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white beardtongue, white penstemon

eastern white-flower beardtongue

Habit Herbs.
Stems

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

ascending to erect, 20–80 cm, retrorsely hairy and ± glandular-lanate, retrorse hairs sometimes few or distal only, not glaucous.

Leaves

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.

basal and cauline, not leathery, moderately to densely glandular-lanate, especially along major veins abaxially;

basal and proximal cauline 40–138 × 7–37 mm, blade spatulate to oblanceolate or elliptic, base tapered, margins entire or ± serrate to dentate, apex rounded to obtuse or acute;

cauline 4–7 pairs, sessile or proximals sometimes petiolate, (11–)20–110 × 3–30(–40) mm, blade ovate to lanceolate, base truncate to clasping, sometimes tapered, margins entire or crenate-serrate to dentate, apex acute to acuminate.

Thyrses

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.

interrupted, conic, (3–)8–37 cm, axis moderately to densely glandular-pubescent to glandular-lanate, verticillasters 3–6(or 7), cymes 3–10(–13)-flowered, 2 per node;

proximal bracts lanceolate, 6–40 × 1–10 mm, margins entire or ± serrate;

peduncles and pedicels ascending, moderately to densely glandular-pubescent to glandular lanate.

Flowers

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.

calyx lobes ovate to broadly lanceolate, 2–5 × 1.3–2 mm, glandular-pubescent;

corolla white, without nectar guides, personate, tubular, 21–28 mm, sparsely glandular-pubescent externally, moderately to densely white-villous internally abaxially, tube 6–8 mm, throat slightly inflated, 5–8 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular to subexplanate, 1–1.2 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 13–16 mm, exserted, 0.4–0.6 mm diam., tip straight, distal 10–12 mm moderately to densely pubescent, hairs yellow, to 1.6 mm;

style 16–19 mm.

Capsules

8–12 × 4–7 mm.

5–7 × 3–5 mm, glabrous.

2n

= 16.

Penstemon albidus

Penstemon tenuiflorus

Phenology Flowering Apr–Jul(–Sep). Flowering Apr–Jun.
Habitat Silty or gravelly soils, mixed-grass and shortgrass prairies. Dry woods, cedar glades, prairies, barrens, cliffs.
Elevation 300–1800 m. (1000–5900 ft.) 30–80 m. (100–300 ft.)
Distribution
from FNA
CO; IA; KS; MN; MT; ND; NE; NM; OK; SD; TX; WY; AB; MB; ON; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; KY; MS; TN
[WildflowerSearch map]
[BONAP county map]
Discussion

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

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

Penstemon tenuiflorus is concentrated in the Interior Low Plateaus region of western Kentucky, central Tennessee, and northwestern Alabama, and in the Black Belt subsection of the Coastal Plain of central Alabama and northeastern Mississippi.

R. K. Clements et al. (1998) observed that the leaves of Penstemon tenuiflorus bear both simple and stellate hairs, reporting only simple hairs on the leaves of closely related P. hirsutus. However, stellate hairs occur in the leaf axils of plants in some populations of P. hirsutus, and they are common on the stems. Stellate hairs also occur on other diploid, tubular-flowered eastern North American species, including P. arkansanus, P. australis, P. brevisepalus, P. canescens, P. laxiflorus, P. oklahomensis, and P. pallidus. Stellate hairs have not been observed on any of the polyploid, ventricose-flowered eastern North American species.

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

Source FNA vol. 17, p. 128. FNA vol. 17, p. 223.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Cristati Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon
Sibling taxa
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
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. 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
Name authority Nuttall: Gen. N. Amer. Pl. 2: 53. (1818) — (as Pentstemon albidum) Pennell: Addisonia 4: 79, plate 160. (1919)
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