Penstemon

Taxobox
name = Beard-tongue


image_width = 250px
image_caption = Balloon Flower ("Penstemon palmeri")
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
ordo = Lamiales
familia = Plantaginaceae
genus = "Penstemon"
genus_authority = Mitch.
subdivision_ranks = Species
subdivision =See text.

"Penstemon" (Beard-tongue) is a large genus of North American and East Asian plants traditionally placed in the Scrophulariaceae family. Due to new genetic research it has now been placed 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 herbaceous perennials, the remainder being shrubs or subshrubs. Heights can range from 10 cm to as much as 3 meters.

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

Native Americans long used penstemon roots to relieve toothache. 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 travelled 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 was formed to promote both horticultural and botanical interest.

Horticulture

Although penstemons are among the most attractive native flowers of North America, Europe has always been far more active in their cultivation, and hundreds of hybrids have been developed there since the early 1800s. 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 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. cobaeus" and "P. hartwegii".

In North America, penstemon species 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 penstemon species in North America is found at The Arboretum at Flagstaff, which hosts a [http://www.thearb.org/penstemon_festival.htm Penstemon Festival] each summer.

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
*"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 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. "praeteritus" Steens Mountain 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
*"Penstemon diphyllus" Rydb. twoleaf beardtongue
*"Penstemon discolor" Keck Cataiina beardtongue
*"Penstemon dissectus" Ell. dissected beardtongue
*"Penstemon distans" N. Holmgren Mt. Tumbull beardtongue
*"Penstemon dolius" M.E. Jones ex Pennell Jone's penstemon , Jones' beardtongue
*"Penstemon dubius" A. Davids. (pro sp.) dubius penstemon
*"Penstemon eatonii" Gray Eaton penstemon , Eaton's 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 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. Chilean 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 tubiflorus" 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 whippleanus" Gray dark beardtongue, Whipple's penstemon
*"Penstemon wilcoxii" Rydb. Wilcox's penstemon
*"Penstemon wrightii" Hook. Wright's beardtongue
*"Penstemon yampaensis" Penl. Yampa beardtongue

References

* David Way & Peter James, "The Gardener's Guide to Growing Penstemons" (David & Charles Publishers, 1998) ISBN 0-7153-0550-6

External links