What is this large plant? It sprouted up in Alberta Canada without been manually planted.
Google Lens identifies it as Populus lasiocarpa. However, it must be wrong - according to wikipiedia, Populus lasiocarpa is native to China.
I think the ID is close; I would have said cottonwood or Balsam Popular, at least something in the popular/ cottonwood category. They will readily seed themselves. You may have a neighbor that has planted a lasiocarpa and it is now mature enough to produce seed. In some locations with warmer climate ( IL ), it is illegal to plant cotton wood as a landscaping tree.