BOB HIRSHON (host):
The future of fall foliage. I’m Bob Hirshon and this is Science Update.
Climate change may lead to duller fall colors. This according to Appalachian State University plant ecophysiologist Howard Neufeld. He says many trees use sugars to make rich red pigments. They start storing those sugars when nighttime temperatures drop in late summer.
HOWARD NEUFELD (Appalachian State University):
If it’s warm, the trees are more active metabolically, so they burn up those sugars in respiration, and there’s less left to induce the formation of the red pigment.
Warmer temperatures also delay the color change, so there’s more time to burn up or transport sugars out of the leaf. What’s more, climate change is forcing some of the brightest trees, like sugar maples, further north, with potentially less spectacular species taking their place. Neufeld says the potential effects of climate change are highly complex, but there’s good reason to expect that fall foliage won’t be quite the same in the future. I’m Bob Hirshon for AAAS, the Science Society.