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sawsepal penstemon, southern smooth beardtongue, western smooth beardtongue

trumpet penstemon, tube beardtongue, white wand beardtongue

Habit Herbs.
Stems

ascending, (10–)50–65(–80) cm, glabrous or puberulent to pubescent, not glaucous.

erect, 25–85(–100) cm, glabrous, not glaucous.

Leaves

basal and cauline, or basal absent or reduced, not leathery, glabrous or puberulent to pubescent, not glaucous;

basal and proximal cauline 20–80(–155) × 5–20(–45) mm, blade obovate to oblanceolate or lanceolate, base tapered, margins entire, usually undulate, apex obtuse to acute, sometimes mucronate;

cauline (2 or)3–6(–8) pairs, sessile, 27–120(–150) × (6–)22–35(–43) mm, blade lanceolate, base truncate to cordate, apex obtuse to acute.

basal and cauline, basal often withering by anthesis, not leathery, glabrous;

basal and proximal cauline 25–110 × 6–38 mm, blade spatulate to ovate, base tapered, margins entire or ± serrate, apex rounded to obtuse;

cauline 5–8(–10) pairs, sessile, 15–100(–135) × 4–20(–38) mm, blade ovate to lanceolate, base tapered to clasping, margins entire or ± serrate, apex acute to acuminate.

Thyrses

continuous, secund, (3–)6–26(–30) cm, axis glabrous or puberulent, verticillasters (3–)5–12, cymes 2–4-flowered, 2 per node;

proximal bracts ovate to lanceolate, 14–100 × 2–36 mm;

peduncles and pedicels glabrous or puberulent, peduncles to 71 mm, pedicels 4–14 mm.

interrupted, cylindric, 8–30(–40) cm, axis glandular-pubescent, verticillasters 4–8(–12), cymes 3–9-flowered, 2 per node;

proximal bracts ovate to lanceolate, 9–50 × 2–10 mm, margins entire or ± serrulate;

peduncles and pedicels ascending to erect, glabrous or glandular-pubescent.

Flowers

calyx lobes ovate to orbiculate, 2–11 × 1.3–5.5 mm, glabrous or puberulent;

corolla blue to violet, with reddish purple nectar guides, ventricose, 24–48 mm, glabrous externally, glabrous internally or sparsely to moderately white-lanate internally abaxially, tube 5–12 mm, throat gradually inflated, slightly constricted at orifice, 8–13(–18) mm diam., rounded abaxially;

stamens included or longer pair reaching orifice, pollen sacs divergent, navicular, 1.4–2.5(–2.8) mm, dehiscing incompletely, connective not splitting, sides sparsely to moderately hirsute, hairs white or tan, to 0.5 mm, rarely glabrous, sutures denticulate, teeth to 0.2 mm;

staminode (15–)18–22 mm, included or barely exserted, 0.6–1.3 mm diam., tip straight to recurved, rounded to distinctly bifurcate at apex, glabrous or distal 1–2 mm sparsely lanate, hairs pale yellow, to 1.5 mm;

style 18–20 mm.

calyx lobes ovate, 2.5–5 × 1.5–2.5 mm, glandular-pubescent;

corolla white, without nectar guides, funnelform, 15–22 mm, glandular-pubescent externally, glandular-pubescent internally, tube slightly differentiated, 5–7 mm, throat slightly inflated, 4–6 mm diam., rounded abaxially;

stamens included or longer pair reaching orifice, pollen sacs divergent, explanate, 0.8–1 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth;

staminode 9–11 mm, included or reaching orifice, 0.2–0.3 mm diam., tip recurved, distal 3–4 mm sparsely villous, hairs yellowish or brownish yellow, to 0.8 mm;

style 10–12 mm.

Capsules

10–17 × 5–8 mm.

7–10 × 3–5 mm, glabrous.

2n

= 32.

Penstemon glaber

Penstemon tubaeflorus

Phenology Flowering May–Jul.
Habitat Tallgrass prairies, woodlands, roadsides.
Elevation 20–600 m. (100–2000 ft.)
Distribution
from FNA
CO; MT; ND; NE; NM; SD; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; CT; IA; IL; IN; KS; KY; LA; MA; ME; MO; MS; NE; NH; NY; OH; PA; RI; TN; TX; VT; WI; ON
[WildflowerSearch map]
Discussion

Varieties 3 (3 in the flora).

The Penstemon glaber complex has been treated with as many as four species (F. W. Pennell 1920b) or one variable species as treated herein. M. K. W. Latady (1985) found clinal variation in most morphologic characters used to distinguish taxa in the complex and recognized only one species and two varieties: var. glaber (including var. alpinus) in the plains and mountains from southeastern Montana south to central Colorado; and var. brandegeei, in the mountains from central Colorado south to north-central New Mexico. A case for recognizing var. alpinus, as is done here, can be made on morphological, phenological, and ecological grounds.

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

Penstemon tubaeflorus is concentrated in the southeastern Great Plains and Ozark Highlands, where it probably is native. Penstemon tubaeflorus appears to have naturalized eastward and northward in North America due to habitat disturbance and planting. Sometimes it grows in mixed populations with P. digitalis. Fruiting specimens of P. tubaeflorus often are misidentified as P. digitalis; the former can be distinguished by its more cylindric inflorescences with erect peduncles and smaller capsules.

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

Key
1. Calyx lobes 2–4.8 mm, apices rounded or abruptly short-acuminate; staminode apices rounded.
var. glaber
1. Calyx lobes 3.8–11 mm, apices long-acuminate; staminode apices rounded or bifurcate.
→ 2
2. Staminode apices rounded or bifurcate; corollas 24–35 mm; stems glabrous or puberulent proximally.
var. alpinus
2. Staminode apices usually bifurcate; corollas 27–48 mm; stems puberulent to pubescent proximally.
var. brandegeei
Source FNA vol. 17, p. 167. FNA vol. 17, p. 225.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Glabri Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon
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. 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. tenuiflorus, P. tenuis, P. teucrioides, P. thompsoniae, P. thurberi, P. tidestromii, P. tiehmii, P. tracyi, P. triflorus, P. triphyllus, 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. glaber var. alpinus, P. glaber var. brandegeei, P. glaber var. glaber
Synonyms P. tubaeflorus var. achoreus
Name authority Pursh: Fl. Amer. Sept. 2: 738. (1813) — (as Pentstemon glabra) Nuttall: Trans. Amer. Philos. Soc., n. s. 5: 181. (1835) — (as Pentstemon tubaeflorum)
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