As the weather cools and the days get shorter, leaves’ green chlorophyll disintegrates. Other colors within the leaves become visible. These orange and yellow pigments are always there, but in summer, the chlorophyll masks them. In autumn, the leaves bare all.
Maine's chlorophyll breakdown (courtesy of Bethel Area Chamber of Commerce)
Leaves first show their true colors at high elevations and in the north. The blaze cascades southward and down mountainsides as the season progresses. Leaf peepers, grab your trekking poles and daypack, and check out these trails in the U.S. East, West, and Rocky Mountains.
