"Hair ice" - it is a type of ice that forms on dead wood. This phenomenon is observed between the 45th and 50th parallels of the northern hemisphere, as well as the 60th parallel.

in 1918 this phenomenon was described by the german Alfred Wegener (the author of the continental drift theory). In 2015 German and Swiss scientists proved that the culprit of this phenomenon is the fungus Exidiopsis effusa. Because it is the only one present in the wood in all cases of ice wool, and after treating the wood with fungicides it never appears again. It is true that how this wool survives and does not crystallize is still a mystery.