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

Canaan Mountain beardtongue, sandloving penstemon

Habit Herbs.
Stems

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

decumbent to ascending, 5–26 cm, usually ± fistulose, glutinous and covered with sand, not glaucous.

Leaves

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.

basal and cauline, not leathery, glutinous and covered with sand, not glaucous;

basal and proximal cauline 18–80 × 4–15 mm, blade oblanceolate, base tapered, margins entire, crisped, apex obtuse to acute;

cauline 2–5 pairs, sessile, 15–75 × 2–8 mm, blade oblanceolate to lanceolate, base tapered to truncate, margins crisped, apex rounded or obtuse to acute.

Thyrses

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.

continuous, cylindric, 4–15 cm, axis glutinous and covered with sand, verticillasters 4–10, cymes 1–6-flowered, 2 per node;

proximal bracts lanceolate, 14–45 × 2–5(–8) mm;

peduncles and pedicels glutinous and covered with sand.

Flowers

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.

calyx lobes lanceolate, 5–6.5 × 1–2 mm, glutinous and covered with sand;

corolla lavender to blue-lavender, with violet nectar guides, weakly ventricose, 14–17 mm, glabrous externally, usually glutinous and covered with sand distally, especially on lobes, glabrous internally, tube 5–6 mm, throat gradually inflated, not constricted at orifice, 5–6 mm diam., slightly 2-ridged abaxially;

stamens: longer pair reaching orifice, pollen sacs opposite, navicular, 0.9–1.4 mm, dehiscing completely or incompletely, connective splitting or not, sides glabrous, sutures papillate;

staminode: 8–9 mm, included, 0.3–0.5 mm diam., tip straight, distal 4–5 mm sparsely papillate, papillae violet, to 0.2 mm;

style 10–12 mm.

Capsules

8–14 × 4–6 mm, glabrous.

3.5–6.5 mm.

2n

= 96.

Penstemon digitalis

Penstemon ammophilus

Phenology Flowering Apr–Jul. Flowering May–Jun.
Habitat Prairies, meadows, roadsides, clearings in woods. Sand dunes, ponderosa pine forests, mixed shrublands.
Elevation 10–500 m. (0–1600 ft.) 1800–2200 m. (5900–7200 ft.)
Distribution
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]
from FNA
UT
[BONAP county map]
Discussion

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.)

Penstemon ammophilus is known from Garfield, Kane, and Washington counties. Populations occur on aeolian sand, derived from the Navajo Sandstone. The fistulose stems of P. ammophilus are unique in Penstemon.

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

Source FNA vol. 17, p. 202. FNA vol. 17, p. 161.
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. 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. 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
Synonyms P. alluviorum
Name authority Nuttall ex Sims: Bot. Mag. 52: plate 2587. (1825) — (as Pentstemon) N. H. Holmgren & L. M. Shultz: Brittonia 34: 381, fig. 1. (1982)
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