Gone are the days when bright red flowers drooping from treetops indicated the onset of summer in the city. Many such flowering trees, native to the city, also attracted several winged visitors, playing a crucial role in pollination. Today, much of the skyline is dotted with yellow shades of Copper Pod, Indian Laburnum and Siamese Senna.
The Indian Coral Tree and Flame of the Forest are fast disappearing from the cityscape, say botanists. “The garish red flowers of the Indian Coral Tree (Erythrina variegata), popularly known as Kalyana Murungai or Mulmurungai, attracted a lot of birds due to its copious nectar. Today, these trees are not only rare but also show severe gall infestation. Its flowers and leaves are marred by the unsightly galls,” says Pauline R. Deborah, assistant professor, Department of Plant Biology and Plant Biotechnology, Women's Christian College.
Flame of the Forest (Butea frondosa), commonly known as ‘Porasu' in Tamil, lent its name to Purasawalkam as it was found in abundance there, says Ms. Deborah. “Today, there is just one tree remaining in the area, and it is considered sacred. It is no longer found in parks or on roadsides and can be seen in few numbers inside protected campuses like Guindy National Park, Theosophical Society and Adyar Poonga,” she says.
G. Ramakrishnan, horticulturist, includes pagoda tree or Plumeria alba in the list of dwindling species. A hardy tree that produced white flowers, this species has come under attack from pests, he says. “Tamil Nadu Agricultural University has developed a parasite to counter the pest but its efficacy is yet to be seen,” he says.
The loss of native red blooms has heralded the arrival of exotic varieties such as Delonix regia (gulmohar, native to Madagascar), Spathodea campanulata (African Tulip Tree, native to Central Africa), Cordia sebestena (Red Sebesten, native to Caribbean) and there seem to be many takers for the latter.
“We should have a good mix of native and exotic plants. Shady trees are important to counter heat during the peak of summer,” says N. Kumar, Dean, Horticulture, Tamil Nadu Agricultural University.