Some details to be checked:

The forest is only accessible Dec 1 - Mar 31

(access=no, access:conditional=yes @ (Dec 01 - Mar 31))

A map indicating which paths are private:

https://www.reseaucanopee.org/fr/le-boise-sainte-dorothee/

In fact, the nature reserve 

https://www.openstreetmap.org/way/947392599

might be restricted to this small strip only.

Finally, the vast majority of online sources call it "Bois Sainte Dorothée", not "Le Boisé..."