RE: sawdust piles
Being you're from Maine, which i understand gets very cold, i think cardeer's point is valid. One other thing i think could be a reason is the smell. they could be attracted to the smell of that stuff. a pile of sawdust will eventually blow away in the wind and erode, so i dont think deer are directly responsible for this. i think maybe they like the smell of it, as some bucks have been known to rub on cedar trees because of the cedar smell.
slayer