Each fall, after the first hard freeze, frost flowers burst into bloom. These ephemeral ice blossoms last only until sunrise when they melt away again, but Alan Templeton, the Charles Rebstock Professor of Biology Emeritus in Arts & Sciences, has made a hobby of waking early to photograph each year's crop. These "flowers" are formed when the water in plant stems freezes and expands, cracking the stems open and allowing the moisture to continue grow and freeze into long, curling ribbons.
This little-known process, technically called ice segregation, was the subject of an article in the September-October 2013 issue of American Scientist. Video produced and edited by Sean Garcia, Arts & Sciences Communications, for Arts & Sciences' 2013 video holiday greeting. Music by Sean Garcia. Many thanks to Alan Templeton and Diana Lutz.