Bot. Beechey Voy., 154. 1833.
Herbs, annual, sometimes biennial, 0.6–3.5 dm; with fibrous roots. Stems few to many, sometimes solitary (var. meadii), ascending or erect, often decumbent proximally, unbranched or branched above base, hairs sparse to moderately dense, spreading, long, soft, eglandular, mixed with short stipitate-glandular hairs. Leaves green or brownish in upland forms, linear-lanceolate to widely lanceolate, linear, elliptic, obovate, or oblong, rarely ovate or cup-shaped, (0.6–)0.8–5 cm, fleshy or not, margins plane, flat, 3–5(–7)-lobed, apex rounded to obtuse or acuminate, abaxial surface often stipitate-glandular, adaxial sometimes shiny, glabrous; lobes ascending to erect, linear to lanceolate, apex acute or obtuse. Inflorescences 1.5–9(–13) × 1–4 cm; bracts proximally green, rarely brownish purple, distally white, cream, pink, or purple on apices, lanceolate, oblong, or ovate, (0–)3–5(–7)-lobed; lobes ascending or divaricate-ascending, oblong to linear, short to long, arising below or above mid length, central lobe apex usually rounded to truncate, others acute to obtuse. Calyces green to pale yellowish green or tipped with white or purple, 8–23 mm; abaxial and adaxial clefts 5–9 mm, 33–50(–67)% of calyx length, lateral 2–5.5 mm, 20–40% of calyx length; lobes linear or narrowly lanceolate to oblong or ± triangular, apex acuminate or narrowly acute to obtuse or rounded. Corollas straight, 14–24 mm; tube 11–21 mm, expanded distally; abaxial lip and beak usually exserted, beak straight or slightly curved, adaxially white, yellow, or pink, sometimes green or purplish, (1–)4–7 mm, sparsely to densely short-hairy; abaxial lip pale to bright yellow, sometimes becoming pink, orange, or red after anthesis, with red-brown or purple spots at base of each tooth and sometimes at base of each pouch, conspicuous, pouches 3, ± prominent, divergent, saccate, 2–7 × 3–7 mm, (33–)60–75(–90)% as long as beak; teeth erect, sometimes spreading, white, pink, purple, or green, often with whitish bases, 1–3 mm. Filaments glabrous. 2n = 24.
B.C., Calif., Oreg., Wash.
Varieties 4 (4 in the flora).
Castilleja ambigua is a complex species, treated here with four varieties, though many localized variations exist among populations, and these are still incompletely understood.
|1||Bract lobes linear; stems erect; moist inland meadows and vernal pools on volcanic substrates; c Napa County, California.||Castilleja ambigua var. meadii|
|1||Bract lobes linear to oblong; stems ± decumbent, at least proximally; coastal salt marshes, margins of brackish estuaries, coastal sandy bluffs, mesic to ± xeric inland grasslands; British Columbia to California.||> 2|
|2||Bracts pink to purple distally; stems unbranched or few-branched from mid stem; salt marshes; Humboldt Bay region, nw California.||Castilleja ambigua var. humboldtiensis|
|2||Bracts white distally, rarely pink or cream; stems often branched from base; salt marshes, sandy coastal bluffs, inland grasslands; British Columbia to California.||> 3|
|3||Corolla beaks usually white or yellow, abaxial lips yellow; salt marshes, sandy coastal bluffs, inland grasslands; s British Columbia to c California.||Castilleja ambigua var. ambigua|
|3||Corolla beaks usually pink to purplish, abaxial lips yellow, becoming white and then red or soft pink-purple; grassy coastal bluffs and adjacent sand dunes; vicinity of Monterey Bay, California.||Castilleja ambigua var. insalutata|