<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/ice-hair-1.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/ice-hair-1.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/ice-hair-1.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > 1 of 3 Hair Ice Rare hair ice was discovered this month in Loch Lomond and The Trossachs National Park. (Suzanne Humphris)

Park rangers in Scotland recently spotted an eye-popping, hair-like ice formation growing on dead trees, a phenomenon that scientists have only just begun to fully understand.

"I was walking through the woods, and there were loads of this stuff!" exclaimed Suzanne Humphris, ranger team leader for Loch Lomond and the Trossachs National Park, in a phone interview with weather.com. "Close-up, it looks just like my cat's underhair!"

This bizarre, cotton candy-like form of frost, known as hair ice, is highly unusual, found only in a narrow geographic band of the Northern Hemisphere. The fuzzy icicles take shape from fungi inside the roots of rotting wood when humidity levels are high and temperatures are cold. The water gets pushed out slowly, forming the fluffy ice silk. When touched by a human hand, the hair ice quickly dissolves.

(MORE: Incredible Ice Hair Forms from Fungus )

Although hair ice was first discovered in 1918, its presence has baffled researchers for many years. Last July, scientists in Germany and Switzerland discovered fungal activity was largely responsible for the ice formation, hypothesizing that the hair ice was created by a fungi-related recrystallisation inhibitor, they reported in Biogeosciences , a journal published by the European Geosciences Union.

"The fungi species that acts as a catalyst for the phenomenon is Exidiopsis effusa," Humphris said.

She noted that with Scotland's rainy and unseasonably mild weather conditions , it's been easier to locate hair ice.

"If there was other snow and frost, you wouldn't notice it," she observed. "Nature is awesome, you never know what you're going to find."

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