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Palmer's beardtongue, Palmer's penstemon, scented beardtongue, scented penstemon

foxglove beard-tongue, penstémon digitale, tall white beardtongue, talus slope penstemon

Habit Herbs. Herbs.
Stems

ascending to erect, 43–140 cm, glaucous.

erect, 25–90 cm, glabrous or sparsely retrorsely hairy, slightly glaucous or not.

Leaves

basal and proximal cauline (28–)52–120(–145) × (5–)25–50(–60) mm, blade ovate, base tapered, margins coarsely dentate, apex obtuse to acute;

cauline 5–8 pairs, sessile or connate-perfoliate, 25–130 × 7–45 mm, blade ovate to triangular, base of distals auriculate-clasping or connate-perfoliate, margins coarsely dentate, distals sometimes entire, apex acute.

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

basal and proximal cauline 30–180(–250) × 4–38(–70) mm, blade spatulate to obovate or lanceolate, base tapered, margins entire or ± serrate or denticulate, apex rounded to obtuse or acute;

cauline 5–8 pairs, petiolate or sessile, 26–195 × 4–55 mm, blade ovate to lanceolate, base tapered to clasping, margins entire or denticulate, apex acuminate to acute.

Thyrses

interrupted, rarely continuous, secund, 7–63 cm, axis glabrous or glandular-pubescent, verticillasters (4–)7–17, cymes (1 or)2–5-flowered;

proximal bracts ovate to lanceolate, 8–40 × 4–38 mm;

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

interrupted, conic, 7–26(–34) cm, axis glabrous proximally, sparsely to densely glandular-pubescent distally, verticillasters (2 or)3–6, cymes (3–)5–12(–18)-flowered, 2 per node;

proximal bracts lanceolate to linear, 9–105 × 1–40 mm, margins entire, sometimes serrulate;

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

Flowers

calyx lobes ovate, (3.4–)4.2–6(–7.5) × 1.9–3.6 mm, glabrous or glandular-pubescent;

corolla pale pink to white or pinkish lavender, with reddish purple nectar guides, strongly bilabiate, ventricose-ampliate, 25–38 mm, glandular-pubescent externally, glandular-pubescent internally, sometimes also sparsely white-lanate abaxially, tube 4–8 mm, length 1–1.4 times calyx lobes, throat abruptly inflated, constricted at orifice, 12–21 mm diam., rounded abaxially;

stamens included or longer pair reaching orifice, filaments of shorter pair glandular-puberulent proximally, pollen sacs navicular, 1.6–2.4 mm, sutures smooth;

staminode 25–30 mm, exserted, 0.9–1.1 mm diam., tip strongly recurved to coiled, distal 8–10 mm, and especially tip, moderately to densely lanate, hairs yellow, to 3.5 mm, proximal 6–8 mm glandular-puberulent;

style 19–23 mm, glabrous or sparsely glandular-pubescent proximally.

calyx lobes ovate, sometimes lanceolate, 4–8 × 2–3 mm, apex acute to acuminate, glandular-pubescent;

corolla white, sometimes tinged lavender, with reddish purple nectar guides, ventricose, (17–)20–30 mm, glandular-pubescent externally, sparsely to moderately white-pubescent internally abaxially, tube 6–9 mm, throat abruptly inflated, 8–12 mm diam., slightly 2-ridged abaxially;

stamens included or longer pair reaching orifice, pollen sacs opposite, navicular, 1.4–1.7 mm, dehiscing completely, connective splitting, sides sparsely pubescent, hairs white or purplish, to 0.6 mm, rarely glabrous, sutures papillate;

staminode 13–17 mm, reaching orifice, 0.3–0.4 mm diam., tip straight to slightly recurved, distal 6–8 mm sparsely to moderately villous, hairs yellowish, to 1.5(–2) mm;

style 13–18 mm.

Capsules

11–16 × 6–8 mm, sparsely glandular-pubescent distally.

8–14 × 4–6 mm, glabrous.

2n

= 96.

Penstemon palmeri

Penstemon digitalis

Phenology Flowering Apr–Jul.
Habitat Prairies, meadows, roadsides, clearings in woods.
Elevation 10–500 m. (0–1600 ft.)
Distribution
from FNA
AZ; CA; CO; ID; NM; NV; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DC; DE; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; NB; NS; ON; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

Penstemon ×bryantiae D. D. Keck, a hybrid between P. palmeri and P. spectabilis, was described based on plants that volunteered in the Rancho Santa Ana Botanic Garden in 1935 (D. D. Keck 1937b). Penstemon ×mirus A. Nelson, a putative hybrid between P. eatonii and P. palmeri, has been reported from Arizona (A. Nelson 1938).

A poultice prepared from Penstemon palmeri is applied to snakebites by the Kayenta Navajo of northeastern Arizona (D. E. Moerman 1998).

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

Penstemon digitalis appears to be native in the central Mississippi River Basin, with human activities expanding its range, particularly eastward (F. W. Pennell 1935). It is listed in VASCAN as introduced in the four Canadian provinces where it occurs (http://data.canadensys.net/vascan/taxon/7273).

Plants resembling Penstemon digitalis but with smaller corollas (17–23 mm versus 23–30 mm), less glandular-pubescent inflorescences, less scarious-margined calyx lobes, and stems sometimes puberulent (versus glabrous) have been named P. alluviorum. Plants with those features come mostly from the southeastern Central Lowlands and north-central Coastal Plain provinces in the eastern United States in the south-central part of the range of P. digitalis (Alabama, Arkansas, Illinois, Indiana, Kentucky, Mississippi, Missouri, Ohio, and Tennessee). A. C. Koelling (1964) observed overlap in characters used to distinguish P. alluviorum from P. digitalis and concluded it was a small-flowered variant of P. digitalis.

Specimens of Penstemon digitalis with lanceolate and acuminate-tipped calyx lobes can be mistaken for P. calycosus, but calyx lobe length and, usually, the presence of hairs on the pollen sacs allow them to be accurately identified.

Penstemon digitalis is widely cultivated and spreads readily. R. R. Clinebell and P. Bernhardt (1998) found evidence that plants are self-compatible.

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

Key
1. Corolla tubes 7–8 mm; distal cauline leaves sessile, sometimes connate-perfoliate.
var. macranthus
1. Corolla tubes 4–6 mm; distal cauline leaves connate-perfoliate.
→ 2
2. Peduncles, pedicels, and calyx lobes glandular-pubescent; pollen sacs 1.8–2.4 mm.
var. palmeri
2. Peduncles, pedicels, and calyx lobes glabrous; pollen sacs 1.6–2(–2.2) mm.
var. eglandulosus
Source FNA vol. 17, p. 252. FNA vol. 17, p. 202.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Spectabiles 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. 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. 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. 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. palmeri var. eglandulosus, P. palmeri var. macranthus, P. palmeri var. palmeri
Synonyms P. alluviorum
Name authority A. Gray: Proc. Amer. Acad. Arts 7: 379. (1868) — (as Pentstemon) Nuttall ex Sims: Bot. Mag. 52: plate 2587. (1825) — (as Pentstemon)
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