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glandular penstemon, sticky-stem beardtongue, sticky-stem penstemon

trumpet penstemon, tube beardtongue, white wand beardtongue

Habit Herbs. Herbs.
Stems

ascending to erect, (30–)40–100 cm, viscid glandular-pubescent, not glaucous.

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

Leaves

basal and cauline, opposite, viscid glandular-pubescent, not glaucous;

basal and proximal cauline 25–120(–260) × 7–20(–65) mm, blade elliptic to lanceolate, base tapered, margins entire, subentire, or irregularly serrate to dentate, apex acute to acuminate;

cauline 4–10 pairs, sessile, 32–80(–120) × 12–45 mm, blade ovate to obovate, elliptic, or lanceolate, base tapered to cordate-clasping, margins entire or subentire to irregularly serrate to dentate, apex obtuse to acute or acuminate.

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

interrupted, cylindric, (5–)8–31 cm, axis viscid glandular-pubescent, verticillasters 3–7, cymes (1 or)2–8-flowered, 2 per node;

proximal bracts ovate, 18–60 × 11–44 mm;

peduncles and pedicels ascending to erect, viscid glandular-pubescent.

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 lanceolate, 9–15 × 2.3–3.8 mm, viscid glandular-pubescent;

corolla lavender to bluish lavender or purple, with dark violet nectar guides, ampliate, (28–)30–40 mm, glandular-pubescent externally, sparsely to moderately white-pubescent internally abaxially, tube 9–11 mm, throat gradually inflated, 12–15 mm diam., rounded abaxially;

stamens included, filaments glabrous, pollen sacs parallel, 1.6–2.2 mm, distal 1/2 indehiscent, sides glabrous, sutures denticulate, teeth to 0.2 mm;

staminode 22–26 mm, exserted, 0.8–1 mm diam., glabrous, rarely distal 2–4 mm sparsely pubescent, hairs yellow, to 0.4 mm;

style 20–26 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

9–13 × 5–6.5 mm.

7–10 × 3–5 mm, glabrous.

2n

= 32.

Penstemon glandulosus

Penstemon tubaeflorus

Phenology Flowering May–Jul.
Habitat Tallgrass prairies, woodlands, roadsides.
Elevation 20–600 m. (100–2000 ft.)
Distribution
from FNA
ID; OR; WA
[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 2 (2 in the flora).

Two allopatric varieties of Penstemon glandulosus have been distinguished based on basal leaf morphology. Leaf margins occasionally vary from entire to serrate or dentate among individuals in some populations, but the general pattern of leaf variation does appear to be geographically correlated.

(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. Basal leaves: blade margins irregularly serrate to dentate.
var. glandulosus
1. Basal leaves: blade margins entire or subentire.
var. chelanensis
Source FNA vol. 17, p. 233. FNA vol. 17, p. 225.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Saccanthera 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. glaber, 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. glandulosus var. chelanensis, P. glandulosus var. glandulosus
Synonyms P. tubaeflorus var. achoreus
Name authority Douglas ex Lindley: Edwards’s Bot. Reg. 15: plate 1262. (1829) — (as Pentstemon glandulosum) Nuttall: Trans. Amer. Philos. Soc., n. s. 5: 181. (1835) — (as Pentstemon tubaeflorum)
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