Penstemon davidsonii

Greene

Pittonia 2: 241. 1892.

Common names: Davidson’s beardtongue
Endemic
Synonyms: Penstemon menziesii subsp. davidsonii (Greene) Piper
Treatment appears in FNA Volume 17. Treatment on page 87. Mentioned on page 86.

Subshrubs, cespitose. Stems ascending to erect, 4–10 (–17) cm, retrorsely hairy or puberulent, not glaucous. Leaves 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 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 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 8–13 × 5–8 mm.

Distribution

B.C., Calif., Nev., Oreg., Wash.

Discussion

Varieties 3 (3 in the flora).

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

Selected References

None.

Key

1 Corollas (30–)34–45 mm; leaf blades elliptic to ovate, sometimes spatulate, margins entire. Penstemon davidsonii 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. Penstemon davidsonii var. davidsonii
2 Leaf blade margins ± serrulate, apices rounded to obtuse or acute. Penstemon davidsonii var. menziesii

"/3-3/4timescorollathroat" is not declared as a valid unit of measurement for this property.

... more about "Penstemon davidsonii"
white +  and lavender +
white-villous +  and glabrous +
2 cm20 mm <br />0.02 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
not glaucous +, puberulent +  and glabrous +
Craig C. Freeman +
Greene +
glandular-pubescent +  and hairy +
alternate +, opposite +, whorled +, helical +  and subopposite +
tapered +
Dasanthera +
elliptic;orbiculate ovate or spatulate +
not +  and leathery +
1.2 cm12 mm <br />0.012 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
glandular-pubescent +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.43 cm4.3 mm <br />0.0043 m <br />) +
short-tubular +  and short-campanulate +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
sessile +, short-petiolate +  and petiolate +
Davidson’s beardtongue +
not +, personate +  and bilabiate +
purple +, violet +  and lavender to bluish lavender +
glabrous +, hairy +  and glandular-pubescent +
ventricose-ampliate +  and ampliate +
sessile +  and short-petiolate +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
scale-like +  and not needlelike +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
usually distinctly smaller +
0.4 cm4 mm <br />0.004 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
B.C. +, Calif. +, Nev. +, Oreg. +  and Wash. +
drupe-like +
curved +  and straight +
1 +  and 4 +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
membranous +
terminal +  and axillary +
subopposite +  and opposite +
persistent +
not +, glaucous +, hairy +  and glabrous +
5 (?) +  and 10 (?) +
leathery +
orbiculate;linear;orbiculate;linear;truncate;oblanceolate;obovate;oblong;elliptic;round;lanceolate;ovate +
erose +  and entire +
entire +  and serrulate +
glandular +, glabrous +  and glandular-pubescent +
toothed +  and entire +
axile +  and parietal +
basal +, apical +  and superior +
tenuinucellate +, unitegmic +  and hemitropous +
campylotropous +, hemianatropous +  and anatropous +
ascending +  and erect +
puberulent +  and glandular-pubescent +
puberulent +  and glandular-pubescent +
5 +  and 4 +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
round +  and ovate or lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
minute +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (?) +  and 1.4 cm14 mm <br />0.014 m <br /> (?) +
subalternate +, alternate +, whorled +  and opposite +
climbing +  and scrambling +
sprawling +, creeping +  and prostrate +
ascending;erect +
4 cm40 mm <br />0.04 m <br /> (10 cm100 mm <br />0.1 m <br />) +
1.9 cm19 mm <br />0.019 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
Penstemon menziesii subsp. davidsonii +
Penstemon davidsonii +
Penstemon sect. Erianthera +
species +
0.7 cm7 mm <br />0.007 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
2-ridged +  and inflated +
not constricted +
secund +  and continuous +
conic +  and cylindric +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
straight +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
gibbous +  and not spurred +
0.6 cm6 mm <br />0.006 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
subshrub +  and cespitose +