After the harvest moon, nature makes a final flourish before trees go bare. The dominant green of summer gives way to rusty reds, golden yellows, and autumnal oranges.
According to an Iroquois legend, three brothers are responsible for coating deciduous trees in color. Lured by a powerful dream, the brothers go hunting for a great bear in the sky. As the bear prepares for hibernation, the hunters pierce its hide with arrows. The celestial animal survives every year, but its wounds paint the trees red and gold.
Scientists say fall colors come from changes in leaf chemistry. With fewer hours of sunlight toward the end of the year, green chlorophyll fades revealing carotenoids and anthocyanins—plant chemicals responsible for fall’s warm color palate.
According to the U.S. Forest Service, specific colors are characteristic of particular species. Oaks turn red or brown; hickories, bronze; aspens, golden yellow; dogwoods, purple-red; beeches, light tan; and sourwoods—which starts to change by the end of summer—turn crimson.
Red maple becomes easy to identify once leaves turn, but other maples are less obvious. Sugar maple takes on a reddish-orange tinge. Black maple turns yellow.
Color intensity—especially with reds—depends upon the temperature, moisture, and sunlight levels throughout the year. A warm, wet spring and a sunny September/October are ideal conditions for a vibrant display.
For those hoping to enjoy the peak of fall color, the U.S. Forest Service normally offers regular updates on color changes in every region of the country. The federal fall color hotline is 800-354-4595. On Oct. 1, it had a message thanking callers and apologizing because “we will not have access to our mailboxes due to a lapse in federal funding. Please call back after funding is restored.”
The Forest Service website is still open: http://www.fs.fed.us/fallcolors/2013/.