Filters
Penstemon campanulatus (Cav.) Willd.
Penstemon cardwellii T. J. Howell.
Penstemon centranthifolius (Benth.) Benth.
Penstemon cinicola Keck
Penstemon confertus Douglas
Penstemon davidsonii Greene
Penstemon davidsonii Greene var. menziesii (D.D.Keck) Cronquist
Penstemon digitalis Nutt.
Penstemon discolor Keck.
Penstemon duchesnensis (N.H. Holmgren) Neese
Penstemon eatonii A. Gray var. exsertus (A.Nelson) C.C.Freeman
Penstemon eatonii A. Gray ssp. undosus (M.E. Jones) Keck
Penstemon eriantherus Nutt. ex Pursh
Penstemon euglaucus English.
Penstemon floridus Brandeg. var. austinii (Eastw.) N. Holmgren
Penstemon fruticosus (Pursh) Greene
Penstemon fruticosus (Pursh) Greene var. scouleri (Lindley) Cronquist
Penstemon glaber Pursh var. alpinus (Torr.) A.Gray
Penstemon gormanii Greene
Penstemon grinnellii Eastw. var. scrophularioides (M.E. Jones) N.H. Holmgren
Penstemon hallii A. Gray.
Penstemon hartwegii Benth.
Penstemon heterophyllus Lindl.
Penstemon hirsutus (L.) Willd.
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