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blue-stem beardtongue, bluestem penstemon

Watson's beardtongue, Watson's penstemon

Habit Herbs.
Stems

ascending to erect, (16–)20–60 cm, glabrous or ± puberulent proximally, ± glaucous.

ascending to erect, 25–60 cm, glabrous or sparsely puberulent, not glaucous.

Leaves

basal and cauline, ± leathery or not, glabrous or proximals puberulent proximally or along midveins, ± glaucous;

basal and proximal cauline (30–)50–95 × 10–15(–28) mm, blade spatulate to oblanceolate, base tapered, margins entire, usually undulate, apex rounded to obtuse;

cauline 2–4 pairs, sessile, 20–73 × 4–15 mm, blade lanceolate to elliptic, base truncate to clasping, margins crisped or undulate, apex acute.

essentially cauline, basal absent or poorly developed, not leathery, glabrous or puberulent;

cauline 4–8 pairs, short-petiolate or sessile, 30–70(–80) × 8–18(–35) mm, blade oblanceolate to lanceolate, base tapered or clasping, margins entire, apex obtuse to acute.

Thyrses

interrupted, secund to subsecund, (4–)8–31 cm, axis glabrous, verticillasters 5–9(–12), cymes (1 or)2–5-flowered, 2 per node;

proximal bracts ovate to lanceolate, 15–50 × 3–23 mm;

peduncles and pedicels glabrous, peduncles to 18 mm, pedicels 1–7 mm.

continuous or interrupted, cylindric, (1.5–)5–16 cm, axis ± retrorsely hairy, verticillasters 2–6(–10), cymes (2–)6–14-flowered, 2 per node;

proximal bracts lanceolate to linear, rarely ovate, 3–60 × 1–23 mm, margins entire;

peduncles and pedicels ascending to erect, ± retrorsely hairy.

Flowers

calyx lobes ovate, 3.5–4.5 × 1.4–2 mm, apex acute to acuminate, glabrous;

corolla blue to violet, with violet nectar guides, funnelform to weakly ventricose, 14–18(–20) mm, glabrous or ± glandular externally, glabrous internally, tube 5–8 mm, throat gradually inflated, not constricted at orifice, 5–7 mm diam., rounded abaxially;

stamens: longer pair reaching orifice, pollen sacs divergent, navicular-sigmoid, 1.2–1.7 mm, dehiscing incompletely, proximal 1/4 indehiscent, connective not splitting, sides sparsely to moderately pilose, hairs white, to 0.5(–0.7) mm, sutures denticulate, teeth to 0.1 mm;

staminode: 9–11 mm, reaching orifice, 0.2–0.4 mm diam., tip straight, distal 2–6 mm sparsely pilose, hairs golden yellow, to 0.6 mm;

style 9–12 mm.

calyx lobes broadly ovate, 1.8–3(–3.5) × 1.4–2 mm, apex obtuse to acute or short-cuspidate, glabrous;

corolla blue to violet or purple, with faint reddish purple nectar guides, funnelform, 12–16(–18) mm, glabrous externally, sparsely white-villous internally abaxially, tube 4–5 mm, throat gradually inflated, 3–6 mm diam., 2-ridged abaxially;

stamens included or longer pair slightly exserted, pollen sacs opposite, navicular, 0.9–1 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 8–9 mm, reaching orifice, 0.2–0.3 mm diam., tip slightly recurved, distal 3–4 mm moderately to densely villous, hairs golden yellow, to 1 mm;

style 9–13 mm.

Capsules

6–10 × 4–5 mm.

4–7 × 3.5–5 mm, glabrous.

2n

= 16.

Penstemon cyanocaulis

Penstemon watsonii

Phenology Flowering Apr–Jun. Flowering May–Aug.
Habitat Rocky slopes, pinyon-juniper, oak, and oak-juniper woodlands. Dry, rocky slopes, sagebrush shrublands, pine-oak and pine woodlands.
Elevation 1300–2700 m. (4300–8900 ft.) 1700–3200 m. (5600–10500 ft.)
Distribution
from FNA
CO; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; ID; NV; UT; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon cyanocaulis is known from Mesa, Montrose, and San Miguel counties, Colorado, and Carbon, Emery, Grand, and San Juan counties, Utah. It has crisped or undulate leaf margins that help distinguish it in the field.

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

Penstemon watsonii is known from mountain ranges throughout the Intermountain Region. Penstemon laxus, which has been included as a variety of this species, has corollas 2–3 mm in diameter and densely white-villous internally abaxially, and is known from south-central Idaho north of the Snake River. Penstemon watsonii does enter extreme south-central Idaho but is not known to occur north of the Snake River.

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

Source FNA vol. 17, p. 165. FNA vol. 17, p. 226.
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. 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
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. tubaeflorus, P. uintahensis, P. utahensis, P. venustus, P. virens, P. virgatus, P. wardii, P. washingtonensis, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Name authority Payson: Bot. Gaz. 60: 380. (1915) — (as Pentstemon) A. Gray: in A. Gray et al., Syn. Fl. N. Amer. 2(1): 267. (1878) — (as Pentstemon watsoni)
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