Penstemon hallii

Stems ascending to erect, (7–) 9–16 (–25) cm, glabrous or ± glandular-pubescent distally, not glaucous. Leaves basal and cauline, or basal absent or reduced, ± leathery, glabrous except for antrorsely-scabrous margins, not glaucous; basal and proximal cauline 16–85 × 3–9 mm, blade spatulate to lanceolate, base tapered, margins entire, apex rounded to obtuse or acute; cauline 2–4 pairs, sessile, 24–55 × 2–5 mm, blade lanceolate, proximals sometimes spatulate, base truncate, apex obtuse to acute. Thyrses continuous, cylindric to secund, (1–) 2–7 cm, axis glandular-pubescent, verticillasters 1–7, cymes 1–4-flowered, 2 per node; proximal bracts lanceolate, rarely oblanceolate, 9–26 × 1–3 mm; peduncles and pedicels ascending to erect, glandular-pubescent. Flowers: calyx lobes obovate to elliptic, (4–) 5–6.5 × 3–4 mm, margins erose or lacerate, glandular-pubescent, sometimes only proximally; corolla blue to violet or purple, with reddish purple nectar guides, ventricose, 14–25 mm, glabrous externally, glabrous or sparsely white-lanate internally abaxially, tube 2–3 mm, throat abruptly inflated, not constricted at orifice, 6–7 mm diam., rounded abaxially; stamens included, pollen-sacs opposite, navicular to subexplanate, 1.2–1.4 mm, dehiscing completely, sides glabrous, rarely sparsely pilose, hairs white, to 0.8 mm near connective, sutures smooth or obscurely papillate; staminode 10–15 mm, included or reaching orifice, 0.6–1 mm diam., tip straight, distal 3–6 mm moderately to densely pubescent, hairs golden yellow, to 0.6 mm (hairs scattered proximally); style 10–13 mm. Capsules 6–9 × 4–7 mm.

Phenology: Flowering Jul–Aug.
Habitat: Rocky to gravelly alpine meadows.
Elevation: 2800–4000 m.

Colo.

Discussion

Penstemon hallii is known from alpine zones on the highest peaks in Colorado.

Selected References

None.

Lower Taxa