Hi Dylan,

I have now downloaded official CanVec data from the "Government of Canada"  website and its "Geospatial Extraction Tool" at 1:50k scale from one of the areas you recently added to OSM, to be able to compare the imported data with the official data.

I then loaded it in ArcGIS to have a look at the data. I learned two important things from this:

- CanVec data uses a classification for the density of the forest with four classes: 'Forest','Dense','Open' and 'Sparse'. You are undoubtedly already aware of this, but it definitely seems anything classified as 'Open' or 'Sparse' should not be imported as woodland in OpenStreetMap. Such often waterlogged and bog type acidic environments with sparse trees because few can survive, would not qualify.

- There is definitely an issue with your current workflow. The 'whitish' tiles with few forest polygons, seem to properly match 'Forest' and 'Dense' classifications, and seem OK. The almost entirely green tiles, where the entire tile was imported as woodland, seem wrong, they don't match.

I wrapped up a direct comparison in a screenshot of exactly the same area in OSM and ArcGIS, including a quick legend for the official CanVec data in ArcGIS, that shows the different classifications and issues, see the below DropBox link where you can download it:
https://www.dropbox.com/scl/fi/3tekmykdwwp7vdxlj0xxu/Canvec_issue.png?rlkey=z6x7p3h6hgtbrya6iwtkg5bnx&dl=0

There is now also a tough decision to make. It may be hard to fix this in any (semi-)automated manner. Maybe you need to revert the entire import of all of these tiles, and start from scratch after you've corrected your workflow and are absolutely sure it will now produce proper results.