In the capital of the Indian state of West Bengal, tourists flock to see what at first glance looks like an expansive forest. Branches of green leaves create an expansive canopy over the Acharya Jagadish Chandra Bose Botanical Garden — about the size of a Manhattan city block. But the most interesting thing about this collection of plant life is that it's not a collection at all; it's one massive tree, known simply as the Great Banyan Tree, and all those apparently distinct members of a forest are actually one of 3,600 aerial roots.
If you're wondering how in the world one tree could cover about 14,500 square feet (1,347 square meters) of space, grow branches as high as 80 feet (24 meters), and survive over two and a half centuries, it's time to get to know a special species known as the banyan.
Alvarez and Schutzman say the banyan's history is rooted (pun intended) in South Asia. "Only one species from India — Ficus benghalensis — was the original banyan, named after the Hindu traders or merchants that conducted business under the shade of the species," the duo write via email. "Now, the term is used generically for several species of Ficus that have a similar life cycle and belong to one group of fig species (Urostigma)."Alvarez and Schutzman say the banyan's history is rooted (pun intended) in South Asia. "Only one species from India — Ficus benghalensis — was the original banyan, named after the Hindu traders or merchants that conducted business under the shade of the species," the duo write via email. "Now, the term is used generically for several species of Ficus that have a similar life cycle and belong to one group of fig species (Urostigma)."
How Do They Grow?
These days, when people refer to a "banyan" they could be referring to any one of the 750 species of fig tree that are pollinated only by a specific species of tiny wasps that breed inside the fruit of their old trees. All banyans fall under the super cute and not-at-all-threatening-sounding category of "strangler figs." This means the trees grow from seeds that land on other trees, sending their own roots down to smother their hosts and then growing into smaller, branch-supporting pillars that look like new tree trunks.
"These plants all start life as a seed that germinates on another tree, grows as a vine dependent on the tree for support, and eventually strangles its host tree, subsuming its structure," Alvarez and Schutzman write. "Later, roots grow from outward-extending branches and reach the ground, becoming trunk-like and expanding the footprint of the tree, sometimes gaining it the colloquial name of a 'walking tree.'"
And while Kolkata's Great Banyan is by far the greatest of them all, banyans as a species dominate, size-wise — at least in broadness: they're the world's biggest trees in terms of the area they cover. When it comes to overall volume, however, they lose to the giant sequoia, a species led by a 2,000-year-old tree named General Sherman living in California's Sequoia National Park that's about 52,500 cubic feet (1,487 cubic meters) in volume.
Cultural and Historical Significance
The banyan is considered sacred, a particularly meaningful tree in India and other parts of the world, with rich historical and spiritual ties. Referred to as "the Vata-vriksha," in India, the exotic Indian banyan is associated with the god of death, Yama, and is often planted near crematoriums outside of villages.
In Hinduism, it's said that the deity Krishna stood beneath a banyan tree at Jyotisar when he delivered the sermon of the sacred Sanskrit scripture, the Bhagavad Gita. And Hindu texts written over 2,500 years ago describe a cosmic 'world tree,' that references an upside-down-growing banyan that has roots in heaven and extends new growth from trunks and branches down toward Earth to deliver blessings.
According to historians, Alexander the Great and his army were the first Europeans to encounter the Indian banyan when they arrived India in 326 B.C.E. But it was when the British invaded India that the tree took on a newly dark purpose, often used as gallows to execute rebels who resisted their rule. By the 1850s, hundreds of men were hung from the branches of banyans. When India gained independence, the people reclaimed the banyan as well, making it the national tree.
The Banyan of Today
Where Can You Find Them?
Banyans are native to and thrive in India and Pakistan but these days, variations of the majestic trees can be found in tropical regions such as areas of Florida. "These Ficus species can only grow in the tropical and subtropical areas of the world because they are not sufficiently cold-hardy to live outdoors in colder climates," Alvarez and Schutzman write. "In some places such as south Florida, the False Banyan, Ficus altissima, has become invasive."
There's also one famous species representative on the Hawaiian island of Maui: the Lahaina Banyan Tree, planted in 1873 and presented to the sheriff and town by missionaries from India. Now 40 feet (12 meters) tall, the Lahaina Banyan has a canopy circumference spanning a quarter-mile (0.4 kilometers).
Today's banyans aren't just beautiful and symbolic — this species also come in handy for modern purposes. "This ability of tiny Ficus roots to become trunk-like structures is used by the people of Meghalaya, India, to create foot bridges across streams that become raging rivers during the monsoon season," Alvarez and Schutzman write. "They weave the tiny roots of our well-known rubber tree (Ficus elastica) together to cross the streams. They enlarge and form sturdy structures that can live 500 years or more and do not get washed away during the storms."
How to Care for Banyan Trees
And while you may be tempted to grow your very own great banyan tree now that you know the unique magic of their aerial roots (literal and figurative), you may have to settle for a painting or photo print homage.
"The best way to care for them is to give them plenty of space and warm, wet, humid weather — so most banyans don't make very good plants for regular home gardens," Alvarez and Schutzman write. "A few species have adapted to indoor environments and can be grown in bright indirect light with regular watering, however they are not as long-lived as their relatives in the wild."
Now That's Interesting
After Alexander the Great and his army came across the banyan in 326 B.C.E., they reported their findings back to Greece's Theophrastus, aka the founder of modern botany. This info is reportedly what led 17th-century English poet John Milton to write that Adam and Eve made their first clothes out of banyan leaves in the book "Paradise Lost."
Banyan Tree FAQ
Where are banyan trees found?
Banyan trees are plentiful in India and Pakistan, where they’re the national tree. However, some can also be found in other tropical regions, such as Florida.
How is a banyan tree beneficial?
Studies show that medicines derived from Banyan trees are highly effective in aiding in digestive distress and infections of the gastrointestinal tract. The tree’s antibacterial properties are known to help many digestive disorders.
How do you identify a banyan tree?
Banyan trees have long aerial roots found that grow down from the branches into the ground where they absorb water. The branches are unusually long, growing into a canopy of new leaves and can spread great distances.
Can I grow a banyan tree?
You should only attempt to grow a banyan tree if you have a yard with a lot of space and the right climate. The growth of this tree can be quite large, so they shouldn’t be planted anywhere near a house, driveway or streets.
Where is the largest banyan tree?
The largest and widest banyan tree stands tall in India near Kolkata. Growing for over 250 years, this tree covers 3.5 acres of land, which is approximately 14,500 square meters.
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