Autumnal equinox
This thicket of aspen trees is on the Last Dollar Road, an 18-mile scenic drive in southwest Colorado that is as dramatic as its name suggests, with switchbacks and stunning views of peaks and meadows and of course the aspen trees that paint the land come September. Aspens thrive in the cold winters and cool summers of Colorado, where they grow at altitudes between 5,000 to 11,000 feet, typically reaching heights of 50 feet. Their distinct, round leaves quake in the wind making it appear as if the trees are glittering in the sunlight. Aspens generally grow on west-facing slopes, gorging on the afternoon sun. They're among the world's largest living organisms because aspen groves share a single root system. They're also the state's only native deciduous tree and cover about a fifth of its forested land.