Kolkata breaths easy as cyclone Dana clears allergy-inducing Chhatim flowers
Times of India | 31 October 2024
Cyclone Dana brought heavy rains to Kolkata, relieving allergy and asthma sufferers by causing Chhatim trees to shed their fragrant flowers. While the trees' high air pollution tolerance makes them valuable, their scent led to planting restrictions. KOLKATA: Cyclone Dana triggered heavy rains, but the city was spared any significant damage. However, it did bring relief to those with allergies and asthma, as the heavy showers led to "Chhatim" trees (Alstonia Scholaris) shedding the flowers that have a strong fragrance.
The off-white flowers occur in clusters and give off a fragrance during the Bengali season of 'Hemanta' (Oct-Nov), which usually marks the advent of winter.
Chhatim bloom brings both beauty and breathing troubles
While many enjoy the blooming season, residents with breathing trouble residing along Bagbazar Street, Ballygunge Circular Road, Southern Avenue, J L Nehru Road, and Central Avenue, where many decades-old Chhatim trees still exist, experienced trouble sleeping since mid-October due to the profuse flowering of the trees.
With the trees shedding the flowers during the rain, they are again able to breathe easily and keep the windows open at night.
"I particularly love night walks along the quiet stretch of Ballygunge Circular Road after 8 pm, particularly during this time of the season when Chhatim flowers are in full bloom and spread a sweet aroma across the street," said Ashoke Malhotra, a businessman residing at Ritchie Road.
"The evergreen single-stem trees with densely covered shades by leaves give a canopy-type effect, a perfect choice for an avenue tree in Indian metropolitans. The tree also has high preference due to its high air pollution tolerance index (APTI)," said Santanu Saha, HoD, post-graduate department of Botany in Bidhannagar College. In Sanskrit, the tree is known as "Saptaparna," meaning "seven-leaved," as the tree is made by a bunch of leaves, usually seven, arranged in a whorl. "The full bloom season attracts large numbers of insects, particularly moths, for pollination, apart from butterflies, bees, and wasps," added Saha.
The state tree of West Bengal was once a very popular avenue tree due to its sturdy nature and resistance to strong winds, as well as its ability to mitigate vehicular emissions. But fresh plantation of Chhatim in the city by KMC Parks and Squares department was discontinued following health concerns.
Changing preferences in avenue trees due to health concerns
"In the last five years, we did not plant Chhatim trees due to the strong scent of its flowers that caused breathing problems and sleeping difficulty for the city’s sensitive urban populations," said Sarbani Roy, botanist from KMC’s Parks & Square department.
"I usually keep all my windows closed during the full bloom season at night as the strong odour creates breathing issues for me," said Mandira Mullick, who resides at Lake Road.
"Due to the limitation, our preferable avenue trees in Kolkata are now being shifted to Amaltas (Sonajhuri), Tabebuia (pink Trumpet), Spathodea (Rudra Palash), apart from existing Mahogany, Neem, Debdaru, Bakul, Jarul, and Mahua," added Roy.
A study found that during the dry season, huge loads of comose seeds and heavy loads of bio-particulate material produced by the decomposition of empty follicles travel through the air and cause allergy problems in sensitive people.