What I do is I collect bagged leaves in the fall (LOTS of them), then after a snowstorm I shovel what I can, and then spread dry leaves on the ground for the chickens to walk on. Mine refuse to set foot on snow, but they LOVE the dry leaves, even if there's some snow underneath. They entertain themselves by scratching around and churning the ground until everything is mixed in - leaves, run litter and some snow - and it's no big deal for them to step on anymore. I also have very loose run litter that drains well and doesn't freeze solid. It's a mix of wood chips and various yard waste collected throughout the year, depending on the season - raked stuff from the yard's spring cleanup, grass clippings from the summer's lawn mowings, dry leaves from the fall, etc. It doesn't get muddy or stay wet, which means that it doesn't freeze solid in winter either. So no ice. I'm in Boston and we can get brutal snowstorms and hard freezes sometimes, but I haven't had an ice problem in the run so far. Just lots of snow to shovel, but once I get down to the run litter, and throw fresh leaves on top, we're good.