23 December 2010
Frost Flowers In Alabama
Posted by Dan Satterfield
A couple of viewers sent me some pictures of strange ice formations today. They are very beautiful (and rather rare) specimens of what are called “FROST FLOWERS”.
They form in areas where the ground is still warm but the air is quite cold. You usually see them after a sudden but intense cold snap. I’ve only seen them one time, but have been on the lookout for them ever since!
What’s likely happening is this: Water is rising from the warm ground into the stems of certain plants. It then flows out of cracks in the stems and suddenly freezes. The water may be supercooled, i.e. below freezing, but still a liquid. As it extrudes from the cracks in the stem, the water touches ice crystals on the stem, and ice immediately forms.
A good video on supercooled water from you tube shows how quickly water in this state can freeze. It just takes one crystal to start the process.
As water continues to rise in the plant (through capillary action) a ribbon of ice forms, and can curl into a flower like ice sculpture.
There are some incredible examples of this type of ice formation on a web page by Dr. James R. Carter at Illinois State Univ. He even wrote an article about them in WEATHERWISE magazine in 2009.
I suspect that frost flowers are more common in areas where the ground rarely freezes, but occasional cold snaps in winter can bring very cold temperatures. Some of the best examples I have seen are from Alabama and Tennessee. I kind of like the idea of making frost flowers the official Alabama state flower.
Unfortunately, it will be pretty hard to knock the Camellia out of that spot! Tennessee has the iris, and even I wouldn’t go that far 😉
Hi Dan. I believe the plant you have pictures of is the Harpers Umbrella or Harpers Buckwheat. I,ve seen it in the woods for the past 60 years. It is protected at Redstone because it is presumably so very rare and almost extinct. Nothing could be farther from the truth. In order to demonstrate that this plant is not endangered, I captured 90 pics in a space of 10 minutes and within a mile of my building at Tedstone. I think, on that particular frosty Morn in Mid December 2010, I saw at least 10,000 of these plants and at least a thousand on pics. They are not rare nor nearing extinction; they are elusive until they burst into glorious crystal flowers. The experts, not having spent as much time in the woods as I have, have completely missed the mark on this one. I have contacted various US Govt Agencies and state agencies to offer indisputable proof that, not only is this hardy plant alive and well, it can tolerate a lot of human traffic and thrive all the more. Notice in your pic, the stem or stalk burst as a result of the expanding, freezing sap. This marvelous event happens on the first deep frost of winter. Only then can you get an idea of its population. Its a Harpers Umbrella or Harpers Buckwheat. Ive got lots of pics, some of the Icey sap collected, some video of me gathering the so called ice flower but more importantly, lots of pics to demonstrate how plentiful they really are. Ron Bearden 256-955-9164
There are a few plants that form ice ribbons and one is Verbesina virginica. I noticed a few this past week on a walk in a nearby park; I was surprised since I almost always see them during the transition from fall to winter. If you would like to read more I’ve an older post http://www.clayandlimestone.com/2009/12/have-you-seen-frost-flowers.html.
Btw, love your blog and appreciate your reporting the science!
I am interested in documenting additional plants which produce frost flowers. I have been in contact with Dr. James Carter over the last year and both of us suspect there are more species than have been reported.
I have initiated a humble attempt to stimulate interest in the subject (see http://frostflowerstudy.blogspot.com/2012/10/do-you-grow-frost-flowers.html). I have posted lots of observations of Frost flowers on our Master Naturalist blog at Springfieldmn.blogspot.com.
If possible could you forward this on to Ron Bearden as well I would like to know more about his observations on Harpers Umbrella or Harpers Buckwheat.
To learn more about frost flowers, join the Frost Flowers Facebook Group: http://www.facebook.com/groups/frostflower/
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