Penstemon humilis

Nuttall ex A. Gray

Proc. Amer. Acad. Arts 6: 69. 1862.

Common names: Low beardtongue
IllustratedEndemic
Treatment appears in FNA Volume 17. Treatment on page 208. Mentioned on page 189, 190, 192, 201, 203, 218.

Herbs. Stems decumbent to erect, (2–) 5–30 (–65) cm, retrorsely hairy, not glaucous. Leaves basal and cauline, not leathery, glabrous or retrorsely hairy; basal and proximal cauline (8–) 15–105 × 2–22 (–32) mm, blade obovate to ovate or oblanceolate, base tapered, margins entire, sometimes serrulate or serrate, apex obtuse to acute; cauline (1 or) 2–4 pairs, sessile or proximals short-petiolate, 10–35 (–45) × 1–11 mm, blade obovate to oblanceolate or lanceolate, base tapered to clasping, margins entire, rarely ± serrate, apex obtuse to acute. Thyrses interrupted, cylindric to ± secund, (1–) 3–20 (–39) cm, axis moderately glandular-pubescent, verticillasters (1–) 3–9 (–11), cymes (1 or) 2–6 (–11) -flowered, 2 per node; proximal bracts lanceolate, rarely ovate, 6–34 (–48) × 1–11 mm, margins entire; peduncles and pedicels ascending to erect, glandular-pubescent and, usually, retrorsely hairy. Flowers: calyx lobes ovate to lanceolate, 2.8–5 (–6) × 1–1.9 mm, margins entire or erose, apex acute, glandular-pubescent; corolla blue to purple or violet, with reddish violet nectar guides, bilabiate, not personate, tubular-funnelform, (7–) 8–19 mm, glandular-pubescent externally, sparsely to moderately white or yellow-lanate internally abaxially, tube 2–5 mm, throat slightly inflated, (3–) 4.5–6 mm diam., 2-ridged abaxially; stamens included, pollen-sacs opposite, navicular, 0.5–0.8 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth or papillate; staminode (3–) 7–9 mm, included, 0.1–0.3 mm diam., tip slightly recurved, distal 1–4 mm sparsely to densely pilose, hairs yellow or golden yellow, to 0.7 mm (medial hairs sparser and shorter); style 6–12 mm. Capsules 4–6 × 2.5–3.5 mm, glabrous.

Distribution

Calif., Colo., Idaho, Mont., Nev., Oreg., Utah, Wash., Wyo.

Discussion

Varieties 3 (3 in the flora).

Penstemon humilis is widespread and extremely variable throughout its range in the western United States. Except for two fairly distinct elements in Utah, most variation in the species is contained in the widespread var. humilis. D. D. Keck (1945) and N. H. Holmgren (1984) summarized the ranges and morphologic tendencies of some of the more distinctive phases.

Selected References

None.

Key

1 Cauline leaf blade margins ± serrate; basal leaves (4–)7–22(–32) mm wide; sw Utah. Penstemon humilis var. obtusifolius
1 Cauline leaf blade margins entire, rarely ± serrate distally; basal leaves 2–20 mm wide; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming. > 2
2 Basal leaves puberulent or retrorsely hairy; corollas (7–)12–19 mm; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming. Penstemon humilis var. humilis
2 Basal leaves glabrous, sometimes ± puberulent, especially along midveins and margins; corollas 10–13 mm; nc Utah. Penstemon humilis var. brevifolius

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

... more about "Penstemon humilis"
glandular-pubescent +
acute +  and obtuse +
Craig C. Freeman +
Nuttall ex A. Gray +
glandular-pubescent +
alternate +, subopposite +, whorled +  and opposite +
glaucescent +
alternate +, opposite +, whorled +, helical +  and subopposite +
cauline +, proximal +  and basal +
rarely +, not glaucous +, glabrate +, pubescent +, hairy +, glandular-lanate +, glandular-pubescent +, puberulent +, glandular +  and glabrous +
not +  and leathery +
tapered;tapered +
obovate;oblanceolate or lanceolate +
not +  and leathery +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
ovate;lanceolate +
short-tubular +  and short-campanulate +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
petiolate +  and sessile +
Low beardtongue +
not personate +  and bilabiate +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
white +, blue +  and purple or violet +
yellow-lanate +  and glandular-pubescent +
tubular-funnelform +
ampliate +
0.8 cm8 mm <br />0.008 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
2-6(-11)-flowered +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
scale-like +  and not needlelike +
Calif. +, Colo. +, Idaho +, Mont. +, Nev. +, Oreg. +, Utah +, Wash. +  and Wyo. +
drupe-like +
curved +  and straight +
1 +  and 4 +
golden yellow +  and yellow +
0 cm0 mm <br />0 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
membranous +
terminal +  and axillary +
persistent +  and deciduous +
basal +  and cauline +
hairy +  and glabrous +
not leathery +
orbiculate;linear;orbiculate;linear;truncate;oblanceolate;obovate;oblong;elliptic;round;lanceolate;ovate +
erose +  and entire +
entire +, serrate +  and serrulate +
glutinous +
glandular-ciliolate +, hairy +, puberulent +, glabrescent +, glabrous +  and glandular-pubescent +
lacerate +, toothed +  and entire +
axile +  and parietal +
basal +, apical +  and superior +
tenuinucellate +, unitegmic +  and hemitropous +
campylotropous +, hemianatropous +  and anatropous +
ascending +  and erect +
hairy +  and glandular-pubescent +
ascending;erect +
hairy +  and glandular-pubescent +
5 +  and 4 +
navicular-sigmoid +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
1/5 +  and 2/3 +
short-petiolate +
3.5 cm35 mm <br />0.035 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
3.4 cm34 mm <br />0.034 m <br /> (4.8 cm48 mm <br />0.048 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (3.4 cm34 mm <br />0.034 m <br />) +
ovate +  and lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
1 cm10 mm <br />0.01 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
Proc. Amer. Acad. Arts +
minute +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
black +, gray +, brown +  and tan +
angled +  and slightly rounded +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Illustrated +  and Endemic +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (?) +  and 0.9 cm9 mm <br />0.009 m <br /> (?) +
subalternate +, alternate +, whorled +  and opposite +
30 cm300 mm <br />0.3 m <br /> (65 cm650 mm <br />0.65 m <br />) +
glutinous +
climbing +  and scrambling +
sprawling +, creeping +  and prostrate +
decumbent;erect +
not glaucous +  and hairy +
5 cm50 mm <br />0.05 m <br /> (30 cm300 mm <br />0.3 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
papillate +  and smooth +
denticulate +
Penstemon humilis +
Penstemon sect. Penstemon +
species +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
2-ridged +  and inflated +
not constricted +
secund +  and interrupted +
20 cm200 mm <br />0.2 m <br /> (39 cm390 mm <br />0.39 m <br />) +
cylindric +
3 cm30 mm <br />0.03 m <br /> (20 cm200 mm <br />0.2 m <br />) +
straight +
gibbous +  and not spurred +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
cauline +  and proximal +