Friday, October 8, 2010

Frost Flowers Coming Soon

Frost Flowers- click to enlarge
Last year I posted this article on frost flowers after they appeared.  This year I am giving you advanced warning.  Frost flowers (aka ice ribbons) occur on the morning after the first hard frost or two.  It pays to keep an eye on the forecast and get out early as the delicate frost flowers disappear soon after the sun hits them.
White Crownbeard
White Crownbeard, aka Frostweed, (Verbesina virginica) is the most common plant to produce frost flowers along Bull Creek, and we have had a bumper crop this year, growing to over 6 feet tall along the fence lines and road.  Verbesina species have distinctive winged stalks and large alternate leaves.  Most have yellow flowers except virginica whose petals are white.




Another common plant producing them is Yellow Ironweed, (Verbesina alternifolia) which can grow to higher than 9 feet tall.  It also has distinctive wings along its stalk, making it easy to identify.  For you botanists, there are other plants producing frost flowers include Dittany (Cunila origanoides), Hoary Frostweed (Helianthemum bickmellii), Helianthemum canadense, Pluchea odorata, P. foetida,  and P. camphorata.


Verbesina - winged stem


Frost flowers* are ribbons of ice which split the winged stems of these wildflowers as the sap freezes.  The spirals may extend more than eight inches up the stem or curl around the base in complex rosettes up to 8" in diameter.  The individual ribbons are so thin that you can see your fingerprint through them.  They sometimes recur as small basal collections after a third or fourth frost, so keep looking.         


There is more than you could ever remember about frost flowers at this comprehensive University of Texas site.
Pictures are from http://www.missouriplants.com/ which supplies excellent descriptions.
*  Other names include ice ribbons, ice flowers, ice fringes, ice fingers, ice filaments, ice leaves, frost ribbons, frost freaks, frost beards, frost castles (Forrest M. Mims III http://www.forrestmims.org/gallery.html), and crystallofolia.

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