Penstemon rydbergii var. rydbergii
Stems retrorsely hairy, sometimes only in lines. Thyrses: axis retrorsely hairy or puberulent; proximal bract margins usually erose to lacerate proximally, sometimes entire. Flowers: calyx lobes (3.5–)4–6.5 × 1.6–3.5 mm, margins lacerate, rarely erose, broadly scarious, apex acuminate or short- to long-caudate; corolla 10–15 mm; pollen sacs 0.5–0.8 mm. 2n = 16.
Phenology: Flowering Jun–Aug.
Habitat: Moist, grassy meadows, moist ravines, aspen thickets, rocky hillsides, subalpine parks.
Elevation: 1900–3300 m.
Distribution
Colo., N.Mex., Utah, Wyo.
Discussion
Variety rydbergii is concentrated in the Southern Rocky Mountains from south-central Wyoming to northern New Mexico. D. D. Keck (1945) referred material from the vicinity of the Grand Canyon in Arizona and from the Uinta Mountains of northeastern Utah to var. rydbergii. Some Utah plants fit well with the concept of var. rydbergii used here; others appear to pass into Penstemon procerus. The Arizona plants are intermediate between var. aggregatus and var. rydbergii.
Selected References
None.