BANFF, Alberta – Because of this importance of whitebark pine, Parks Canada is working across the mountain national parks of Banff, Yoho, Kootenay, Jasper, Revelstoke-Glacier and Waterton Lakes to try to give endangered whitebark pine a fighting chance. The higher elevation trees, which can live to be 1,000 years old, are dying off at an alarming rate. Climate change, more than a century of wildfire suppression and mountain pine beetle are all playing a role, but the biggest threat comes from white pine blister rust. …One clear sign of infection is orange blisters on the bark. McLellan said less than one per cent of whitebark pine are naturally resistant to the rust. …Charlie McLellan said last summer about 6,500 rust-resistant saplings were planted in the Banff National Park field unit and in Kootenay National Park – made up of whitebark pine and limber pine, another species recommended to be listed as endangered.