This is just awesomeness! Hair ice, also called silk frost, is a type of ice formation that looks like silk and seems to only appear on woody, barkless materials on the ground. The ice structures tend to grow out of the pores in the wood, sort of like hairs on the human head. It grows outward from the surface of the wood as super-cooled water emerges from it, freezes and adds to the hairs from the base. These amazing ice structures have been found in places like Germany, Canada, Switzerland and the Pacific Northwest in the United States.
Dr. James Carter is a professor in the Department of Geography-Geology at the University of Illinois has collected photos and other reports (dating back to 1884) of hair ice. He concludes that the fibrous ice crystals seem to be caused by the pore structure of certain woods, and only forms where the bark has been removed. Reportedly, the phenomenon is reproducible: if you find a piece of wood growing hair ice, you can warm it up, then re-freeze it, and it will grow hair ice again. These formations are likely attributable to diurnal temperature variation -- the difference between temperature variations from day to night.
Unconfirmed reports on the Internet state this also happens to dog poo in the Pacific Northwest. That’s kinda awesome too.