Snow hair is a wonderful natural phenomenon that you can encounter in deciduous or mixed forests. From a distance it just looks like a snowy remnant. But when you bend down close to the wood, you suddenly see tiny silvery fibers. They can be up to 20 cm long and 0.01 mm in diameter, which is about the same thickness as a human hair. This is why Ice’s hair is sometimes called “King Winter’s beard.”
It’s the pink-and-blue waxy scurf fungus (exidiopsis effusa) that sculpts these thin strands of ice from ice crystals. Scientists believe she creates her little artworks using lignin and tannin. These are the particles that are released during the decomposition of wood. When the lignin and tannin mix with the water pushed out of the wood’s pores, they prevent the formation of large ice crystals, which results in ice hair.
Of course, the weather plays an important role in this whole process. First of all, deciduous wood (usually oak or beech) must be sufficiently moist. But snow or rain alone won’t get you there. There must also be enough water vapor in the air. Otherwise, the moisture escaping from the wood will evaporate rather than solidify. For the latter, you also need a temperature below freezing. On average, this happens about 46 times a year in Belgium. Finally, it must also be windless and there must be sufficient shade. A little sun and… poof… ice hair gone.
