My understanding is no wood of any kind including sawed, treated, etc. can be taken into Canada.
About 4 years ago at the Port Townsend, WA ferry I asked as I had a small amount of cut lumber. An employee said no lumber of any kind and I could put mine next to the building. When I asked about what they would do with it he said: When they get a cord they auction it off to the employees and the money is donated to a local kids charity. I felt good about that and it was certainly a lot better than dealing with Canadian customs for something that's not allowed.
Years ago the Provincial Parks hired wood cutters to keep the bins full of free firewood. These days you pay for it, at least in my experience.
Several years ago we bought a wheelbarrow full from a kid on Vancouver Island. He and his dad had bought and cut the wood and he was working to repay his dad and then make a profit. What a great way to learn. :B