Ah ha Man wins again. Way to go Rob. I used to cover the trouble spot or Ice with 8 inches of foam and that stops the frost going super deep. Then heap the snow on top of the foam for a blanket and all will be as snug as a bug. Yes with little snow this year (so far) to insulate the ground stuff happens as the frost goes deeper.
Cheers
Kiwi Just remember we are all watching !!