Epilobium ciliatum subsp. watsonii
Ann. Missouri Bot. Gard. 64: 136. 1977.
Herbs usually with leafy basal rosettes, sometimes fleshy shoots from woody caudex, often forming dense thickets. Stems 25–150(–180) cm, thick, often well branched proximally, rarely distally, subglabrous proximal to inflorescence with raised strigillose lines from margins of petioles, densely mixed strigillose and glandular puberulent distally, or densely strigillose throughout. Leaves: petiole 1–5 mm; blade ovate or broadly elliptic to lanceolate, 3.5–9.6 × 1.6–3.5 cm, apex acute or subacuminate; bracts only slightly reduced in size. Inflorescences erect racemes, congested, simple, subcorymbose. Flowers: floral tube 0.9–2.4 × 1.4–3.2 mm; sepals 3.5–7.5 × 1–2.5 mm; petals rose-purple to bright pink, 5–12(–15)× 2.3–5.5 mm; filaments pink or purple to white, those of longer stamens 2.8–7 mm, those of shorter ones 1–5.2 mm; style 2.3–7.5 mm, stigma 1.1–2.8 × 0.5–1.2 mm, sometimes exserted beyond anthers. Capsules 30–85 mm, mixed strigillose and glandular puberulent; pedicel 3–10 mm, rarely subsessile. Seeds 0.9–1.3 × 0.4–0.5 mm, chalazal collar 0.02–0.1 × 0.12–0.2 mm. 2n = 36.
Phenology: Flowering May–Oct.
Habitat: Stream banks, seepages, roadside ditches, open places along coast.
Elevation: 0–200 m.
Distribution
B.C., Calif., Oreg., Wash.
Discussion
Subspecies watsonii is a strongly maritime variant of the species that shows very consistent morphological integrity throughout its very long but narrow range along the Pacific Coast of North America from Point Conception, Santa Barbara County, California, to Vancouver Island, British Columbia. Virtually throughout its range it grows with or close to subsp. ciliatum, although the latter rarely grows in the cool maritime strip next to the coast. In areas where there is more extensive contact, such as the marshes of Sonoma County, California, the two taxa intergrade completely, from pure subsp. watsonii at Bodega Bay, to nearly pure subsp. ciliatum at Laguna de Santa Rosa.
On the Olympic Peninsula in Washington and extending north into British Columbia, subsp. watsonii intergrades not only with subsp. ciliatum, but also with subsp. glandulosum, which in the south grows at higher elevations but in the north eventually replaces subsp. watsonii along the coast into Alaska.
Selected References
None.