I live in South East Minnesota. My chickens live in a small-ish coop (>>>Completely unintentionally this worked out well- I have a 6x9 coop for my 22 chickens, which is on the small side, but it has a "second floor" of another 18 sq feet... and with all the snow we get and their obvious distaste for the substance I learned fast that wasn't going to be enough space for my chickens. So I built a 10 by 10 A frame and covered it with a heavy duty canvas tarp... seriously, this took me 4 hours to build and the biggest expense was the tarp... and butted it up to their pop door. The moral of the story being that they have 178 square feet of sheltered, usable, snow free space during the day, but at night they're confined to the smaller, more secure coop that helps concentrate their heat by keeping them to a warmer space... anyway...<<<) with lots of eave ventilation and a 2x4 window that I open any day the temp is above freezing (and there isn't serious wind) and close at night. It's dry here in the winter, so with my ventilation it's a pretty fair bet that humidity isn't a huge issue. That's a lot of info for a simple question- when do I know it's time to put vaseline on my roosters' combs? I have a BO rooster with a HUGE comb (huge...) and a Wyandotte with a nearly as huge comb. And at what point do I start to worry about the hens' combs? With their smaller combs the hens are less susceptible but not out of the woods, right? So anyone else who deals with regular single digit and sub zero temps, how do you know when to bust out the vaseline? Because I really don't want to learn this the hard way, but I also really don't want to vaseline both of my boys every night for the next four months.