i lived in ND for 4 years and i have no clue how people have chickens there!! i remember you couldnt be outside with ANY skin exposed for longer than a few minutes in the heart of winter. i always called Jan and Feb "the deep freeze" but winter lasted about 6 months there....at least that's how i felt.
oh, and i grew up in Ohio and we had chickens and i remember some of their feet were frozen solid at times. poor things. i remember bringing those ones in and helping them. but even there it was tough on them.