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sand dune penstemon, sand-dune beardtongue, sharp-leaf penstemon

white beardtongue, white penstemon

Stems

ascending to erect, (9–)20–60 cm, glabrous or ± scabrous, especially distally.

ascending to erect, (10–)15–50(–55) cm, retrorsely hairy proximally, glandular-pubescent distally.

Leaves

basal and cauline, glabrous, sometimes scabrous;

basal and proximal cauline (14–)30–95 × 4–15(–24) mm, blade oblanceolate to elliptic, base tapered, apex obtuse to acute or mucronate;

cauline (2 or)3–6(or 7) pairs, sessile, 18–60(–85) × (4–)8–28 mm, blade ovate to lanceolate, base tapered to cordate-clasping, apex acute to acuminate.

basal and cauline, not leathery, glabrate or puberulent to scabrous;

basal and proximal cauline petiolate, 20–85(–110) × (4–)7–18(–20) mm, blade oblanceolate or obovate to lanceolate, base tapered, margins entire to obscurely or distinctly serrate, apex obtuse to acute;

cauline 2–5(or 6) pairs, sessile or proximals short-petiolate, 25–65 × (3–)7–19(–21) mm, blade ovate to lanceolate, base tapered to clasping, margins entire or serrate to dentate, apex acute.

Thyrses

continuous or interrupted, cylindric, 6–25(–30) cm, axis glabrous, rarely scabrous or glutinous, verticillasters (5–)7–15, cymes (2–)4–8(–12)-flowered;

proximal bracts ovate to lanceolate, 14–60 × 9–30 mm, margins entire, apex obtuse to acuminate or caudate;

peduncles and pedicels glabrous or scabrous, sometimes also glutinous, peduncles to 4 mm.

continuous or interrupted, cylindric, 4–24(–30) cm, axis densely glandular-pubescent, verticillasters (2 or)3–10, cymes 2–7-flowered, 2 per node;

proximal bracts lanceolate, 17–65 × 3–17 mm;

peduncles and pedicels densely glandular-pubescent.

Flowers

calyx lobes lanceolate, (3.2–)4.5–10 × 1.2–3.2(–3.8) mm, margins entire or erose, herbaceous or narrowly scarious, glabrous or scabrous proximally and, sometimes, along margins, sometimes also glutinous;

corolla blue to violet or purple, with reddish purple nectar guides, tubular-funnelform, 11–20 mm, glabrous externally, glabrous internally, tube 5–9 mm, throat gradually inflated, 4–6 mm diam., rounded abaxially;

stamens included or longer pair reaching orifice to slightly exserted, pollen sacs opposite, navicular, 0.7–1.3(–1.5) mm, sutures papillate;

staminode 6–12 mm, reaching orifice, 0.6–1 mm diam., tip recurved, distal 1.5–3.5 mm densely pilose, hairs golden yellow, to 0.6 mm, hairs on proximal part of staminode mostly along margins;

style 8–15 mm.

calyx lobes ovate to lanceolate, 4–7 × 1.5–3 mm, glandular-pubescent;

corolla white, rarely tinged pink or lavender, with red or reddish purple nectar guides, funnelform, (12–)16–20 mm, glandular-pubescent internally, tube 4–6 mm, throat gradually inflated, not constricted at orifice, (4–)6–8 mm diam., rounded abaxially;

stamens included, pollen sacs opposite, explanate, 0.7–1.1 mm, dehiscing completely, sutures smooth;

staminode 8–9 mm, included, 0.3–0.4 mm diam., tip straight to recurved, distal 3–6 mm sparsely to moderately villous, hairs yellowish, to 1 mm;

style 9–11(–13) mm.

Capsules

7–13 × 4–7 mm.

8–12 × 4–7 mm.

2n

= 16.

Penstemon acuminatus

Penstemon albidus

Phenology Flowering Apr–Jul(–Sep).
Habitat Silty or gravelly soils, mixed-grass and shortgrass prairies.
Elevation 300–1800 m. (1000–5900 ft.)
Distribution
from FNA
ID; NV; OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
CO; IA; KS; MN; MT; ND; NE; NM; OK; SD; TX; WY; AB; MB; ON; SK
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Penstemon acuminatus includes the northern var. acuminatus, which has denser thyrses than the southern var. latebracteatus. Herbage of var. acuminatus is usually scabrous; herbage of var. latebracteatus is rarely scabrous.

The Blackfoot tribe of the Central Rocky Mountains use Penstemon acuminatus as an analgesic, antiemetic, and gastrointestinal aid (D. E. Moerman 1998).

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

Penstemon albidus is remarkably uniform throughout its range. It probably is introduced in Ontario.

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

Key
1. Styles 11–15 mm; corollas 14–20 mm; pollen sacs 0.8–1.3(–1.5) mm; calyx lobes 5–10 mm.
var. acuminatus
1. Styles 8–11 mm; corollas 11–15 mm; pollen sacs 0.7–1 mm; calyx lobes (3.2–)4.5–7 mm.
var. latebracteatus
Source FNA vol. 17, p. 113. FNA vol. 17, p. 128.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei Plantaginaceae > Penstemon > subg. Penstemon > sect. Cristati
Sibling taxa
P. abietinus, P. absarokensis, P. acaulis, 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. 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. 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. 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
Subordinate taxa
P. acuminatus var. acuminatus, P. acuminatus var. latebracteatus
Name authority Douglas ex Lindley: Edwards’s Bot. Reg. 15: plate 1285. (1829) — (as Pentstemon acuminatum) Nuttall: Gen. N. Amer. Pl. 2: 53. (1818) — (as Pentstemon albidum)
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