As creeping saplings, they suck water and steal nutrients. They block the sun with their prickly needles. And their looming presence finally annihilates shrubby alpine competitors with spruce-like indifference.
OK, maybe this arboreal drama from the Kluane Ranges in southwestern Yukon Territory won’t make it as a matinee thriller. But a new innovative study by University of Alberta scientists found white spruce invading mountain tundra with surprising speed, pushing the tree line higher in elevation much faster than expected in response to climate change.
Once the summer warmth hit a certain level — the forest essentially pounced.


