Bull. Torrey Bot. Club 34: 40. 1907.
Herbs, perennial, 0.5–1(–2) dm; from a woody caudex; with a slender taproot. Stems few to several, erect or ascending, usually decumbent at base, unbranched, sometimes branched, hairs spreading, short and long, soft, mostly glandular. Leaves green to deep purple, linear to broadly lanceolate, 1–3.5(–5) cm, not fleshy, margins plane or wavy, slightly involute, (0–)3–5-lobed, apex acuminate to acute, sometimes obtuse; lateral lobes ascending-spreading, sometimes widely spreading, narrowly lanceolate to linear, mostly short, apex acute. Inflorescences 2–7 × 1.5–3 cm; bracts yellow-green, yellow, pinkish, pale reddish, or purple, sometimes distal margins pale white, oblong to broadly lanceolate to ovate, 0–5-lobed; lobes spreading, linear to narrowly lanceolate, medium length to long, usually arising above mid length, rarely from below mid length, center lobe apex rounded to truncate, lateral ones acute to obtuse. Calyces colored as bracts, sometimes strongly bicolored green or proximally whitish and distally as bract lobes, (12–)13–23(–25) mm; abaxial and adaxial clefts 5–11 mm, 45–55% of calyx length, deeper than laterals, lateral (0.5–)1–3(–5) mm, 5–20% of calyx length; lobes broadly triangular, apex obtuse to rounded, rarely acute. Corollas straight or slightly curved, 17–22(–25) mm; tube 11–16 mm; subequal to calyx or beak, sometimes abaxial lip, exserted; beak adaxially yellow to green, 4–6(–7) mm; abaxial lip green or yellow, reduced, often visible through front cleft, prominently pouched, thickened, 3–4(–5) mm, 50–67% as long as beak; teeth erect, white, yellow, pink, or purple, 1.5–3 mm. 2n = 24.
Phenology: Flowering (May–)Jun–Aug.
Habitat: Moist meadows, turf, rocky slopes and flats, talus, fellfields, subalpine to alpine.
Elevation: 1800–3500 m.
Idaho, Mont., Utah, Wyo.
Castilleja pulchella is a mostly alpine species of the mountains of western Montana and adjacent Idaho and northwestern Wyoming, as well as in the Uinta Mountains of northeastern Utah. It is similar to and likely shares ancestry with C. chrysantha of the mountains of northeastern Oregon. Castilleja pulchella is variable in color, with inflorescences ranging from pale yellow to purplish, often within the same population. Some lower elevation populations are known. These plants are considerably taller, and they tend to have only yellowish inflorescences. Where the two occur together, C. pulchella occasionally forms hybrids with C. nivea.