Half a decade on, he says the typical trees of the Sundarbans are on the brink of extinction, with top-dying disease -- where the uppermost parts are damaged first with loss of leaves -- affecting the palm species due to salinity.

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"The fertility of Golpata has been reduced and the palm trees are in a dying state due to poor collection and trimming. If the trees remain untouched for long, their fertility reduces significantly," says Bachchu, the president of the Sundarbans Foresters Traders Federation.

Golpata leaves are widely used by the people of Khulna for building thatched roof houses. The leaves of the trees grow straight up from the ground. Overall, it is an important product of the mangrove forest due to its demand among local people.

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Experts fear that if the locals refrain from collecting the leaves, then the growth of the trees could be affected. To increase the proliferation of the trees, they need to be trimmed regularly.

The experts say that hundreds of thousands of leaves of Golpata in the Sunderbans are dying as the trees have been failing to get nutrients from the roots. In some trees, all the leaves of some trees suffer damage, except the middle-baby ones.

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Forest officials and bawalis (wood collectors) say the leaves of the important trees of the Sundarbans suffer damage due to low collection that affects their fertility.

According to Bachchu, “There were three wells in the Sundarbans under the Khulna west zone division and Golpata leaves were collected from the same. Now only one well is available for collecting the leaves, while the remaining lay unused.”

Besides, the use of the leaves is (not are) also declining among the people of the coastal areas as they now depend on corrugated iron sheets for roofing, he says.

However, sources at the Sundarbans west zone office say there are only two wells under the zone and Golpata leaves are collected from the same.

In the past, people used to collect Golpata leaves from Aar-Shibsha, Shibsha and Bhadra and Satkhira well under Satkhira range. In 2017, the wells except one were designated as sanctuary, thus prohibiting collection of all types of wild resources.

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Earlier, nearly 1,000 bawalis used to collect the palm leaves from the Sundarbans, but now only 250 are available.

Prof Nazrul Islam of Khulna University, says, “The disease is common and all that's needed is trimming. The bawalis, who have permits to collect Golpata leaves, have been repeatedly asked to clean the trees after collecting their leaves. However, most of them refrain from doing so."

"Moreover, in some cases the bawalis damage the middle-baby plant during collection. The forest department should provide training to them," he adds.

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When contacted, Abu Naser Mohsin Hossain, the divisional forest officer, said, “It is right that proper trimming helps the trees to grow but the demand for Golpata leaves has been declining. Earlier, the demand for the leaves was 10 lakh tonnes a year, but now it has come down to 2 lakh tonnes."