The main criterion for the delimitation of this habitat type is the character of the vegetation which must allow for a clear assignment to the communities of the Polygono-Trisetion or the Poion alpinae respectively. Mountain hay meadows are taken to be species-rich if they are typical of the relevant plant community and contain a high number of characteristic species. The presence of species alien to the syntaxonomic unit e.g. in fallows should not be considered as adding to species-richness. If the sites contain typical species suites meadows with aftergrass or early fallow stages may be considered for inclusion.