Edwards’s Bot. Reg. 15: plate 1260. 1829. (as Pentstemon confertum)
Herbs. Stems ascending to erect, 4–40(–70) cm, glabrous or retrorsely hairy, not glaucous. Leaves basal and cauline, not leathery, glabrous; basal and proximal cauline 45–125 × 5–26 mm, blade elliptic to oblanceolate, base tapered, margins entire, apex obtuse to acute; cauline 4–7 pairs, sessile or proximals short-petiolate, (7–)12–86 × (2–)3–20(–25) mm, blade oblanceolate to lanceolate or elliptic, rarely ovate, base tapered to truncate, margins entire, apex obtuse to acute. Thyrses interrupted, cylindric, 2–25(–50) cm, axis glabrous or retrorsely hairy, verticillasters (1 or)2–10, cymes 2–9-flowered, 2 per node; proximal bracts lanceolate, rarely ovate, 4–50 × 2–12 mm, margins entire; peduncles and pedicels erect, retrorsely hairy. Flowers: calyx lobes oblong to lanceolate, 3–4.8 × 0.7–1.8 mm, apex truncate to cuspidate or short- to long-caudate, glabrous; corolla yellow, rarely white, ochroleucous, pink, or lavender, without nectar guides, tubular to tubular-funnelform, 6–11 mm, glabrous externally, moderately yellowish or white-lanate internally abaxially, tube 3–4 mm, throat slightly inflated, 2–3 mm diam., 2-ridged abaxially; stamens included or longer pair reaching orifice, pollen sacs opposite, explanate, 0.4–0.5 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth; staminode 4–6 mm, included, 0.3–0.4 mm diam., tip straight, distal 0.5–1 mm pilose, hairs yellowish brown, to 0.5 mm; style 7–9 mm. Capsules 3–5 × 2–3.5 mm, glabrous. 2n = 32.
Phenology: Flowering May–Aug.
Habitat: Dry meadows, grassy slopes, openings in pine forests.
Elevation: 300–2400 m.
Alta., B.C., Sask., Alaska, Idaho, Mont., Oreg., Wash.
Penstemon confertus is widespread in the Central, Northern, and Canadian Rocky mountains in southern Alberta, southern British Columbia, southwestern Saskatchewan, northern Idaho, western Montana, northeastern Oregon, and eastern Washington. Isolated populations are known in northern British Columbia (Lackman Lake) and southern Alaska (Haines). E. Heitz (1927) reported a chromosome number of 2n = ca. 16 for P. confertus; the voucher for that count has not been verified. Counts from reports by J. Clausen et al. (1940), D. D. Keck (1945), and R. Spellenberg (1971) all are 2n = 32. Putative hybrids between P. confertus and P. globosus have been documented in Idaho County, Idaho (D. V. Clark 1971).
The Thompson and Okanagan-Colville tribes of southern British Columbia and northeastern Washington use Penstemon confertus for drugs, food, and dye (D. E. Moerman 1998).