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eastern white beardtongue, pale beardtongue, pale penstemon

Platte River penstemon, Wasatch beardtongue, Wasatch penstemon

Habit Herbs.
Stems

ascending to erect, 25–55(–65) cm, retrorsely hairy and glandular-villous proximally, retrorsely hairy and glandular-pubescent distally, glandular hairs sometimes sparse, not glaucous.

decumbent to erect, 5–70(–90) cm, glabrous or sparsely to densely puberulent, not glaucous.

Leaves

basal and cauline, basal often withering by anthesis, not leathery, sparsely to densely pubescent, sometimes also with scattered glandular hairs, abaxially, sparsely pubescent adaxially;

basal and proximal cauline 20–120(–180) × 5–35(–40) mm, blade spatulate to obovate or ovate, base tapered, margins subentire or ± serrate or dentate, apex rounded to obtuse or acute;

cauline 4–8 pairs, sessile, 22–100 × 4–24 mm, blade ovate to lanceolate, base truncate to clasping, margins subentire or ± serrate or dentate, apex acute to acuminate.

basal and cauline, ± leathery or not, glabrous or basal ones sparsely to densely puberulent, not glaucous;

basal and proximal cauline (20–)45–160 × 3–40(–55) mm, blade obovate to oblanceolate, base tapered, margins entire, apex obtuse to acute;

cauline 1–6 pairs, sessile or proximals short- to long-petiolate, 16–100 × 5–45(–60) mm, blade ovate or oblanceolate to lanceolate, base cordate-clasping to clasping, apex obtuse to acute.

Thyrses

interrupted, conic, 5–26(–30) cm, axis sparsely to densely glandular-pubescent, verticillasters 3–8, cymes 2–8(–16)-flowered, 2 per node;

proximal bracts lanceolate, 7–72 × 2–22 mm, margins entire or ± dentate;

peduncles and pedicels ascending, sparsely to densely glandular-pubescent.

continuous or interrupted, cylindric to subsecund, 2–30 cm, axis glabrous, verticillasters 2–12, cymes 3–7-flowered, 2 per node;

proximal bracts ovate to lanceolate, 7–80 × (1–)3–35 mm;

peduncles and pedicels glabrous, peduncles to 20 mm, pedicels 1–9 mm.

Flowers

calyx lobes ovate to lanceolate, (2–)3–5 × 1–3 mm, sparsely glandular-pubescent;

corolla white, sometimes tinged lavender or blue, with reddish purple nectar guides, tubular to tubular-funnelform, 16–22 mm, glandular-pubescent externally, moderately whitish or yellowish lanate internally abaxially, tube 4–6 mm, throat slightly inflated, 4–7 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, (0.8–)1–1.2 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 10–12 mm, exserted, 0.2–0.3 mm diam., tip straight to slightly recurved, distal 8–9 mm moderately to densely villous, hairs yellow or golden yellow, to 1.5 mm;

style 12–14 mm.

calyx lobes ovate to lanceolate, 3–6.5 × 1.3–2.6 mm, apex acute to acuminate or cuspidate, glabrous;

corolla blue to violet, without nectar guides, ventricose, 12–25(–28) mm, glabrous externally, glabrous internally, tube 6–11 mm, throat gradually inflated, not constricted at orifice, 6–11 mm diam., 2-ridged abaxially;

stamens included or longer pair reaching orifice, pollen sacs divergent, navicular, 1.2–2(–2.2) mm, dehiscing incompletely, proximal 1/4–1/3 indehiscent, connective not splitting, sides hispid, hairs white, to 0.5 mm, sutures denticulate, teeth to 0.1 mm;

staminode 11–14 mm, included or reaching orifice, 0.3–0.6 mm diam., tip straight to recurved, distal 6–9 mm sparsely to moderately pilose to lanate, hairs orange, yellow, or white, to 1 mm;

style 9–16 mm.

Capsules

5–7 × 3–5 mm, glabrous.

7–15 × 5–10 mm.

2n

= 16.

Penstemon pallidus

Penstemon cyananthus

Phenology Flowering Apr–Jun(–Jul).
Habitat Tallgrass prairie, limestone and sandstone glades, barrens, rocky oak-hickory woodlands.
Elevation 10–300 m. (0–1000 ft.)
Distribution
from FNA
AL; AR; CT; DC; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; ON
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; MT; UT; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon pallidus is concentrated in the Central Lowlands and Ozark Plateau of the central United States. F. W. Pennell (1935) believed it to be native there, having spread eastward as a result of human activities, as in Ontario.

Penstemon brevisepalus, which has been synonymized with P. pallidus by many authors, is treated here as a distinct species. Characters distinguishing the species are discussed under 147. P. brevisepalus.

Some specimens from north-central Arkansas and north-central Missouri are morphologically intermediate between Penstemon pallidus and P. arkansanus.

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

Varieties 3 (3 in the flora).

Penstemon compactus and P. longiflorus have been treated as elements of the P. cyananthus complex (F. W. Pennell 1920b; D. D. Keck 1940b). All of these taxa occur from the Wasatch Range northward into the Central Rocky Mountains.

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

Key
1. Cauline leaf blades lanceolate to oblanceolate; calyx lobes ovate to lanceolate, apices acute to cuspidate, rarely acuminate.
var. subglaber
1. Cauline leaf blades ovate to lanceolate; calyx lobes lanceolate, rarely ovate, apices acuminate, rarely acute.
→ 2
2. Verticillasters 4–12; thyrses 4–30 cm; stems ascending to erect, 20–70(–90) cm; corollas 16–25(–28) mm.
var. cyananthus
2. Verticillasters 2 or 3; thyrses 2–6 cm; stems decumbent to ascending, 5–25(–32) cm; corollas 12–16(–20) mm.
var. judyae
Source FNA vol. 17, p. 214. FNA vol. 17, p. 163.
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. 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. 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. 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. cyananthus var. cyananthus, P. cyananthus var. judyae, P. cyananthus var. subglaber
Name authority Small: Fl. S.E. U.S., 1060, 1337. (1903) — (as Pentstemon) Hooker: Bot. Mag. 75: plate 4464. (1849) — (as Pentstemon)
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