I'll see your forestry act and raise you an ORV act.
Off Road Vehicle Management Framework - Ministry of Forests, Lands and Natural Resource Operations
Amendments to the Forest Service Road Use Regulation (October 2012): a snowmobile operator may cross a ploughed Forest Service Road if they...
What I've been told as well, is that "highways" include any public access roadway and parking lot.
That would mean that if you are parking in a parking lot at a ski resort, or anywhere else that anyone has access to, you REQUIRE that highway insurance. Beyond that, you REQUIRE liability...