OK... So maybe this is a little personal, but he thought long and hard about this one so I had to tell the story.
After the blizzard we had a lot of snow in the back yard. A lot of it was over his head so he couldn't make it through.
We let him out during the day and he would pee on the snow banks along the drive way or play in the deep snow.
I knew he had to poop when he kept looking into the back yard. He looked and pondered then walked around a little.
Finally he found a place in the drive way that was dirty from where the truck had been parked. He pooped right on the dirtiest spot of snow.
He has such good judgement. What a good boy.