Darjeeling, March 26: In a major policy shift, forest officials have decided to replace the monoculture pine (cryptomeria japonica) forests with other indigenous trees to help restore the bio-diversity of the hills.

The issue was broadly discussed during the recent meeting of forest officials at Sukna, near Siliguri, where they largely agreed to include more plantations of local trees in its working plan for the region.

Some of the local trees that the authorities could plant in the future include Buc (Quarcus limellosa) and Qatus (Quarcus pachyphilla).

A.K Jha, the divisional forest officer (working plan division, (north), told reporters today that of the estimated 6,000 hectares of forest cover in the hills, an estimated 33 per cent came under monoculture plantations.

“Pines cannot be removed at once as it is known as the poor man’s timber and its sale in the local market is also considerably high. But it has been found that its disadvantages far outweigh the advantages,” said Jha.

The officials added that the success of the joint forest management (JFM) programme in the hills had also prompted the officials to go in for a change in policy.

“Earlier pine saplings were planted as no cattle would graze on them but with the implementation of the JFM programme, the villagers are themselves helping in conserving the forest cover. As a result, cattle grazing is no longer a problem,” said Jha. He added that so far 126 JFM schemes had come up in the hills after the programme was started across the country in 1989.

Umesh Diwvedi, secretary of the Environment Protection Society, who has conducted extensive studies on pines, said: “The pine trees do not allow any undergrowth to come up, expect banmara (eupatorium), and this is definitely destroying the bio-diversity. Moreover, during our research we have found out that no earthworms are found beneath the pine covers but the same can be seen beneath an indigenous plant growth in the same area.”

Dwivedi attributed this to high organic acid content in the leaves of the plant and also due to the slow decaying period of pine leaves.

The Environment Protection Society, along with the forest department, had also replaced monoculture pine forests with indigenous tress at the catchment area of jhoras (streams) at Rishihat in 1993. Following this, the jhoras were found to have been revived. “As a result of pine tree cultivation and loss of bio-diversity, the soil cannot retain moisture but if mixed planting is done, this problem does not exist,” Jha said.

Pines, which grow at an altitude between 3,000 ft and 7,500 ft, were first introduced in India in 1865 by the British and were initially used for making tea chests and later for timber purposes.

However, forest authorities maintained that though pine timber is in demand, the timber output of pine trees was relatively less than that of indigenous trees.