I happened upon this discussion of vernacular plant names, and felt I needed to clarify a couple of things regarding the Swedish Taxonomy Initiative (Svenska Artprojektet). The work that is carried out by their naming committees is not an attempt to create "the one true Swedish name". They are just choosing the names, which are going to be used as the Swedish standard within the inventory project, and in particular in the book series Nationalnyckeln (Encyclopedia of the Swedish Flora and Fauna), with a recommendation to others to use the same names, in order to improve communication. However, this does not mean that other, alternative names are forbidden. There is absolutely no regulation, legal or otherwise, of vernacular names, either in Sweden or in any other EU country. There are only agreements to come up with "official" standard names to improve communication in non-scientific contexts. Anyone can choose to ignore them, and use other names instead. Like someone wrote above, if you invent a name and others start using it too, then it's a vernacular name (not the vernacular name). Furthermore, the naming work within the Swedish project, doesn't just involve picking a name among those already in use. As far as possible they choose the most common and established name, but if this is inappropriate for some reason (misleading, inordinately long, likely to cause confusion etc.), another name is chosen or invented. Most Swedish species, however, doesn't have any vernacular names, so the work largely involves inventing new names, which preferably should say something informative about the species in question (colour, behaviour, habitat etc.). The only groups where all Swedish species have traditional vernacular names are vascular plants, butterflies and vertebrates. Then there are groups where many, but far from all, species have such names, eg. fungi and beetles. All other names have been invented by committees or authors of field guides and the like. This is the only reason why all Swedish mosses have common names; traditionally, only a few easily recognisable and/or culturally important species had names.