Description: English: Flower head close-up cropped from a
Symphyotrichum yukonense specimen collected 11 July 1970 from Kayak shale, about 13 miles due west of Sam Lake, Yukon, Canada, at 2001 feet elevation. Stored at New York Botanical Garden. Date: 18 June 2015. Source:
https://www.gbif.org/occurrence/1929977215. Author: The New York Botanical Garden. Other versions:.