Dispersed Camping in Ontario Canada

We are planning an extended trip across Southern Ontario and Quebec (from Thunder Bay to Montreal) beginning mid-July.  We would like to spend some of our trip boondock camping but find the rules a little confusing. We were hoping for some feedback from the forum to help clarify where dispersed camping is permitted, regulations for US Citizens and any other helpful resources. The Provincial Parks along the way look wonderful, and we will stay in some, but the cost adds up quickly. Thanks in advance.