Filters
Penstemon hirsutus (L.) Willd. 'Pygmaeus'
Penstemon hirsutus (L.) Willdenow 'Albiflorus'
Penstemon humilis Nutt. ex A. Gray.
Penstemon janishiae N. Holmgren
Penstemon laevigatus Aiton
Penstemon linarioides Gray var. coloradoensis (A.Nelson) C.C.Freeman
Penstemon linarioides Gray var. sileri A. Gray
Penstemon lyallii (A.Gray) A.Gray
Penstemon mensarum Pennell
Penstemon neomexicanus Wooton & Standley
Penstemon neotericus Keck
Penstemon newberryi A. Gray.
Penstemon palmeri A.Gray var. eglandulosus (Keck) N. Holmgren
Penstemon parvulus (Gray) Krautt.
Penstemon pennellianus Keck
Penstemon pinifolius Greene.
Penstemon pinifolius Greene. 'Mersea Yellow'
Penstemon procerus Douglas ex Graham
Penstemon procerus Douglas ex Graham var. brachyanthus (Pennell) Cronquist
Penstemon procerus Douglas ex Graham var. tolmiei (Hook.) Cronquist
Penstemon pruinosus Douglas
Penstemon purpusii Brand.
Penstemon richardsonii Douglas ex Lindl.
Penstemon roseus (Cerv. ex Sweet) G.Don
Penstemon rostriflorus Kellogg.
Penstemon rupicola (Piper) Howell.
Penstemon rupicola (Piper) Howell. 'Alba'
Penstemon rupicola (Piper) Howell. 'Karol'
Penstemon rydbergii A.Nelson var. oreocharis (Greene) N. Holmgren
Penstemon serrulatus Menzies ex Sm.