Height: 5-20 meters
Needles: in clumps of 5
Lifespan: up to 1000 years
The whitebark pine produces some of the most nutritious seeds in the Canadian Rockies. Packed full of protein and fat, these pea-sized seeds are eaten by bears, squirrels and birds.
High up on a mountain slope a sturdy whitebark pine stands its ground against the elements. It grows in the harsh subalpine environment where few other plants can survive.
Whitebark pine has evolved over time to become an important tree of the high elevation forests along the Rocky and Columbia Mountain Ranges.
In these windswept places the whitebark pine stabilizes soil, creates habitat, and holds snow to control water flowing from the mountains in the spring. It is an impressive sight; however, it is now more common to see skeletons of these trees where they once thrived.
As hardy as the whitebark pine is, it is declining throughout its range, including within the mountain national parks. As a result, whitebark pine is now listed as endangered by the Species at Risk Act.
Whitebark pine faces 4 main threats.
This introduced fungus arrived in a shipment of white pine seedlings from Europe in 1906. Less than 1% of North American trees are rust-resistant.
Mountain pine beetle outbreaks in lodgepole pine forests are spreading to higher elevations due to climate warming. As a result, the beetles are also attacking whitebark pine.
Thicker bark helps whitebark pines survive low intensity fires which remove competing vegetation. Historic fire suppression reduced the opportunities for seedlings to grow.
Currently there is sufficient suitable habitat available to support the species. However, climate change may alter the distribution of suitable habitats across the landscape.
This species has a difficult time recovering from threats because it is slow growing and dependent on a single bird species to spread its seeds. The Clark’s nutcracker collects whitebark pine seeds to store for food over winter. Since the birds store more seeds than they need, many are left in the ground where they grow into new whitebark pine trees.
What are we doing
Over the past decade, we have assessed tens of thousands of whitebark pine trees to identify several hundred trees that appear to have a natural resistance to white pine blister rust. These rare trees are tested to prove rust-resistance, a process that takes 7 years in a controlled facility.
We climb whitebark pine trees that show natural resistance to blister rust and put a cage over their cones. These cages keep the cones away from animals that would break into them to eat their valuable seeds. When the seeds are ready in autumn, we collect them and send them to a nursery to be planted. After two years in the nursery, seedlings can be planted back in their mountain habitat.
Alpine collection by tentree
Fires in areas that don't pose risks to people or infrastructure may be allowed to burn with minimal to no intervention. This allows a more natural fire structure to return to the area.
Whitebark pines are often shaded out by subalpine fir and spruce. Prescribed fires in whitebark pine habitat create open spaces. The sun-loving whitebark pine thrives in these recent burn areas. During prescribed fires, existing stands of whitebark pine are protected.
Parks Canada has now developed a Terra Torch to burn small patches the way lightning strikes would have in the past. This technique has been used in Waterton Lakes National Park to burn small plots for planting whitebark pine seedlings.
Pheromones are chemicals that bark beetles use to communicate with each other. They let beetles know where they can find a mate and a place to lay eggs, or when a tree is “full” and they should try another tree.
Pheromone packets that mimic the natural pheromones of mountain pine beetles, called verbenone, are attached to whitebark pine trees to protect trees. The pheromones fool beetles into thinking that the tree is already full.
During the mountain pine beetle outbreak in Jasper National Park from 2013 to 2019, Parks Canada saved over 80% of rust-resistant whitebark pine trees from being killed by mountain pine beetle using verbenone.