I've only had to deal with a plow once. I was in a rural part of Indiana, I saw the plow coming up from behind. There was no shoulder, just a guardrail and an embankment down to a creek. I stopped the bike, jumped off, over the guard rail, lifted the bike, and pulled it over the guardrail.

This way the bike and I were both on the other side of the guardrail. The plow driver waved as he went by, then I had clear roads for the rest of the ride.