Castilleja pallescens var. inverta
Leafl. W. Bot. 9: 72. 1959.
Herbs 0.4–1.2 (–1.7) dm. Leaves: margins plane, 0–3 (–7) -lobed; lobes ascending-spreading. Bracts distally pale green or cream, sometimes pale yellowish or reddish purple to deep purple, lanceolate to linear-lanceolate, rigid, veins prominent, pale and contrasting with color of surfaces. Calyces purple to green with white or pink margins and veins, 15–25 (–27) mm; abaxial and adaxial clefts 7–12 mm, lateral 0.5–3 (–6) mm; lobes linear-lanceolate or narrowly triangular. Corollas subequal to calyx or beak sometimes exserted, abaxial lip sometimes partially exserted; beak adaxially whitish, buff, or pink; abaxial lip proximally green, purple, or purplish brown, distally yellow, white, or pink; teeth white, white with yellow spot proximally, cream, or pink. 2n = 24.
Phenology: Flowering May–Aug.
Habitat: Dry slopes, ridges, and plains, often with sagebrush, talus, ledges, seasonally damp meadows.
Elevation: 1500–3200 m.
Idaho, Nev., Oreg.
The range of var. inverta somewhat overlaps that of the similar Castilleja oresbia, but the two are separable by the characters of the key. The inflorescences of both species are usually pale straw yellow to pale green.
In Lemhi County, Idaho, primarily on alpine ridges along the summit of the Lemhi Range, plants apparently referable to var. inverta occur in large numbers. Almost all of them have deep reddish purple inflorescences, with a few rare variants of pale pink or pale yellow. This population system occurs on the border of the ranges of var. inverta and var. pallescens, and the entire complex deserves further study.