I think for large countries such as the US and Canada, country is too large. For California, county seems best especially since at least plants have full lists by county. For Vermont, which is much smaller and less spatially diverse, state is fine. For looking at the map the towns are great, but for identotron they are nonsensical because they are so small. For Quebec, which goes from maple forest all the way to tundra, some smaller division would be better too, though I am not sure which administrative divisions they most use there. For a smaller country, the whole country may b e fine. Depends on how diverse it is. For instance I imagine a place like Costa Rica that is super diverse with dry and wet areas, you'd want a few divisions.