Quaking aspens in Gunnison National Forest, Colorado

© Tim Fitzharris/Minden Pictures

Quaking aspens in Gunnison National Forest, Colorado

This lovely photo highlights the white bark of the quaking aspens in Colorado’s Gunnison National Forest. Why are the aspens ‘quaking’? The descriptive name comes from the thin, nearly flat, flexible leafstalks, or petioles if you’re feeling scientific. When even a gentle breeze blows, the leaves of the quaking aspen move with vigor. From a distance, they give the impression that the whole tree is shaking.