Gold standard: Delhi’s streets awash in amaltas glory

New Delhi: Like the association of fairy pink cherry blossoms with Japanese cities or the blood red rhododendron with Himalayan hamlets, the luminous yellow of the amaltascould be Delhi's own claim to arboreal identity. As the temperature rises after the chilly winter, flowering trees like the palash, jacaranda, spathodea and semal struggle with the heat.The amaltas comes into its own then, being tolerant to heat and dryness. Clusters of yellow blossoms cascade from the branches, giving it the common name of ‘golden shower tree'.The amaltas (Cassia fistula) embellishes Delhi's canopy, roadsides and gardens with a spectacularly lively display. May and June are peak blooming season, and the urban landscape gets an annual visual respite. "They start blooming at this time and last for at least a month and a half, till the onset of monsoon, depending on shade or sun exposure," said horticulturist Ajay Kaushik, who manages the city's Garden of Five Senses.The yellow has the power to awe, but, Kaushik believes Delhi should also take to the pink amaltas."This variety blooms for a longer time, sometimes till the onset of winter with simultaneous fruiting," he said. While the yellow one's scientific name is Cassia fistula, those that bloom in shades of pink are Cassia javanica and its sub-species, Cassia nodosa. Kaushik said these were only growing at present in private gardens or farms in the city, but the Garden of Five Senses was planning to plant at least 10 trees.The species grows from the Indian subcontinent to Myanmar, but it has since also been introduced in other places, including China, Borneo, Egypt, Ecuador, Yemen, Australia, mainly for its showy blossoms.There is more to amaltas than just its pleasing yellow colour. Field biologist Faiyaz Khudsar, who is in charge of DDA's biodiversity parks, said it was a useful tree aside from being beautiful. "It has anti-bacterial, anti-fungal properties, can relieve burning sensation and constipation, and is also anti-ageing," said Khudsar. "Its leaves are broad, so the species helps in controlling particulate pollutants too."The tubular legume fruit, which looks like a small cane, has many medicinal properties, earning it another name, Sarvarogaprashamani, meaning one that cures diseases and shields the body. The legume which fruits after the flowering season ends is a weak laxative and is still preferred as a safer medication, especially for women from whom strong laxatives are not prescribed.The amaltas, however, is not easily propagated. There are only a few spots in the city such as the Central Ridge, where the species appears to multiply naturally, mainly due to the presence of wildlife like foxes, porcupines and civet cats there. For, the tree has a peculiar association with animals, particularly jackals. As naturalist Pradip Krishen, author of Trees of Delhi, explained, the amaltas depends on such wildlife for propagation."Botanist RS Troup, during his time at the Forest Research Institute in Dehradun in the 1920s, noticed that the amaltas' strong fruit did not burst on its own to allow the seeds to germinate. He carried out an experiment, leaving one set of legumes under a net cover and another set in the open," narrated Krishen. "Troup discovered that jackals and foxes liked the pulp of the fruit and cracked open the hard shell of the legumes. So while the protected fruits never germinated, those in the open were able to have the seeds freed from the casing by the animals, which also distributed the softs seeds when they defecated."Khudsar observed, "The slow spread or poor regeneration of the species in Delhi's forests show that the jackal population of the capital is shrinking." But as Krishen pointed out, "While the amaltas can look after itself in wild areas, in the city, human beings, because of the tree's sheer beauty, are still helping it propagate."