Hoar frost on dead lodgepole pine trees
I made this image one autumn morning, at Terrace Spring near the Gibbon River in Yellowstone National Park.
Terrace Spring is a thermal feature in the park that produces a lot of steam.
Hoar frost occurs when that steam condenses and freezes in air of low humidity and usually during cold nights.
Up close the hoar frost crystals look like little white needles, but once the morning sun warms the frost, it doesn’t take long to melt.
In minutes the sharp, showy white ice, vanishes.