Oenothera capillifolia subsp. capillifolia
Herbs annual or short-lived perennial.Stems 1–several, unbranched or sparsely branched, ascending to erect, 30–80 cm. Leaves 2.5–9 × 0.2–1 cm; blade margins remotely serrulate to spinulose-serrate. Flowers: buds with free tips 0.5–4 mm; sepals with conspicuously keeled midribs. 2n = 14.
Phenology: Flowering Mar–Sep.
Habitat: Prairies, open places in oak savannas on rocky, clay, or sandy soil, often calcareous.
Elevation: 0–900 m.
Distribution
La., Okla., Tex.
Discussion
Subspecies capillifolia occurs from Blaine and Lincoln counties, Oklahoma, south through a narrow portion of north-central Texas to central Texas, where it is widely distributed, especially on the Edwards Plateau; also occurring locally in western and southern Louisiana. The floral tubes and/or stigma of some populations, especially from Bexar, Blanco, Comal, Gillespie, Hays, Kendall, Kerr, and Travis counties, Texas, are a deep blackish purple, while others are yellow, which is typical of the section.
Selected References
None.