Hair Ice

The very unusual Hair Ice is formed when the air temperature is just below freezing but the ground remains just above. This phenomenon only occurs because of the the presence of the fungi Exidiopsis effusa which is normally invisible and grows inside fallen wood. All living, metabolising fungi produce carbon dioxide, this acts to push water out of wood which would then normally just freeze as a simple crust of ice, but the Exidiopsis effusa causes this water to freeze into thin hair-like strands. In order to achieve this it is thought that this fungi produces some kind of "re-crystallisation inhibitor" which acts to stabilise and prolong the delicate hair-ice structure, thereby stopping it collapsing into a simple ice crust - quite remarkable!