The temperature dropped to minus five last night (minus twenty for disciples of Anders Celsius), the coldest that I’ve seen in Sewanee. I took a walk in Shakerag Hollow this morning to see how the woods were faring in this unusual chill. I’ve never experienced such silence here. The quiet was punctuated by woodpeckers drilling meager breakfasts from high in the canopy and trees occasionally snapping out gunshot sounds as their wood shattered. No sign of wrens, titmice, chickadees. The forest floor was mostly clear. Only a few deer tracks. Most birds and mammals are in hunker-down mode.

Amazingly, given the cold, the springs were still running. This flowing water created some beautiful ice formations on the rocks all around. When water vapor rises from the stream, it hits cold, dry air. This is an unstable mix, ripe for an encounter with a pointy nucleation site: an icy strand of moss or rock edge. Once they get started, these crystals build on themselves, growing “flowers” from the air. An icy foreshadow of the spring ephemerals? The largest ones are a couple of inches across. Similar formations are found in polar seas and host very unusual communities of bacteria.

So welcome to Tennessee, Polar Vortex. Here are your blooms: