PESHAWAR, April 7: A task force set up to recommend measures for the protection of Shisham tree against its common disease Die-back, has so far been unable to find the exact causes of the viral infection, which is posing a potential threat to this tree grown in natural and artificial forest ranges of the country.

Scientists believe that certain stresses including aridity, salinity, water-logging, soil compaction, hazardous materials, heavy lopping could be some of the main factors that cause the disease, apart from some other ecological reasons.

“Perhaps this is a syndrome, not a disease,” maintained Dr Mohammad Iqbal Sial, a member of the National Task Force (NTF) on Shisham tree disease, saying that the disease had largely affected Shisham forests in Pakistan and other forest ranges in the South Asian countries. In Nepal and Sri Lanka, Shisham forests on vast areas have been affected by the disease, the official said.

Director of Forest Management Centre, NWFP, Abdullah Khan Khattak said: “Die-back is a very complex problem and have numerous reasons. Old age can be one of them.”

A retired entomologist of Faisalabad Agricultural University recently suggested the stereotype formula of disinfecting the plant, but most of the scientists in Peshawar say this is not practicable.

The federal government has constituted a six-member task force to investigate the exact cause, the extent of the damages to Shisham trees and to recommend preventive and control measures for the disease.  

The Punjab Forest Department has reportedly approved PC-1, costing Rs20 million to start research work on the die-back disease in the province.