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Credit: Kenneth R. Dudzik, Northern Research Station, USDA Forest Service
The days are getting shorter, sleeves are getting longer, and autumn's display of fiery color is just getting underway in North America's cooler climes. And although the annual show is beautiful to behold, it also serves a very practical purpose. Trees are getting ready for the onslaught of winter, using a controlled, step-by-step process, according to Kevin T. Smith, a longtime plant physiologist with the USDA Forest Service in Durham, New Hampshire. "Trees are very smart," Smith said. "They don't really waste anything." To survive through the dark winter months, trees hoard their energy; lucky for us, the power-down process has some lovely side effects. Take a trip now to a few prime spots for leaf peeping some traditional, some surprising and learn about the biological strategizing behind the season's changes along the way.