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lilac beardtongue, lilac penstemon, slender beardtongue, slender penstemon

Rocky Mountain beardtongue, Rocky Mountain penstemon

Habit Herbs.
Caudex

herbaceous.

Stems

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

ascending to erect, (20–)35–70(–90) cm, glabrous or ± puberulent proximally, rarely distinctly puberulent, 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.

basal and cauline, ± leathery or not, glabrous except for antrorsely-scabrous margins or ± puberulent proximally, rarely distinctly puberulent, not glaucous;

basal and proximal cauline (30–)50–150 × 5–16(–20) mm, blade oblanceolate, base tapered, margins entire, apex rounded to obtuse;

cauline 4–8 pairs, sessile, 40–100 × 2–7(–10) mm, blade lanceolate to linear, base tapered, apex acuminate.

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 to ± continuous, secund, (3–)9–40 cm, axis glabrous, verticillasters 4–10(–13), cymes 1- or 2(–4)-flowered, 2 per node;

proximal bracts lanceolate to linear, 10–65 × 1–8 mm, apex acuminate;

peduncles and pedicels glabrous, peduncles to 27 mm, pedicels 1–20 mm.

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 ovate, (2.5–)3–5 × 1.3–2.5 mm, apex acute, sometimes acuminate or obtuse, glabrous;

corolla purple to violet or blue, with violet nectar guides, ventricose-ampliate, (18–)24–32 mm, glabrous externally, glabrous internally, tube 4–7 mm, throat gradually inflated, slightly constricted at orifice, 6–10(–12) mm diam., slightly 2-ridged abaxially;

stamens: longer pair slightly exserted, pollen sacs divergent to opposite, navicular-sigmoid, 1.7–2.4 mm, dehiscing incompletely, proximal 1/4 sometimes indehiscent, connective not splitting, sides moderately to densely lanate to villous, hairs white, to 1.8 mm, sutures denticulate, teeth to 0.1 mm;

staminode 11–14 mm, included, 0.5–0.8 mm diam., tip straight, glabrous or distal 1–5 mm sparsely villous, hairs yellow or orange, to 0.7 mm;

style 17–21 mm.

Capsules

6–8 × 3–4 mm, glabrous.

7–13 × 4–7 mm.

2n

= 16.

= 16.

Penstemon gracilis

Penstemon strictus

Phenology Flowering May–Aug. Flowering Jun–Aug.
Habitat Tallgrass, mixed grass, and shortgrass prairies, foothills. Gravelly sagebrush shrublands, pinyon-juniper woodlands, oak woodlands, spruce-aspen forests.
Elevation 300–2100 m. (1000–6900 ft.) 1700–3500 m. (5600–11500 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
AZ; CA; CO; NM; UT; WY
[WildflowerSearch map]
[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.)

A disjunct population of Penstemon strictus in Mono County, California, appears to be an introduction, and collections from some counties in east-central Colorado (Arapahoe) and northeastern New Mexico (Harding and Union) also probably are due to recent introductions. Penstemon strictus is a popular ornamental; it has been seeded along some highways in Arizona, Colorado, and Wyoming.

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

Source FNA vol. 17, p. 205. FNA vol. 17, p. 180.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon Plantaginaceae > Penstemon > subg. Penstemon > sect. Glabri
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. 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
Synonyms P. gracilis subsp. wisconsinensis, P. gracilis var. wisconsinensis P. strictus subsp. angustus
Name authority Nuttall: Gen. N. Amer. Pl. 2: 52. (1818) — (as Pentstemon gracile) Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 10: 324. (1846) — (as Pentstemon)
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