle Kai in Kannada, Kakavalli in Malayalam and Gila-Tiga in Telugu. The seeds of this tree constitute vivid turbid oil, saponin, glucoside and an alkaloid that have a medicinal value. The seed powder is mixed with coconut oil and used to relieve inflammatory and glandular swellings. Another beneficial property is that the seeds help in stimulating hair growth.

The IISc mini forest is a pristine green space, which is a home to many birds, animals and evergreen trees. This kind of green patch is not only an arboretum for evergreen tree species but also serves as home for several fauna and adaptable species.