Graham's beardtongue (Penstemon grahamii)
Detailed Description
Graham's beardtongue (Penstemon grahamii) in the Book Cliffs south of the Uinta Basin, Utah. This species is confined to the Green River Formation, which contains oil shale that is actively mined across the species' range. Photo by Daniel Winkler, SBSC, USGS.
Sources/Usage
Public Domain.