'Shroom-Sicle

Day 122: Had it not been for a little ray of sunshine, I might have missed this. In fact, I did miss it on the first pass, although the fact that I chose to walk around the right side of the tree instead of the left when the trail gave me both options might have been responsible for the oversight. On my way back from Big Bridge, a fine needle of sunlight angled through the quilted overstory of hemlock and Douglas-fir to center like a searchlight's beam directly on this ice-encrusted specimen of Pseudohydnum gelatinosum (commonly known as Cat's-tongue). My camera battery was almost dead and I knew I had less than a minute to capture its frosty beauty before the fragment of sunlight disappeared, so I dropped to my knees in the mud even as I was changing settings. How I had managed to be in the forest with both camera batteries in terminal condition is another matter: a banana peel on the path of my attention to small details like recharging, and the unavoidability of Murphy's Law. In any event, I got half a dozen snaps before losing the light, and figured wet, dirty pantlegs were worth the sacrifice if even one of the shots turned out. As I stepped around the tree in the middle of the trail, I found another older, browner specimen also encased in ice, and a question rose in the back of my mind when I noticed that the shelf fungus adjacent to it was not icy, nor was the moss or any of the other vegetation in the area. What conditions prevailed that only Pseudohydnum gelatinosum turned into a popsicle? Why?