Syn. Fl. N. Amer. 2(1): 297. 1878.
Herbs, perennial, 0.8–2.5 dm; from a woody caudex; with slender, branching roots. Stems few-to-many, decumbent-based to erect, unbranched except for short, leafy axillary shoots, hairs sparse, spreading, medium length to long, soft and dense, short to medium length, stipitate-glandular. Leaves green or gray-green to purple (sometimes different on stems of same plant), linear-lanceolate, distal sometimes broadly lanceolate, 0.5–4 cm, not fleshy, margins plane, involute, 0 (–3) -lobed, apex acute to acuminate; lobes ascending, linear to narrowly lanceolate, apex acute to acuminate, rarely obtuse. Inflorescences 2–12 × 1–3 cm; bracts greenish to dull purplish or brownish throughout, or proximally greenish to dull purplish, distally pink to purple or magenta, rarely white, ovate, broadly lanceolate, or oblong, (0–) 3–5-lobed; lobes ascending to erect, lanceolate, medium length, arising above mid length, apex acute to rounded. Calyces proximally brown or dull magenta, sometimes green, distally colored as bracts, 12.5–18 mm; abaxial and adaxial clefts 5.5–10.5 mm, 40–65% of calyx length, deeper than laterals, lateral 0.5–2 mm, 5–15% of calyx length; lobes oblong, apex rounded. Corollas slightly curved, 16–21 mm; tube 10–16 mm; abaxial lip sometimes partly exserted, beak usually exserted; beak adaxially green, 6–7 mm, margins red; abaxial lip greenish, inflated, pouches 3, shallow, central pouch shallowly grooved, visible through front cleft, 3–4 mm, 60% as long as beak; teeth erect, violet-purple or pink, 1–2.5 mm. Stigmas greenish to deep bluish purple. 2n = 24.
Phenology: Flowering Jun–Aug.
Habitat: Moist to wet meadows and flats, shorelines, open conifer forests, subalpine and alpine, often over granite.
Elevation: 1500–3700 m.
As delimited here, Castilleja lemmonii is endemic to the highlands of the Sierra Nevada in California and in adjacent Washoe County, Nevada. It differs from C. lassenensis, a plant of volcanic highlands around Mt. Lassen, which has consistently white corollas. Corollas are usually pink to purplish in C. lemmonii. Castilleja lemmonii also tends to have somewhat shorter lateral calyx clefts, though the two species overlap slightly in this character.
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