Q: This ice is raising the dirt and pebbles under this tree. What causes this?

A: These were spotted by my husband under a tree outside his work. They’re ice needles, and they’re pretty cool! They appear to ‘grow’ straight out of the ground. What’s happening is water is drawn up from saturated ground (through capillary action) when temperatures quickly plunge below freezing. They’re very crunchy when stepped on. Also, discover what ‘hoar frost’ is here.