Castilleja exserta var. latifolia
Phytologia 90: 70. 2008.
Herbs 0.6–3.3 dm. Inflorescences 1.5–12 cm; bracts: distal apices pink to pale purple, sometimes white, 5–7 mm wide, 3–5(–7)-lobed; lobes linear to narrowly spatulate, less than 2 × 1–2 mm. Calyces 17.5–23 mm; abaxial clefts 4–6 mm, adaxial 9–16 mm, abaxial 40–50% of calyx length, adaxial 50–70% of calyx length, lateral 2.5–3 mm, 15% of calyx length. Corollas 20–27 mm; tube 15–20 mm; beak 5–7 mm; abaxial lip pink proximally, distal 1/3 white to yellow, becoming deep pink after anthesis, 3–5 mm.
Phenology: Flowering (Mar–)Apr–Aug.
Habitat: Coastal grasslands, dunes, sandy flats, headlands, sandy to rocky slopes.
Elevation: 0–500 m.
Discussion
Variety latifolia is a close associate of Artemisia pycnocephala along the coast of central and northern California. Sand dune populations in the vicinity of Humboldt Bay and occasionally elsewhere are unique in having almost uniformly greenish bracts, usually with white apices, and a less-inflated abaxial lip on the corollas. The inflorescences of this form also become anthcyanic very rapidly, with much of the coloration fading quickly to deep, dull reddish brown, even while flowering continues. These distinctive plants are the subject of ongoing research. The northernmost population of this form of var. latifolia occurs north of Crescent City, in northern Del Norte County, and this variety should be looked for in adjacent southwestern Oregon.
Selected References
None.