Places you can't " boondock" are in any provincial or national park. There are lots of places beside a hwy or up a logging road that is just fine, however on active logging roads your going to have company in the way of logging trucks going back and forth as well as all the people and equipment that go with them. Plus if you don't have a 2-way radio with the logging truck frequency that they are using your going to most likely meet up with a loaded logging truck thundering down the road coming right at you. Active logging roads have large signs at the start of the road that will identify the frequency that you should monitor when on the roads.
I know in the are around where we live there are lots of places beside the Hwy that a person could pull over and park for the night however your right beside a Hwy.
Here is a good link to safe traveling on logging roads
Logging road safety tipsSoup