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Atlantic Experiments

How Do Trees Know When It's Spring?

Apr 13, 2015 | 18 videos
Video by The Atlantic

It’s a warm, sunny day in April, and all the trees are in bloom. But how did they know it was warm and sunny? And on a warm, sunny day in February, what keeps them from blooming? Scott Aker, a horticulturalist at the U.S. National Arboretum, tells Robinson Meyer how the process works and what to look for.

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Authors: Nadine Ajaka, Robinson Meyer

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