In many places, spring happens gradually. But in far-north Fairbanks, Alaska, birch and aspen trees often put their leaves out over a span of just 24-48 hours, a dramatic event known as “greenup.”
In many places, spring happens gradually. But in far-north Fairbanks, Alaska, birch and aspen trees often put their leaves out over a span of just 24-48 hours, a dramatic event known as “greenup.”