Here's a cool link:
https://www.ontario.ca/page/stop-spread-invasive-species#section-1
Usually there are many hundreds of identified invasive species identified in a given country, but "The Law" doesn't tend to step in and prohibit something unless the organisms cause significant economic or ecological threat to the state; hence, mulberry and black locust not being on the "heavy-hitters" list, as compared to Zebra mussels or emerald ash borer(threatening the shipping/fishing and timber industries).
Sometimes it is just illegal for vendors to sell or import/export, but not illegal for individuals to own.
Please check the actual local and federal laws before purchase though -
I am not a lawyer and do not presume to give legal advice.
Growing on my small acre in SW USA; Fruit/Nut trees w/ annuals, Chickens, lamb, pigs; rabbits and in-laws onto property soon.
Long term goal - chairmaker, luthier, and stay-at-home farm dad. Check out my music! https://www.youtube.com/@Dustyandtheroadrunners