Ontario Canada or Ontario California?
(There may be other Ontarios)
In each location, I think there will be regulations such as:
On public land (parks, state or national forests etc) probably not permitted.
On private land is probably OK with permission of the owner.
In CA there are some plants that are prohibited in that you cannot be in possession or move them from place to place. I think Hydrilla is one of these.
For regulations in the USA you can start here. I am sure there is similar information available for Canada. Invasive Species: State Laws and Regulations - California