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lilac beardtongue, lilac penstemon, slender beardtongue, slender penstemon

Shoshone beardtongue, Tiehm's beardtongue

Habit Herbs. Herbs.
Caudex

herbaceous.

Stems

ascending to erect, (15–)20–50 cm, retrorsely hairy and glandular-pubescent, not glaucous.

ascending to erect, 6–20 cm, retrorsely hairy, hairs appressed, white, ± scalelike, not glaucous.

Leaves

basal and cauline, not leathery, glabrous or sparsely, rarely densely, puberulent;

basal and proximal cauline 25–75 × 4–15 mm, blade ovate to oblanceolate or lanceolate, base tapered, margins subentire or ± serrate, apex obtuse to acute;

cauline 4–7 pairs, sessile, 25–80(–90) × (2–)4–10(–15) mm, blade lanceolate to linear, base truncate to clasping, margins entire or serrulate to serrate, apex acute to acuminate.

cauline, opposite, retrorsely hairy, hairs white, scalelike, not glaucous;

cauline 1–4 pairs, petiolate, 15–45 × 7–24 mm, blade ovate to spatulate or lanceolate, base tapered, margins entire, apex rounded to acute.

Thyrses

interrupted, sometimes continuous, cylindric, (3–)5–17(–21) cm, axis glandular-pubescent, verticillasters (2 or)3–5(–7), cymes 2–6-flowered, 2 per node;

proximal bracts lanceolate, 5–95 × 1–12 mm, margins entire or serrulate, rarely serrate;

peduncles and pedicels ascending to erect, glandular-pubescent.

interrupted, cylindric, 2–7 cm, axis glandular-pubescent, sometimes also retrorsely hairy or appressed-hairy proximally, hairs white, scalelike, verticillasters 3 or 4(–7), cymes (1 or)2–5-flowered, 1 or 2 per node;

proximal bracts lanceolate, 9–25 × 1–5 mm;

peduncles and pedicels ascending, glandular-pubescent.

Flowers

calyx lobes ovate to lanceolate, 4–6 × 1.5–2 mm, glandular-pubescent;

corolla light lavender to lavender, with violet nectar guides, tubular, 14–22 mm, glandular-pubescent externally, moderately white-pilose internally abaxially, tube 4–6 mm, throat slightly inflated, 4–6 mm diam., prominently 2-ridged abaxially;

stamens included, pollen sacs divergent, navicular, 1–1.3 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 11–12 mm, reaching orifice, 0.4–0.5 mm diam., tip slightly recurved, distal 7–9 mm densely villous, hairs golden yellow, to 1.5 mm;

style 9–12 mm.

calyx lobes lanceolate, 4–4.8 × 1.4–2 mm, glandular-pubescent;

corolla violet to lavender, without nectar guides, abaxial ridges usually white, weakly ventricose, 15–20 mm, glandular-pubescent externally, glabrous internally, tube 4–6 mm, throat gradually inflated, 4–5 mm diam., 2-ridged abaxially;

stamens included or longer pair reaching orifice, filaments glabrous, pollen sacs nearly parallel to divergent, 1.1–1.6 mm, distal 2/3 indehiscent, sides glabrous, sutures denticulate, teeth to 0.1 mm;

staminode 8–10 mm, exserted, 0.3–0.6 mm diam., glabrous or sparsely pilose, hairs yellow, to 0.2 mm;

style 10–13 mm.

Capsules

6–8 × 3–4 mm, glabrous.

6–8 × 4–5 mm.

2n

= 16.

= 16.

Penstemon gracilis

Penstemon tiehmii

Phenology Flowering May–Aug. Flowering Jun–Aug.
Habitat Tallgrass, mixed grass, and shortgrass prairies, foothills. Sandy-loam soils, steep volcanic talus slopes.
Elevation 300–2100 m. (1000–6900 ft.) 2300–2900 m. (7500–9500 ft.)
Distribution
from FNA
CO; IA; IL; IN; MI; MN; MT; ND; NE; NM; SD; WI; WY; AB; BC; MB; ON; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
NV
[BONAP county map]
Discussion

Glabrous-leaved plants are characteristic on the prairies of most of the central and northern Great Plains, and in the foothills of the Central, Northern, and Canadian Rocky mountains. Puberulent-leaved plants from the Driftless Area of Wisconsin have been named var. wisconsinensis. Puberulent-leaved plants also occur in Alberta and in North Dakota (specimens from Barnes, Benton, Eddy, Pierce, Ramsey, Wells, and Williams counties have been seen), sometimes with glabrous-leaved plants. Penstemon gracilis is introduced in Indiana (K. Yatskievych 2000).

The roots of Penstemon gracilis are used by the Lakota of the northern Great Plains for protection from snakebites (D. E. Moerman 1998).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Penstemon tiehmii is known only from Mount Lewis in the Shoshone Range in Lander County.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 17, p. 205. FNA vol. 17, p. 244.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon Plantaginaceae > Penstemon > subg. Penstemon > sect. Saccanthera
Sibling taxa
P. abietinus, P. absarokensis, P. acaulis, P. acuminatus, P. alamosensis, P. albertinus, P. albidus, P. albomarginatus, P. ambiguus, P. ammophilus, P. anguineus, P. angustifolius, P. arenarius, P. arenicola, P. aridus, P. arkansanus, P. attenuatus, P. atwoodii, P. auriberbis, P. australis, P. azureus, P. baccharifolius, P. barbatus, P. barnebyi, P. barrettiae, P. bicolor, P. bleaklyi, P. bracteatus, P. breviculus, P. brevisepalus, P. buckleyi, P. caesius, P. caespitosus, P. calcareus, P. californicus, P. calycosus, P. canescens, P. cardinalis, P. cardwellii, P. carnosus, P. caryi, P. centranthifolius, P. cinicola, P. clevelandii, P. clutei, P. cobaea, P. comarrhenus, P. compactus, P. concinnus, P. confertus, P. confusus, P. crandallii, P. cusickii, P. cyananthus, P. cyaneus, P. cyanocaulis, P. cyathophorus, P. dasyphyllus, P. davidsonii, P. deamii, P. deaveri, P. debilis, P. degeneri, P. deustus, P. digitalis, P. diphyllus, P. discolor, P. dissectus, P. distans, P. dolius, P. duchesnensis, P. eatonii, P. elegantulus, P. ellipticus, P. eriantherus, P. euglaucus, P. fendleri, P. filiformis, P. flavescens, P. floribundus, P. floridus, P. flowersii, P. franklinii, P. fremontii, P. fruticiformis, P. fruticosus, P. gairdneri, P. gibbensii, P. glaber, P. glandulosus, P. glaucinus, P. globosus, P. goodrichii, P. gormanii, P. gracilentus, P. grahamii, P. grandiflorus, P. griffinii, P. grinnellii, P. guadalupensis, P. hallii, P. harbourii, P. harringtonii, P. havardii, P. haydenii, P. heterodoxus, P. heterophyllus, P. hirsutus, P. humilis, P. idahoensis, P. immanifestus, P. incertus, P. inflatus, P. jamesii, P. janishiae, P. kingii, P. kralii, P. labrosus, P. laetus, P. laevigatus, P. laevis, P. lanceolatus, P. laricifolius, P. laxiflorus, P. laxus, P. leiophyllus, P. lemhiensis, P. lentus, P. leonardii, P. linarioides, P. longiflorus, P. lyallii, P. marcusii, P. mensarum, P. metcalfei, P. miser, P. moffatii, P. monoensis, P. montanus, P. moriahensis, P. mucronatus, P. multiflorus, P. murrayanus, P. nanus, P. navajoa, P. neomexicanus, P. neotericus, P. newberryi, P. nitidus, P. nudiflorus, P. oklahomensis, P. oliganthus, P. ophianthus, P. osterhoutii, P. ovatus, P. pachyphyllus, P. pahutensis, P. pallidus, P. palmeri, P. papillatus, P. parryi, P. parvulus, P. parvus, P. patens, P. payettensis, P. paysoniorum, P. peckii, P. penlandii, P. pennellianus, P. perpulcher, P. personatus, P. petiolatus, P. pinifolius, P. pinorum, P. platyphyllus, P. pratensis, P. procerus, P. pruinosus, P. pseudoputus, P. pseudospectabilis, P. pudicus, P. pumilus, P. purpusii, P. putus, P. radicosus, P. rattanii, P. retrorsus, P. rhizomatosus, P. richardsonii, P. roezlii, P. rostriflorus, P. rubicundus, P. rupicola, P. rydbergii, P. saxosorum, P. scapoides, P. scariosus, P. secundiflorus, P. seorsus, P. sepalulus, P. serrulatus, P. smallii, P. spatulatus, P. speciosus, P. spectabilis, P. stenophyllus, P. stephensii, P. strictiformis, P. strictus, P. subglaber, P. subserratus, P. subulatus, P. sudans, P. superbus, P. tenuiflorus, P. tenuis, P. teucrioides, P. thompsoniae, P. thurberi, P. tidestromii, P. tiehmii, P. tracyi, P. triflorus, P. triphyllus, P. tubaeflorus, P. uintahensis, P. utahensis, P. venustus, P. virens, P. virgatus, P. wardii, P. washingtonensis, P. watsonii, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
P. abietinus, P. absarokensis, P. acaulis, P. acuminatus, P. alamosensis, P. albertinus, P. albidus, P. albomarginatus, P. ambiguus, P. ammophilus, P. anguineus, P. angustifolius, P. arenarius, P. arenicola, P. aridus, P. arkansanus, P. attenuatus, P. atwoodii, P. auriberbis, P. australis, P. azureus, P. baccharifolius, P. barbatus, P. barnebyi, P. barrettiae, P. bicolor, P. bleaklyi, P. bracteatus, P. breviculus, P. brevisepalus, P. buckleyi, P. caesius, P. caespitosus, P. calcareus, P. californicus, P. calycosus, P. canescens, P. cardinalis, P. cardwellii, P. carnosus, P. caryi, P. centranthifolius, P. cinicola, P. clevelandii, P. clutei, P. cobaea, P. comarrhenus, P. compactus, P. concinnus, P. confertus, P. confusus, P. crandallii, P. cusickii, P. cyananthus, P. cyaneus, P. cyanocaulis, P. cyathophorus, P. dasyphyllus, P. davidsonii, P. deamii, P. deaveri, P. debilis, P. degeneri, P. deustus, P. digitalis, P. diphyllus, P. discolor, P. dissectus, P. distans, P. dolius, P. duchesnensis, P. eatonii, P. elegantulus, P. ellipticus, P. eriantherus, P. euglaucus, P. fendleri, P. filiformis, P. flavescens, P. floribundus, P. floridus, P. flowersii, P. franklinii, P. fremontii, P. fruticiformis, P. fruticosus, P. gairdneri, P. gibbensii, P. glaber, P. glandulosus, P. glaucinus, P. globosus, P. goodrichii, P. gormanii, P. gracilentus, P. gracilis, P. grahamii, P. grandiflorus, P. griffinii, P. grinnellii, P. guadalupensis, P. hallii, P. harbourii, P. harringtonii, P. havardii, P. haydenii, P. heterodoxus, P. heterophyllus, P. hirsutus, P. humilis, P. idahoensis, P. immanifestus, P. incertus, P. inflatus, P. jamesii, P. janishiae, P. kingii, P. kralii, P. labrosus, P. laetus, P. laevigatus, P. laevis, P. lanceolatus, P. laricifolius, P. laxiflorus, P. laxus, P. leiophyllus, P. lemhiensis, P. lentus, P. leonardii, P. linarioides, P. longiflorus, P. lyallii, P. marcusii, P. mensarum, P. metcalfei, P. miser, P. moffatii, P. monoensis, P. montanus, P. moriahensis, P. mucronatus, P. multiflorus, P. murrayanus, P. nanus, P. navajoa, P. neomexicanus, P. neotericus, P. newberryi, P. nitidus, P. nudiflorus, P. oklahomensis, P. oliganthus, P. ophianthus, P. osterhoutii, P. ovatus, P. pachyphyllus, P. pahutensis, P. pallidus, P. palmeri, P. papillatus, P. parryi, P. parvulus, P. parvus, P. patens, P. payettensis, P. paysoniorum, P. peckii, P. penlandii, P. pennellianus, P. perpulcher, P. personatus, P. petiolatus, P. pinifolius, P. pinorum, P. platyphyllus, P. pratensis, P. procerus, P. pruinosus, P. pseudoputus, P. pseudospectabilis, P. pudicus, P. pumilus, P. purpusii, P. putus, P. radicosus, P. rattanii, P. retrorsus, P. rhizomatosus, P. richardsonii, P. roezlii, P. rostriflorus, P. rubicundus, P. rupicola, P. rydbergii, P. saxosorum, P. scapoides, P. scariosus, P. secundiflorus, P. seorsus, P. sepalulus, P. serrulatus, P. smallii, P. spatulatus, P. speciosus, P. spectabilis, P. stenophyllus, P. stephensii, P. strictiformis, P. strictus, P. subglaber, P. subserratus, P. subulatus, P. sudans, P. superbus, P. tenuiflorus, P. tenuis, P. teucrioides, P. thompsoniae, P. thurberi, P. tidestromii, P. tracyi, P. triflorus, P. triphyllus, P. tubaeflorus, P. uintahensis, P. utahensis, P. venustus, P. virens, P. virgatus, P. wardii, P. washingtonensis, P. watsonii, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Synonyms P. gracilis subsp. wisconsinensis, P. gracilis var. wisconsinensis
Name authority Nuttall: Gen. N. Amer. Pl. 2: 52. (1818) — (as Pentstemon gracile) N. H. Holmgren: Brittonia 50: 159, fig. 1F–J. (1998)
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