Eurybia merita

Eurybia merita, commonly known as the subalpine aster or arctic aster (not to be confused with Eurybia sibirica, which shares the latter common name), is an herbaceous perennial native to northwestern North America, primarily from the Interior Mountains and Plateau system and Rocky Mountains in Canada, stretching south to Utah and extreme northern California. It is found largely in drier, open areas, generally at subalpine levels in mountains, though in more northern areas it is more common at lower elevations. It is similar in appearance to Eurybia sibirica, but their ranges only overlap near the border between the US and Canada, where E. sibirica is generally found at higher elevations than its relative. The flowers emerge in the late summer and display purple to violet ray florets and pale or creamy yellow disc florets....read more on Wikipedia.