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The title was the subject line in an email I received from Charles Butler, arborist and maintenance worker at Jean Lafitte National Historical Park & Preserve and Associate Certified Louisiana Master Naturalist.  His message contained the photos in this Nature Note.  I've never seen these beautiful, mysterious white items with my own eyes, but have known about them for years.

Since the white, icy objects look like curled ribbons, they are often called ice ribbons.  In fact, if you google "ice ribbons" and look at the images, you will see much variety and beauty in this natural phenomenon.  They may also be called ice flowers or frost flowers.

Ice ribbons appear after hard freezes under certain conditions.  My understanding is that the requirements are the presence of long-stemmed living plants (in this case our common fall flowering White Crownbeard, Verbesina virginica), unfrozen moist soils, and back-to-back freezing air temperatures.

In recent years, Greater New Orleans has experienced mild winters, with many species of plants remaining green throughout the winter.  This year was different, and on January 7th and 8th we suffered a "hard freeze" (temperatures plus windchill resulting in the low 20°s F - please, no giggling from our northern friends reading this - there is virtue to living in the subtropics!).

The first night the stems near the ground of the Crownbeard split vertically as the water and/or sap froze and expanded.  Temperatures rose above freezing during the next day allowing the water/sap to thaw, then dropped back into the 20s.  The resulting freeze caused the water/sap to expand and exude through the slits, thus forming thin sheets of ice resembling ribbons.  As long as the freezing conditions existed, the ice ribbons continued to grow.

Lucky Charles happened on the scene and was treated to a wonderland of ice in the park.  He found ice ribbon abundant throughout a large area of the Barataria Unit, especially around the Visitor Center and maintenance area.

People have written about this phenomenon for almost 200 years, and an excellent source of information is My World of Ice by Dr. James R. Carter, Professor Emeritus, Illinois State University, Normal.

Next time we have a hard freeze, make a trip down LA 45 to the Barataria Unit of the Jean Lafitte National Historical Park & Preserve.  You may share Charles' visual treat!

Ice ribbon on White Crownbeard (Verbesina virginica) stem near the Visitor Center of the Barataria Unit, Jean Lafitte National Historical Park & Preserve, January 8, 2014. Photo by Charles M. Butler

Another Photo by Charles M. Butler

Another Photo by Charles M. Butler

Another Photo by Charles M. Butler
Another Photo by Charles M. Butler A view of ice ribbon abundance and how they were distributed in the forest on January 8, 2014. Photo by Charles M. Butler