Penstemon rydbergii var. oreocharis
in A. Cronquist et al., Intermount. Fl. 4: 390. 1984.
Stems glabrous, rarely ± retrorsely hairy. Thyrses: axis glabrous, rarely ± retrorsely hairy; proximal bract margins entire. Flowers: calyx lobes 3–5.5 × 1.2–2.2 mm, margins erose, sometimes lacerate, narrowly to broadly scarious, apex acute to short-caudate; corolla 10–14 mm; pollen sacs 0.5–0.7(–0.8) mm. 2n = 16.
Phenology: Flowering Jun–Aug.
Habitat: Moist grassy meadows, stream banks, montane and subalpine forests.
Elevation: 600–3100 m.
Distribution
Calif., Idaho, Nev., Oreg., Wash.
Discussion
Variety oreocharis is widespread in the mountains of the western United States, mostly from the crest of the Cascades and Sierra Nevada eastward, from north-central Washington through eastern Oregon to east-central California and west-central Nevada. D. D. Keck (1945) recognized Penstemon vaseyanus, which he distinguished from P. oreocharis (= var. oreocharis) by the former’s stouter stems, leaf margins occasionally denticulate, and corollas more funnelform and white-lanate abaxially. Many plants from the eastern flank of the Cascade Range in central Washington exhibit some or all of these features, which also are expressed among other populations of var. oreocharis.
Peck described Penstemon hesperius from plants collected in a boggy meadow in Washington County, Oregon, commenting on their tall stature and unusual habitat. D. D. Keck (1945) recognized P. hesperius, distinguishing it from P. oreocharis by its generally taller stems [50–80(–120) cm] and longer (more than 5 mm), hirtellous calyx lobes with attenuate apices. He also noted that the few specimens he had seen (from Clackamas and Washington counties, Oregon, and one from Clark or Skamania counties, Washington) came from boggy meadows. A. Cronquist (1959) synonymized P. hesperius with P. rydbergii, stating that the two species appeared to be morphologically confluent.
Plants consistent with the type of Penstemon hesperius were discovered along the Tualatin River in southeastern Washington County, Oregon, in 2008 and 2009. Preliminary assessments suggest that P. hesperius may be morphologically and genetically distinct from P. rydbergii; work to characterize P. hesperius is ongoing (G. Maffitt 2012).