Quaking Aspens: Autumn Splendor: the Science Behind the Quaking Aspens' Golden Leaves

Quaking Aspen (Populous tremuloides) are the iconic slender, white-barked trees that paint our Western mountains yellow, gold, orange, and red colors in the fall. Aspens glow in a patchwork quilt of these different hues, showy against a background of dark green conifers, gray and black rocks, wispy clouds, and deep blue skies. Learn why the leaves turn red, orange and yellow in the autumn. This diary entry in Voices of the Valley Floor-a and Fauna unravels the mysteries of photoperiodism and how light affects the chlorophyll and xanthophyll in deciduous leaves.  Photo: Quaking Aspen (Populous tremuloides) on the road to Lone Cone near Norwood, CO. Photo Credit: R. Gaylord 2020.