Penstemon Speciosus1

''Penstemon'' , the beardtongues, is a large genus of roughly 250 species of flowering plants native mostly to the Nearctic, but with a few species also found in the North American portion of the Neotropics. It is the largest genus of flowering plants endemic to North America. Formerly placed in the family Scrophulariaceae by the Cronquist system, new genetic research has placed it in the vastly expanded family Plantaginaceae.

They have opposite leaves, partly tube-shaped, and two-lipped flowers and seed capsules. The most distinctive feature of the genus is the prominent staminode, an infertile stamen. The staminode takes a variety of forms in the different species; while typically a long straight filament extending to the mouth of the corolla, some are longer and extremely hairy, giving the general appearance of an open mouth with a fuzzy tongue protruding and inspiring the common name beardtongue.

Most penstemons are deciduous or semi-evergreen perennials, the remainder being shrubs or subshrubs. Heights can range from 10 cm to as much as 3 metres.

The one Asiatic species previously treated in ''Penstemon'' is now placed in a separate genus ''Pennellianthus''. This leaves ''Penstemon'' a mostly Nearctic genus, with a few neotropical species. Although widespread across North America, and found in habitats ranging from open desert to moist forests, and up to the alpine zone, they are not typically common within their range.

History

John Mitchell published the first scientific description in 1748; although he only named it as ''Penstemon'', we can identify it as '' P. laevigatus''. Linnaeus then included it in his 1753 publication, as ''Chelone pentstemon'', altering the spelling to better correspond to the notion that the name referred to the unusual fifth stamen (Greek "penta-", five). Mitchell's work was reprinted in 1769, continuing with his original spelling, and this was ultimately accepted as the official form, although ''Pentstemon'' continued in use into the 20th century.

Although several more species were found in the 18th century, they continued to be classified in '' Chelone'' until about the 1820s. The period of 1810 to 1850 increased the number of known species from 4 to 63, as expeditions traveled through Mexico and the western United States, followed by another 100 up to 1900.

During this time, seeds began to be offered for sale in Europe, the earliest known dating from 1813, with John Fraser offering four species in London, followed by Flanagan & Nutting offering nine species in their 1835 catalog. Subsequently many hybrids were developed in Europe.

Fieldwork in the remote parts of the Great Basin during the 20th century brought the total number of species known to over 250. The genus was extensively revised by David Keck between 1932 and 1957.

In 1946 the American Penstemon Society (link at bottom) was formed to promote both horticultural and botanical interest.

Uses

Some Native American tribes used penstemons as medicinal remedies for humans and animals.Escamilla, G., et al
''Penstemon ambiguus''.
Medicinal Plants of the Southwest. New Mexico State University. 2001. Updated 2008. Today its primary use is ornamental.

Horticulture

Although penstemons are among the most attractive native flowers of North America, Europe has traditionally been far more active in their hybridization with hundreds of hybrids developed since the early 19th century. The earliest development is somewhat shrouded in mystery; for instance Flanagan & Nutting's 1835 catalog mentions a 'Penstemon Hybridum' but does not describe it.

By 1860, a half-dozen French growers are known to have developed hybrids, most notably Victor Lemoine, while in 1857 the German Wilhelm Pfitzer listed 24 varieties. In 1861 the British Royal Horticultural Society held trials in which 78 varieties were entered. The Scottish firm of John Forbes first offered penstemons in 1870, eventually becoming the biggest grower in the world; in 1884 their catalog listed 180 varieties. By 1900 Forbes had offered 550 varieties, while Lemoine had developed nearly 470 by the time of his death in 1911. Few of these have survived to the present day.

A number of different species have been used in the hybridization process, notably '' P. cobaea'' and '' P. hartwegii''.

In North America, penstemons are often used in xeriscape landscaping, as many are native to desert or alpine regions and thus quite hardy. One of the largest collections of penstemons in North America is found at The Arboretum at Flagstaff, Arizona, which hosts a Penstemon Festival each summer.

Cultivars

The following species and cultivars have gained the Royal Horticultural Society's Award of Garden Merit:-

* 'Andenken an Friedrich Hahn' (deep red)

* 'Beech Park' (pink/white)

* 'Connie's Pink' (rose pink)
* 'Evelyn' (rose pink)
* 'George Home' (red/white)
* 'Hewell Pink Bedder' (pink/white)
* ' Hidcote Pink'
* 'Margery Fish' (purple/blue)
* 'Maurice Gibbs' (purple-red/white)
* 'Osprey' (pink/white)
* ''P. hartwegii'' (scarlet)
* ''P. isophyllus'' (pale pink)
* ''P. pinifolius'' 'Wisley Flame' (orange-red)
* ''P. rupicola'' (pink)

* 'Port Wine' (deep red/white)
* 'Raven' (purple/white)
* 'Rich Ruby'
* 'Roy Davidson' (pink/white)
* 'Rubicundus' (red/white)
* 'Schoenholzeri' (red)
* 'Sour Grapes' (purple/blue)
* 'Stapleford Gem' (purple/blue)

Others include 'Dark Towers', developed by Dale Lindgren at the University of Nebraska.

Species

* '' Penstemon abietinus'' Pennell – Firleaf beardtongue
* '' Penstemon absarokensis'' Evert – Absaroka Range beardtongue
* '' Penstemon acaulis'' L.O. Williams – Stemless beardtongue
* '' Penstemon acuminatus'' Dougl. ex Lindl. – Sharpleaf penstemon
* '' Penstemon alamosensis'' Pennell & Nisbet – Los Alamos beardtongue
* '' Penstemon albertinus'' Greene – Alberta beardtongue
* '' Penstemon albidus'' Nutt. – White penstemon
* ''Penstemon albomarginalis'' M. E. Jones
* '' Penstemon albomarginatus'' M.E. Jones – White margin penstemon, whitemargin beardtongue, whitemargin penstemon
* '' Penstemon alluviorum'' Pennell – lowland beardtongue
* '' Penstemon ambiguus'' Torr. – bush penstemon, gilia beardtongue, gilia penstemon
* '' Penstemon ammophilus'' N. Holmgren & L. Shultz – sandloving penstemon
* '' Penstemon anguineus'' Eastw. – Siskiyou beardtongue
* '' Penstemon angustifolius'' Nutt. ex Pursh – broad-beard beardtongue, broadbeard beardtongue, narrowleaf penstemon
* '' Penstemon arenarius'' Greene – Nevada sanddune beardtongue, sanddune penstemon
* '' Penstemon arenicola'' A. Nels. – sand penstemon
* '' Penstemon aridus'' Rydb. – stiffleaf penstemon
* '' Penstemon arkansanus'' Pennell – Arkansas beardtongue
* '' Penstemon attenuatus'' Dougl. ex Lindl. – sulphur penstemon
* '' Penstemon atwoodii'' Welsh – Kaiparowits beardtongue
* '' Penstemon auriberbis'' Pennell – Colorado beardtongue
* '' Penstemon australis'' Small – Eustis Lake beardtongue
* '' Penstemon azureus'' Benth. – azure penstemon
* '' Penstemon baccharifolius'' Hook. – baccharisleaf beardtongue Francis Whittier Pennell
* '' Penstemon barbatus'' (Cav.) Roth – Golden-beard Penstemon or Beardlip penstemon
* '' Penstemon barnebyi'' N. Holmgren – Barneby's penstemon, White River Valley beardtongue
* '' Penstemon barrettiae'' Gray – Barrett's beardtongue
* '' Penstemon bicolor'' (Brandeg.) Clokey & Keck – pinto beardtongue, pinto penstemon
* '' Penstemon bracteatus'' Keck – Red Canyon beardtongue
* '' Penstemon breviculus'' (Keck) Nisbet & R.C. Jackson – shortstem beardtongue, shortstem penstemon
* '' Penstemon brevisepalus'' Pennell – short-sepaled beardtongue
* ''Penstemon bryantiae'' Keck – Bryant's beardtongue
* '' Penstemon buckleyi'' Pennell – buckley penstemon, Buckley's beardtongue
* '' Penstemon caesius'' Gray – San Bernardino beardtongue
* '' Penstemon caespitosus'' Nutt. ex Gray – mat penstemon
* '' Penstemon calcareus'' Brandeg. – limestone beardtongue
* '' Penstemon californicus'' (Munz & Johnston) Keck – California penstemon
* '' Penstemon calycosus'' Small – longsepal beardtongue
* '' Penstemon campanulatus'' (Cav.) Willd. – bellflower beardtongue
* '' Penstemon canescens'' (Britt.) Britt. – eastern gray beardtongue
* '' Penstemon cardinalis'' Woot. & Standl. – cardinal beardtongue
* '' Penstemon cardwellii'' T.J. Howell – Cardwell's beardtongue
* '' Penstemon carnosus'' Pennell – fleshy beardtongue
* '' Penstemon caryi'' Pennell – Cary's beardtongue
* ''Penstemon cedrosensis''
* '' Penstemon centranthifolius'' Benth. – scarlet bugler
* '' Penstemon cinicola'' Keck – ash penstemon
* '' Penstemon cleavelandii'' Gray
* '' Penstemon clevelandii'' Gray – Cleveland's beardtongue
* '' Penstemon clutei'' A. Nels. – Sunset Crater beardtongue, Sunset Crater penstemon
* '' Penstemon cobaea'' Nutt. – cobaea beardtongue, Cobaea penstemon
* '' Penstemon comarrhenus'' Gray – dusty beardtongue, dusty penstemon
* '' Penstemon compactus'' (Keck) Crosswhite – compact penstemon
* '' Penstemon concinnus'' Keck – Tunnel Springs beardtongue, Tunnel Springs penstemon
* '' Penstemon confertus'' Dougl. ex Lindl. – yellow penstemon
* '' Penstemon confusus'' M.E. Jones – Owens Valley beardtongue, Owens Valley penstemon
* '' Penstemon crandallii'' A. Nels. – Crandall's beardtongue
* '' Penstemon crideri'' A. Nels. (pro sp.) – Crider penstemon, Crider's penstemon
* '' Penstemon cusickii'' Gray – Cusick's beardtongue
* '' Penstemon cyananthus'' Hook. – Wasatch beardtongue
* '' Penstemon cyaneus'' Pennell – blue penstemon
* '' Penstemon cyanocaulis'' Payson – bluestem beardtongue
* '' Penstemon cyathophorus'' Rydb. – Northpark penstemon, sagebrush beardtongue
* '' Penstemon dasyphyllus'' Gray – Cochise beardtongue, purple penstemon
* '' Penstemon davidsonii'' Greene – Davidson's penstemon, timberline penstemon
** ''Penstemon davidsonii'' var. ''davidsonii'' – Davidson's penstemon
** ''Penstemon davidsonii'' var. ''menziesii'' – Menzies' penstemon
** ''Penstemon davidsonii'' var. ''praeteritus'' – timberline penstemon
* '' Penstemon deamii'' Pennell – Deam's beardtongue
* '' Penstemon deaveri'' Crosswhite – Mt. Graham beardtongue
* '' Penstemon debilis'' O'Kane & J. Anderson – Parachute beardtongue
* '' Penstemon degeneri'' Crosswhite – Degener's beardtongue
* '' Penstemon deustus'' Dougl. ex Lindl. – scabland penstemon
* '' Penstemon digitalis'' Nutt. ex Sims – talus slope penstemon, foxglove beardtongue
* '' Penstemon diphyllus'' Rydb. – twoleaf beardtongue
* '' Penstemon discolor'' Keck – Catalina beardtongue
* '' Penstemon dissectus'' Ell. – dissected beardtongue
* '' Penstemon distans'' N. Holmgren – Mt. Tumbull beardtongue
* '' Penstemon dolius'' M.E. Jones ex Pennell – Jones's penstemon, Jones' beardtongue
* '' Penstemon dubius'' A. Davids. (pro sp.) – dubius penstemon
* '' Penstemon eatonii'' Gray – Eaton penstemon, Eaton's penstemon, firecracker penstemon
* '' Penstemon elegantulus'' Pennell – rockvine penstemon
* '' Penstemon ellipticus'' Coult. & Fisher – rocky ledge penstemon
* '' Penstemon eriantherus'' Pursh – fuzzytongue penstemon
* '' Penstemon euglaucus'' English – glaucous beardtongue
* '' Penstemon eximius'' Keck – unusual beardtongue
* '' Penstemon fendleri'' Torr. & Gray – fendler penstemon, Fendler's beardtongue, Fendler's penstemon
* '' Penstemon filiformis'' (Keck) – Keck threadleaf beardtongue
* '' Penstemon flavescens'' Pennell – high mountain penstemon
* '' Penstemon floribundus'' D. Danley – Cordillia's beardtongue, Cordillia's penstemon
* '' Penstemon floridus'' Brandeg. – Panamint beardtongue, Panamint penstemon
* '' Penstemon flowersii'' Neese & Welsh – Flowers' beardtongue
* '' Penstemon franklinii'' Welsh – Franklin's penstemon
* '' Penstemon fremontii'' Torr. & Gray ex Gray – Fremont penstemon, Fremont's beardtongue
* '' Penstemon fruticiformis'' Coville – Death Valley beardtongue, Death Valley penstemon
* '' Penstemon fruticosus'' (Pursh) – Greene bush penstemon
* ''Penstemon gairdneri'' Hook. – Gairdner's beardtongue
* '' Penstemon gibbensii'' Dorn – Gibbens' beardtongue
* '' Penstemon glaber'' Pursh – sawsepal penstemon, western smooth beardtongue
* '' Penstemon glandulosus'' Dougl. – stickystem penstemon
* '' Penstemon glaucinus'' Pennell – blueleaf beardtongue
* '' Penstemon globosus'' (Piper) Pennell & Keck – globe penstemon
* '' Penstemon goodrichii'' N. Holmgren – Lapoint beardtongue
* ''Penstemon gormanii'' Greene – Gorman's beardtongue
* '' Penstemon gracilentus'' Gray – slender penstemon
* '' Penstemon gracilis'' Nutt. – lilac penstemon, slender penstemon
* '' Penstemon grahamii'' Keck – Uinta Basin beardtongue
* '' Penstemon grandiflorus'' Nutt. – large beardtongue, largeflowered penstemon
* '' Penstemon griffinii'' A. Nels. – Griffin's beardtongue
* '' Penstemon grinnellii'' Eastw. – Grinnell's beardtongue
* '' Penstemon guadalupensis'' Heller – Guadalupe beardtongue
* '' Penstemon hallii'' Gray – Hall's beardtongue
* '' Penstemon harbourii'' Gray – Harbour's beardtongue
* '' Penstemon harringtoni'' Penl.
* ''Penstemon harringtonii'' Penl. – Harrington's beardtongue
* '' Penstemon hartwegii'' Benth. – Hartweg's beardtongue
* '' Penstemon harvardii'' Gray
* '' Penstemon havardii'' Gray – Big Bend beardtongue
* '' Penstemon haydenii'' S. Wats. – blowout beardtongue, blowout penstemon
* '' Penstemon heterodoxus'' Gray – Sierra beardtongue, Sierra penstemon
* '' Penstemon heterophyllus'' Lindl. – bunchleaf penstemon
* '' Penstemon hirsutus'' (L.) Willd. – hairy beardtongue
* '' Penstemon humilis'' Nutt. ex Gray – low beardtongue, low penstemon
* '' Penstemon idahoensis'' Atwood & Welsh – Idaho beardtongue
* '' Penstemon immanifestus'' N. Holmgren – Steptoe Valley beardtongue, Steptoe Valley penstemon
* ''Penstemon incertus'' Brandeg. – Mojave beardtongue
* '' Penstemon inflatus'' Crosswhite – inflated beardtongue
* '' Penstemon jamesii'' Benth. – James penstemon, James' beardtongue
* '' Penstemon janishiae'' N. Holmgren – Antelope Valley beardtongue, Janish's penstemon
* '' Penstemon jonesi'' Pennell
* '' Penstemon jonesii'' Pennell (pro sp.) – Jones' penstemon
* ''Penstemon kingii'' S. Wats. – King's beardtongue, King's penstemon
* '' Penstemon labrosus'' (Gray) Hook. f. – San Gabriel beardtongue
* '' Penstemon laetus'' Gray – mountain blue penstemon
* '' Penstemon laevigatus'' Ait. – eastern smooth beardtongue
* '' Penstemon laevis'' Pennell – southwestern beardtongue, southwestern penstemon
* '' Penstemon laricifolius'' Hook. & Arn. – larchleaf beardtongue
* '' Penstemon laxiflorus'' Pennell – nodding beardtongue
* '' Penstemon laxus'' A. Nels. – tufted penstemon
* '' Penstemon leiophyllus'' Pennell – smoothleaf beardtongue, smoothleaf penstemon
* '' Penstemon lemhiensis'' (Keck) Keck & Cronq. – Lemhi penstemon
* '' Penstemon lentus'' Pennell – handsome beardtongue, handsome penstemon
* '' Penstemon leonardii'' Rydb. – Leonard's beardtongue, Leonard's penstemon
* ''Penstemon leptanthus'' Pennell – Sevier Plateau beardtongue
* '' Penstemon linarioides'' Gray – creeping penstemon, toadflax penstemon
* '' Penstemon longiflorus'' (Pennell) S.L. Clark – longflower penstemon
* '' Penstemon lyallii'' (Gray) Gray – Lyall's beardtongue
* '' Penstemon marcusii'' (Keck) N. Holmgren – Marcus' beardtongue
* '' Penstemon mensarum'' Pennell – tiger beardtongue
* '' Penstemon metcalfei'' – Metcalfe's beardtongue
* '' Penstemon mirus'' A. Nels. (pro sp.) – bush penstemon, penstemon
* '' Penstemon miser'' Gray – Malheur penstemon
* '' Penstemon moffatii'' Eastw. – Moffatt's beardtongue
* '' Penstemon monoensis'' Heller – Mono penstemon
* '' Penstemon montanus'' Greene – cordroot beardtongue
* '' Penstemon moriahensis'' N. Holmgren – Mount Moriah penstemon, Mt. Moriah beardtongue
* '' Penstemon multiflorus'' Chapman ex Benth. – manyflower beardtongue
* '' Penstemon murcronatus'' N. Holmgr.
* '' Penstemon murrayanus'' Hook. – scarlet beardtongue
* '' Penstemon nanus'' Keck – dwarf beardtongue
* '' Penstemon navajoa'' N. Holmgren – Navajo Mountain beardtongue
* '' Penstemon neomexicanus'' Woot. & Standl. – New Mexico beardtongue
* ''Penstemon neotericus'' Keck – Plumas County beardtongue

* '' Penstemon newberryi'' Gray – mountain pride, pride-of-the-mountains
* '' Penstemon nitidus'' Dougl. ex Benth. – waxleaf penstemon
* '' Penstemon nudiflorus'' Gray – Flagstaff beardtongue
* '' Penstemon oklahomensis'' Pennell – Oklahoma beardtongue, Oklahoma penstemon
* '' Penstemon oliganthus'' Woot. & Standl. – Apache beardtongue
* '' Penstemon ophianthus'' Pennell – Arizona beardtongue, coiled anther penstemon
* '' Penstemon osterhoutii'' Pennell – Osterhout's beardtongue
* '' Penstemon ovatus'' Dougl. ex Hook. – eggleaf beardtongue
* '' Penstemon pachyphyllus'' Gray ex Rydb. – thickleaf beardtongue, thickleaf penstemon
* '' Penstemon pahutensis'' N. Holmgren – Pahute penstemon, Paiute beardtongue
* '' Penstemon pallidus'' Small – pale beardtongue
* ''Penstemon palmeri'' Gray – Palmer's penstemon, Palmer penstemon
* '' Penstemon papillatus'' J.T. Howell – Inyo beardtongue
* '' Penstemon parishii'' Gray (pro sp.) – Parish's penstemon
* '' Penstemon parryi'' (Gray) – Gray Parry penstemon, Parry's beardtongue
* '' Penstemon parviflorus'' Pennell – Montezuma County beardtongue
* '' Penstemon parvus'' Pennell – Aquarius Plateau beardtongue
* '' Penstemon patens'' (M.E. Jones) N. Holmgren – Lone Pine beardtongue, Lone Pine penstemon
* '' Penstemon payettensis'' A. Nels. & J.F. Macbr. – Payette beardtongue
* '' Penstemon paysoniorum'' Keck – Payson's beardtongue
* ''Penstemon peckii'' Pennell – Peck's beardtongue
* '' Penstemon peirsonii'' Munz & I.M. Johnston (pro sp.) – Peirson's penstemon
* '' Penstemon penlandii'' W.A. Weber – penland beardtongue, Penland's beardtongue
* '' Penstemon pennellianus'' Keck – Blue Mountain beardtongue
* '' Penstemon perpulcher'' A. Nels. – Minidoka beardtongue
* '' Penstemon personatus'' Keck – closethroat beardtongue
* '' Penstemon petiolatus'' Brandeg. – lime penstemon, petiolate beardtongue
* '' Penstemon pinifolius'' Greene – pineneedle beardtongue, pineneedle penstemon
* '' Penstemon pinorum'' L.& J. Shultz – Pine Valley penstemon
* '' Penstemon platyphyllus'' Rydb. – broadleaf beardtongue, broadleaf penstemon
* '' Penstemon pratensis'' Greene western – whiteflower beardtongue, western whiteflower penstemon
* '' Penstemon procerus'' Dougl. ex Graham – littleflower penstemon, pincushion beardtongue
* '' Penstemon pruinosus'' Dougl. ex Lindl. – Chelan beardtongue
* '' Penstemon pseudoparvus'' Crosswhite – Mt. Washington beardtongue, San Mateo penstemon
* '' Penstemon pseudoputus'' (Crosswhite) N. Holmgren – Kaibab Plateau beardtongue
* '' Penstemon pseudospectabilis'' M.E. Jones – desert penstemon
* '' Penstemon pudicus'' Reveal & Beatley – bashful penstemon, Kawich Range beardtongue
* '' Penstemon pumilus'' Nutt. – Salmon River beardtongue
* '' Penstemon purpusii'' Brandeg. – Snow Mountain beardtongue
* '' Penstemon putus'' A. Nels. – Black River beardtongue
* '' Penstemon radicosus'' A. Nels. – matroot penstemon
* '' Penstemon ramosus'' Crosswhite – lanceleaf beardtongue, lanceleaf penstemon
* '' Penstemon rattanii'' Gray – Rattan's beardtongue
* '' Penstemon retrorsus'' Payson ex Pennell – Adobe Hills beardtongue
* '' Penstemon retrosus'' Payson ex Pennell
* '' Penstemon rhizomatosus'' N. Holmgren
* '' Penstemon richardsonii'' Dougl. ex Lindl. – cutleaf beardtongue
* '' Penstemon roezlii'' Regel – Roezl's penstemon
* '' Penstemon rostriflorus'' Kellogg – beaked beardtongue, beakflower penstemon, Bridge penstemon
* '' Penstemon rubicundus'' Keck – Wassuck penstemon, Wassuk Range beardtongue
* '' Penstemon rupicola'' (Piper) T.J. Howell – cliff beardtongue
* ''Penstemon rydbergii'' A. Nels. – meadow beardtongue, Rydberg penstemon, Rydberg's penstemon
* '' Penstemon saxosorum'' Pennell – upland beardtongue
* '' Penstemon scapoides'' Keck – pinyon beardtongue
* '' Penstemon scariosus'' Pennell – White River beardtongue
* '' Penstemon secundiflorus'' Benth. – sidebells penstemon
* '' Penstemon seorsus'' (A. Nels.) Keck – shortlobe penstemon
* '' Penstemon sepalulus'' A. Nels. – littlecup beardtongue
* '' Penstemon serrulatus'' Menzies ex Sm. – serrulate penstemon
* '' Penstemon smallii'' Heller – Small's beardtongue
* '' Penstemon spatulatus'' Pennell – Wallowa beardtongue
* '' Penstemon speciosus'' Dougl. ex Lindl. – prairie-clover, royal penstemon
* ''Penstemon spectabilis'' Thurb. ex Gray – showy penstemon
* '' Penstemon stenophyllus'' (Gray) T.J. Howell – Sonoran beardtongue
* '' Penstemon stephensii'' Brandeg. – Stephens' penstemon
* '' Penstemon strictiformis'' Rydb. – Mancos penstemon, stiff penstemon
* ''Penstemon strictus'' Benth. – Rocky Mountain beardtongue, Rocky Mountain penstemon
* '' Penstemon subglaber'' Rydb. – smooth penstemon
* '' Penstemon subserratus'' Pennell – finetooth beardtongue
* '' Penstemon subulatus'' M.E. Jones – hackberry beardtongue
* '' Penstemon sudans'' M.E. Jones – Susanville beardtongue, Susanville penstemon
* '' Penstemon superbus'' A. Nels. – superb beardtongue
* '' Penstemon tenuiflorus'' Pennell – eastern whiteflower beardtongue
* '' Penstemon tenuis'' Small – sharpsepal beardtongue
* '' Penstemon teucrioides'' Greene – germander beardtongue
* '' Penstemon thompsoniae'' (Gray) Rydb. – Thompson's penstemon, Thompson's beardtongue, Thompson penstemon
* '' Penstemon thurberi'' Torr. – Thurber's penstemon, Thurber penstemon
* '' Penstemon tidestromii'' Pennell – Tidestrom's beardtongue
* '' Penstemon tiehmii'' N. Holmgren – Tiehm's beardtongue
* '' Penstemon tracyi'' Keck – Trinity penstemon
* ''Penstemon triflorus'' Heller – Heller's beardtongue
* '' Penstemon triphyllus'' Dougl. ex Lindl. – Riggin's penstemon
* '' Penstemon tubaeflorus'' Nutt. – white wand beardtongue
* '' Penstemon tusharensis'' N. Holmgren – Tushar Range beardtongue
* '' Penstemon uintahensis'' Pennell – Uinta Mountain beardtongue
* '' Penstemon unilateralis'' Rydb. – oneside penstemon
* '' Penstemon utahensis'' Eastw. – Utah penstemon
* '' Penstemon venustus'' Dougl. ex Lindl. – Venus penstemon
* '' Penstemon virens'' Pennell ex Rydb. – Front Range beardtongue
* '' Penstemon virgatus'' Gray – upright blue beardtongue
* '' Penstemon wardii'' Gray – Ward's beardtongue
* '' Penstemon washingtonensis'' Keck – Washington beardtongue
* '' Penstemon watsonii'' Gray – Watson's penstemon, Watson's beardtongue, Watson penstemon
* '' Penstemon wendtiorum'' B.L.TurnerTurner, B. L. (2010)
Taxonomy of the ''Penstemon campanulatus'' complex (Scrophulariaceae) and description of a new species from its midst.
''Phytoneuron'' 31 1–5.
* ''Penstemon whippleanus'' Gray – dark beardtongue, Whipple's penstemon
* '' Penstemon wilcoxii'' Rydb. – Wilcox's penstemon
* '' Penstemon wrightii'' Hook. – Wright's beardtongue
* '' Penstemon yampaensis'' Penl. – Yampa beardtongue

See also

* HMS ''Pentstemon''

References

Further reading

* Way, D. and P. James. ''The Gardener's Guide to Growing Penstemons''. David & Charles Publishers. 1998.

External links

American Penstemon Society

{{Taxonbar, from=Q809265

Medicinal plants
Plantaginaceae genera