If you go down to the woods today for a winter walk, you could be in for a big surprise.
People taking a stroll through the trees in counties Fermanagh and Tyrone have been encountering an unusual sight.
At first glance, it looks like candy floss has appeared on tree branches.
On closer inspection, you can see hundreds of individual strands of what looks like delicate white hair.
As soon as these are touched by human hand or winter sun, they melt away.
This strange phenomenon is called hair ice.