Duration: Annual
Nativity: Native
Lifeform: Forb/Herb
General: Annual herb, 30-150 cm tall, from short slender taproot; stems solitary to few per plant, erect, usually unbranched; herbage covered with stipitate glands (stalked glands) and sometimes also nonglandular hairs.
Leaves: Alternate and sessile along the stems; blades linear to lanceolate, 4-10 cm long and 2-5 mm wide near the base, soft-textured, with entire margins.
Flowers: Red and showy, in terminal spikes 10-40 cm long; flowers are dense near the top of the spike, and toward the bottom of the spike the flowers more widely spaced; each flower is subtended by a showy floral bract, 2-5 cm long, longer than the flower, green with a red tip, entire, and glandular-pubescent; calyx of four united sepals about 15 mm long, cleft on both sides for about one-half the length of the tube, green, glandular-pubescent, with triangular lobes; petals about the same length as the sepals, fused into a slender tube and strongly 2-lipped at the top, the upper lip long and yellow, and lower lip 1-2 mm long with strongly back-curved red-violet teeth.
Fruits: Capsules narrowly ovoid; splitting open longitudinally to release many tiny seeds.
Ecology: Found in moist soils from 4,500-7,500 ft (1372-2286 m); flowers June-August.
Distribution: AZ and NM; south to n MEX
Notes: An annual Indian paintbrush with narrow leaves, glandular herbage, and a red inflorescence. The red component to the inflorescnce is not the flowers themselves but the bracts that subtend each flower; the lower two-thirds or so of each bract is green, and the tips are red. The sepals are green and the corolla (fused petals) just peeks out from the sepals and is 2-lipped, with the upper lip appearing beaklike and yellow, and the lower lip shorter, toothed, and reddish. This species is somewhat common in central and southern Arizona and New Mexico, especially at the middle elevations. Similar to C. exilis, another annual paintbrush which is common farther north, in the Great Basin Desert and on the Colorado Plateau. C. exilis has slightly wider leaves and floral bracts, and thoroughly yellow corollas. Some authorities fully subsume C. exilis into C. minor and do not even consider them to be separate varieties.
Ethnobotany: Roots used to make a dye.
Etymology: Castilleja is named for Spanish botanist Domingo Castillejo (1744-1793); minor means lesser, referring to the slender stems.
Synonyms: None
Editor: SBuckley 2010, AHazelton 2017
