Castilleja kaibabensis

Herbs, perennial, 1.5–3(–4) dm; from a woody caudex; with a taproot. Stems solitary or few, sometimes several, erect or ascending, unbranched, rarely branched from base or from proximal inflorescence nodes, hairs spreading or reflexed, medium length, ± stiff, distally mixed with scattered, very short stipitate-glandular ones in inflorescences. Leaves green, often with a dull red-purplish cast, linear to narrowly lanceolate or narrowly oblong, (0.8–)1.5–4 cm, not fleshy, margins plane, involute, 0(–3)-lobed, apex acuminate to acute; lobes spreading-ascending, narrowly lanceolate, apex acute. Inflorescences 2–6.5(–9) × 1.5–3.5 cm; bracts yellow, pale orange, salmon, pink, dull brick red, or reddish orange throughout, rarely red, or proximally pale greenish, distally colored as above, narrowly lanceolate to lanceolate, 0–3(–7)-lobed; lobes ascending to erect, linear to lanceolate, short to medium length, arising at or above mid length, central lobe apex obtuse, lateral ones obtuse to acute. Calyces colored as bracts, 20–27(–30) mm; abaxial and adaxial clefts 6.5–13(–18) mm, 40–60% of calyx length, deeper than laterals, lateral (2–)4–7.5(–10) mm, 25% of calyx length; lobes linear to narrowly lanceolate, apex rounded to acute. Corollas straight or slightly curved, 21–30(–35) mm; tube 13–19 mm; beak subequal to calyx or exserted, adaxially green, 8–14 mm; abaxial lip whitish to pink with deep green teeth, reduced, not exserted, sometimes visible through front calyx cleft, 0.5–2 mm, 5–15% as long as beak; teeth incurved, dark green, 0.2–1 mm. 2n = 24.

Phenology: Flowering Jul–Sep.
Habitat: Dry or exposed sites in subalpine meadows, low ridges and crests, openings in spruce-fir-aspen forests, fine silts and clay over limestone.
Elevation: 2400–2800 m.

Ariz.

Discussion

Castilleja kaibabensis is endemic to a few large meadow systems on the Kaibab Plateau, north of the North Rim of the Grand Canyon in Coconino County. Recreational activity, grazing, and road construction remain concerns for the management of this species.

Castilleja kaibabensis is in the Center for Plant Conservation’s National Collection of Endangered Plants.

Selected References

None.

Lower Taxa