Penstemon albidus
Gen. N. Amer. Pl. 2: 53. 1818. (as Pentstemon albidum)
Stems ascending to erect, (10–)15–50(–55) cm, retrorsely hairy proximally, glandular-pubescent distally. Leaves basal and cauline, not leathery, glabrate or puberulent to scabrous; basal and proximal cauline petiolate, 20–85(–110) × (4–)7–18(–20) mm, blade oblanceolate or obovate to lanceolate, base tapered, margins entire to obscurely or distinctly serrate, apex obtuse to acute; cauline 2–5(or 6) pairs, sessile or proximals short-petiolate, 25–65 × (3–)7–19(–21) mm, blade ovate to lanceolate, base tapered to clasping, margins entire or serrate to dentate, apex acute. Thyrses continuous or interrupted, cylindric, 4–24(–30) cm, axis densely glandular-pubescent, verticillasters (2 or)3–10, cymes 2–7-flowered, 2 per node; proximal bracts lanceolate, 17–65 × 3–17 mm; peduncles and pedicels densely glandular-pubescent. Flowers: calyx lobes ovate to lanceolate, 4–7 × 1.5–3 mm, glandular-pubescent; corolla white, rarely tinged pink or lavender, with red or reddish purple nectar guides, funnelform, (12–)16–20 mm, glandular-pubescent internally, tube 4–6 mm, throat gradually inflated, not constricted at orifice, (4–)6–8 mm diam., rounded abaxially; stamens included, pollen sacs opposite, explanate, 0.7–1.1 mm, dehiscing completely, sutures smooth; staminode 8–9 mm, included, 0.3–0.4 mm diam., tip straight to recurved, distal 3–6 mm sparsely to moderately villous, hairs yellowish, to 1 mm; style 9–11(–13) mm. Capsules 8–12 × 4–7 mm. 2n = 16.
Phenology: Flowering Apr–Jul(–Sep).
Habitat: Silty or gravelly soils, mixed-grass and shortgrass prairies.
Elevation: 300–1800 m.
Distribution
Alta., Man., Ont., Sask., Colo., Iowa, Kans., Minn., Mont., Nebr., N.Mex., N.Dak., Okla., S.Dak., Tex., Wyo.
Discussion
Penstemon albidus is remarkably uniform throughout its range. It probably is introduced in Ontario.
Selected References
None.