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bunchleaf penstemon, foothill beardtongue, foothill penstemon

Davidson's beardtongue, Davidson's penstemon

Habit Subshrubs. Subshrubs, cespitose.
Stems

ascending to erect, 30–150 cm, glabrous or retrorsely hairy, hairs pointed, rarely glaucous.

ascending to erect, 4–10(–17) cm, retrorsely hairy or puberulent, not glaucous.

Leaves

essentially cauline, basal absent or essentially so, opposite, glabrous or retrorsely hairy to puberulent, hairs pointed, rarely glaucous;

cauline 5–11 pairs, petiolate or sessile, 10–100 × 0.5–12 mm, blade oblanceolate to lanceolate or linear, base tapered to clasping, margins entire, apex acute.

persistent, 5–10 pairs, distals usually distinctly smaller than proximals, short-petiolate or sessile, (5–)10–20(–30) × 4–11 mm, blade elliptic to orbiculate, ovate, or spatulate, base tapered, margins entire or serrulate, apex rounded to obtuse or acute, glabrous or obscurely puberulent, not glaucous.

Thyrses

interrupted or continuous, cylindric, (6–)10–32 cm, axis glabrous or retrorsely hairy, verticillasters (3–)5–14, cymes 1(–3)-flowered, (1 or)2 per node;

proximal bracts lanceolate to linear, 5–65 × 0.5–5 mm;

peduncles and pedicels ascending to erect, glabrous or retrorsely hairy.

continuous, ± secund, 1–6 cm, axis retrorsely hairy proximally, retrorsely hairy and glandular-pubescent distally, verticillasters (1 or)2–7, cymes 1-flowered;

proximal bracts round to ovate or lanceolate, 3–12 × 1–6 mm, margins entire;

peduncles and pedicels ascending to erect, glandular-pubescent, sometimes also puberulent.

Flowers

calyx lobes obovate to oblanceolate or ovate to lanceolate, 2.6–6(–7) × 1.3–3.3 mm, glabrous or puberulent;

corolla blue to violet or purple, without nectar guides, ventricose to ventricose-ampliate, 24–38 mm, glabrous externally, glabrous internally, tube 7–10 mm, throat gradually inflated, 8–11 mm diam., 2-ridged abaxially;

stamens included or longer pair reaching orifice or slightly exserted, filaments glabrous, pollen sacs parallel, 2.2–3 mm, distal 1/3–1/2 indehiscent, sides pubescent to lanate, hairs white, to 0.8 mm near filament attachment, sutures denticulate, teeth to 0.2 mm;

staminode 16–19 mm, included, 0.4–0.6 mm diam., glabrous;

style 18–27 mm.

calyx lobes lanceolate to linear, 7–12(–14) × 2.5–4.3 mm, glandular-pubescent;

corolla lavender to bluish lavender, violet, or purple, essentially unlined internally but abaxial ridges usually lavender or white, nearly personate, funnelform, 20–45 mm, glabrous externally, sparsely to moderately white-villous internally abaxially, tube (4–)6–12 mm, throat 7–12 mm diam.;

stamens included, pollen sacs 0.9–1.6 mm;

staminode 7–14 mm, slightly flattened distally, 0.1–0.2 mm diam., tip straight, distal 4–7 mm sparsely to densely villous, hairs whitish, to 1 mm;

style 19–26 mm.

Capsules

6–9 × 4–5 mm.

8–13 × 5–8 mm.

2n

= 16, 32.

Penstemon heterophyllus

Penstemon davidsonii

Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

Penstemon heterophyllus apparently occurs only in California (see discussion under 209c. var. purdyi). The species includes three varieties concentrated in the Coast Ranges from Humboldt County south to San Bernardino and San Diego counties.

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

Varieties 3 (3 in the flora).

Penstemon davidsonii occurs mostly at high elevations in the Cascade Range and Sierra Nevada.

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

Key
1. Thyrse axes glabrous; stems glabrous, rarely retrorsely hairy; calyx lobes obovate to oblanceolate, rarely lanceolate.
var. heterophyllus
1. Thyrse axes retrorsely hairy; stems retrorsely hairy; calyx lobes ovate to lanceolate.
→ 2
2. Cauline leaves 15–45 × 0.5–4 mm, axillary fascicles present, sometimes absent.
var. australis
2. Cauline leaves (25–)30–100 × 2–12 mm, axillary fascicles absent, rarely present.
var. purdyi
1. Corollas (30–)34–45 mm; leaf blades elliptic to ovate, sometimes spatulate, margins entire.
var. praeteritus
1. Corollas 20–36 mm; leaf blades spatulate to orbiculate or elliptic, margins serrulate or entire.
→ 2
2. Leaf blade margins entire, sometimes serrulate, apices rounded to obtuse.
var. davidsonii
2. Leaf blade margins ± serrulate, apices rounded to obtuse or acute.
var. menziesii
Source FNA vol. 17, p. 235. FNA vol. 17, p. 87.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Saccanthera Plantaginaceae > Penstemon > subg. Dasanthera > sect. Erianthera
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. 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. 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. heterophyllus var. australis, P. heterophyllus var. heterophyllus, P. heterophyllus var. purdyi
P. davidsonii var. davidsonii, P. davidsonii var. menziesii, P. davidsonii var. praeteritus
Synonyms P. menziesii subsp. davidsonii
Name authority Lindley: Edwards’s Bot. Reg. 22: plate 1899. (1836) — (as Pentstemon heterophyllum) Greene: Pittonia 2: 241. (1892) — (as Pentstemon)
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