During the exceptionally warm springs of 2010 and 2012, plants bloomed earlier in the eastern U.S. than they have since the American writer and naturalist Henry David Thoreau started keeping records near Walden Pond in 1852.
Many plants now flower several weeks earlier than they did in the 19th century, a response linked to increasingly warmer springs due to global climate change.
Source: NBC News. Read full article. (link)