Bill Bouton:
Foothill Penstemon/Beardtongue, Penstemon heterophyllus
Bill Bouton:
Foothill Penstemon, Penstemon heterophyllus
Bill Bouton:
Foothill/Bunchleaf Penstemon, Penstemon heterophyllus
Bill Bouton:
Foothill/Bunchleaf Penstemon, Penstemon heterophyllus
Bill Bouton:
Low Beardstongue, Penstemon h. humilis
Bill Bouton:
Royal Beardtongue/Royal Penstemon, Penstemon speciosus
Bill Bouton:
Royal Beardtongue/Royal Penstemon, Penstemon speciosus
Bill Bouton:
Alberta Penstemon, Penstemon albertinus
Bill Bouton:
Mountain Pride/Newberry's Penstemon, Penstemon newberryi
Bill Bouton:
Grinnell's Beardtongue, Penstemon grinnellii
Bill Bouton:
Fuzzytongue Penstemon, Penstemon eriantherus
Bill Bouton:
Fuzzytongue Penstemon, Penstemon eriantherus
Bill Bouton:
San Gabriel Beardtongue, Penstemon labrosus
Bill Bouton:
San Gabriel Beardtongue, Penstemon labrosus
Bill Bouton:
Heart Leaved Penstemon, Keckiella cordifolia
Bill Bouton:
Heart Leaved Penstemon, Keckiella cordifolia
Bill Bouton:
Scarlet Bugler, Penstemon centranthifolius
Bill Bouton:
Rydberg's/Meadow Penstemon, Penstemon rydbergii (?); ID confirmation appreciated
Bill Bouton:
Pinyon Beardtongue, Penstemon scapoides