Answer:
The landform that provides the trees/lumber that is used to power Quebec and Ontario's economy is the Canadian Shield.
Step-by-step explanation:
Quebec and Ontario are Canadian provinces. They are the top two or close to the top in pretty much every department in Canada. They have a lot of natural resources, they have the highest populations, their economies are the most developed, etc. One natural resource that is extremely important for the economy of these two is the lumber or rather the forests.
The Canadian Shield, which is the most dominant landform in Canada, occupies almost all of the territories of these two provinces. It is the landform that actually provides all of the trees/lumber. The forests are boreal, and the majority of them made up of coniferous trees, though in the southern parts there are multiple species of trees that are deciduous, like Canada's trademark tree - the maple, which is also a tree that brings in a lot of profit to these provinces and the country as a whole.