This association includes natural subalpine vegetation dominated by the tall rhizomatous grass Calamagrostis villosa. Such grasslands are common around and above the timberline, but most of them are rather poor in species. Species-richer stands are mostly found on the upper slopes of glacial cirques, where pronounced snow cover accumulates in winter and protects plants against frost. This vegetation is mainly distributed in the Krkonoše Mountains and rarely in the Hrubý Jeseník Mountains.