These larger grains, referred to as
depth hoar, result from water vapor depositing or desublimating onto existing snow crystals.
One way of determining the risk of avalanche in any given spot is to dig pits and look for telltale signs of weak layers, such as so-called
depth hoar and surface hoar--freezer-burn-like frost that occurs when snow vaporizes and recrystallizes.
Mountain-top trees shrouded in cold clouds become bottom of every avalanche is
depth hoar, snow recrystallized into a lovely, but perilously weak, honeycomb structure.
7 Grainy, sugarlike
depth hoar crystals will slide and take all the above layers with them if their weak bonds break apart.