Fl. N.W. Amer., 510. 1901.
Subshrubs, cespitose. Stems ascending to erect, 3–16 cm, puberulent to pubescent, not glaucous. Leaves persistent, 3–8 pairs, distals usually distinctly smaller than proximals, short-petiolate or sessile, 4–22 × 3–14 mm, blade round to elliptic or spatulate, base tapered to cuneate, margins ± serrate, apex rounded to obtuse, rarely acute, glabrous or hairy, usually glaucous. Thyrses continuous, ± secund, 1–3 cm, axis hairy proximally, pubescent or glandular-pubescent distally, verticillasters 1–3, cymes 1-flowered; proximal bracts elliptic to ovate, 3–9 × 2–6 mm; peduncles and pedicels ascending to erect, glandular-pubescent. Flowers: calyx lobes lanceolate-elliptic to oblong, 6–11 × 2–2.8 mm, glandular-pubescent; corolla pink to red, pinkish lavender, or rose red, essentially unlined internally but abaxial ridges usually white, not personate, funnelform, 25–36 mm, glabrous externally, glabrous internally or sparsely white-lanate abaxially, tube 8–12 mm, throat 6–8 mm diam.; stamens: longer pair exserted, pollen-sacs 1–1.5 mm; staminode 13–15 mm, slightly flattened distally, 0.1 mm diam., tip straight, glabrous or distal 1–2 mm sparsely villous, hairs yellow, to 0.8 mm; style 26–30 mm. Capsules 7–9 × 5–7 mm. 2n = 16.
Phenology: Flowering Jun–Jul.
Habitat: Cliffs, rock outcrops.
Elevation: 60–2400 m.
Calif., Oreg., Wash.
Penstemon rupicola occurs largely in the Siskiyou Mountains and Cascade Range from northern California to northern Washington. It is partly sympatric with and forms hybrids with P. cardwellii, P. davidsonii var. davidsonii, and P. fruticosus var. fruticosus (A. D. Every 1977). Hybrids between P. rupicola and P. davidsonii var. davidsonii are encountered frequently in the vicinity of Crater Lake National Park and Mt. Hood (Every).
"/3-3/4timescorollathroat" is not declared as a valid unit of measurement for this property.