Exidiopsis effusa (Hair Ice)

Hair ice consists of thin filaments of ice (0.02mm thick)
that are formed when the mycellium from the fungi Exidiopsis effusa emits moisture from wood

Silver Falls State Park
3/16/2021
Scroll Down for more Pictures

Hair ice, also known as ice wool or frost beard, is a type of ice that forms on dead wood and takes the shape of fine, silky hair. It is somewhat uncommon, and has been reported mostly at latitudes between 45 and 55 °N in broadleaf forests.

The meteorologist and discoverer of continental drift, Alfred Wegener, described hair ice on wet dead wood in 1918, assuming some specific fungi as the catalyst, a theory mostly confirmed by Gerhart Wagner and Christian Mätzler in 2005.In 2015, the fungus Exidiopsis effusa was identified as key to the formation of hair ice.

Hair ice, also known as ice wool, takes the shape of fine hairs - diameter near 0.02 mm, length up to 20 cm. It can be observed in forests, on dead wood, usually on the ground and sometimes on trees that are still standing.

Compare Hair Ice to the water that forms on Fomitopsis pinicola (Red-Belk Conks) by Guttation as compared to Traspiration.

Click here to see a Red Belt Conk emitting water by Guttation

References for more information:

click for reference #1; European Biologists Finally Solve Mystery of Hair Ice

Reference #2: Exidiopsiis Effusa - Fungi that help create hair ice