Oenothera hispida |
Oenothera nuttallii |
|
---|---|---|
|
Nuttall's evening primrose |
|
Habit | Herbs perennial, spreading by rhizomes (forming colonies), strigillose, often also villous; from taproot. | Herbs perennial, mostly glabrous, sometimes strigillose on leaves and/or glandular puberulent on distal parts, at least on floral tube; from a taproot, lateral roots producing adventitious shoots. |
Stems | ascending to decumbent, several-branched from base, usually also irregularly branched distally, sometimes with a single, unbranched stem, 20–60(–120) cm. |
erect, often branched, 30–100 cm. |
Leaves | in a basal rosette and cauline, 0.5–7.5(–9.5) × 0.1–2.2 cm, blade narrowly lanceolate to elliptic, margins subentire or shallowly sinuate-dentate. |
in a basal rosette and cauline, rosette weakly developed or absent, at least during flowering, 2–6(–10.5) × 0.3–0.6(–1) cm; petiole 0–2 cm; blade narrowly oblong to oblong-lanceolate, margins usually entire, sometimes remotely denticulate or repand-denticulate. |
Flowers | 4-merous, zygomorphic, opening near sunset; floral tube 4–14 mm; sepals 7–11(–14) mm; petals white, fading red, slightly unequal, elliptic, 6–10 mm, clawed; filaments 4–8.5 mm, anthers 3–6 mm, pollen 90–100% fertile; style 12–26 mm, stigma exserted beyond anthers at anthesis. |
1–several opening per day near sunset; buds nodding, weakly quadrangular, with free tips 1–2 mm; floral tube 15–40 mm; sepals 20–30 mm, not spotted; petals white, fading pink, broadly obovate or obcordate,15–30 mm; filaments 15–18 mm, anthers 8–10 mm; style 35–45 mm, stigma exserted beyond anthers at anthesis. |
Capsules | erect, pyramidal in distal 1/2, conspicuously bulging at base of distal pyramidal part, strongly 4-angled, conspicuously bulging at base, abruptly constricted to terete proximal part, 7–13 × 3–5 mm; sessile. |
erect or ascending, woody in age, straight or slightly curved, cylindrical, obtusely 4-angled, especially toward base, tapering slightly from base to apex, 20–30 × 2–3 mm; sessile. |
Seeds | (2 or)3 or 4(–8), reddish brown, 2–2.5 × 1–1.3 mm. |
numerous, in 1 row per locule, reddish dark brown, narrowly obovoid, 1.5–2.3 mm. |
2n | = 28. |
= 14, 28. |
Oenothera hispida |
Oenothera nuttallii |
|
Phenology | Flowering May–Jul(–Nov). | Flowering Jun–Sep. |
Habitat | Sandy loam. | Dry, sandy or rocky prairies, open wooded hillsides, disturbed areas, roadsides. |
Elevation | 60–1900 m. (200–6200 ft.) | 500–2200(–2900) m. (1600–7200(–9500) ft.) |
Distribution |
AR; CA; GA; TX; c Mexico |
CO; IL; MI; MN; MT; ND; NE; SD; WI; WY; AB; MB; SK
|
Discussion | Oenothera hispida is native across the eastern half of Texas, south through Mexico to Oaxaca and Puebla; it is naturalized in Sevier County, Arkansas, coastal southern California, and Glynn County Georgia. P. H. Raven and D. P. Gregory (1972[1973]) reported Oenothera hispida to be self-incompatible. It occasionally forms hybrids with O. suffrutescens. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Oenothera nuttallii had been assumed to be self-incompatible (W. L. Wagner et al. 2007), but K. E. Theiss et al. (2010) determined two plants to be self-compatible. Anogra nuttalliana Spach and Baumannia nuttalliana Spach are illegitimate names that pertain here. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 10. | FNA vol. 10. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Gaura hispida, G. crispa, G. drummondii, G. roemeriana, O. xenogaura, Schizocarya crispa, S. drummondii | O. albicaulis, O. albicaulis var. nuttallii |
Name authority | (Bentham) W. L. Wagner, Hoch & Zarucchi: PhytoKeys 50: 26. (2015) | Sweet: Hort. Brit. ed. 2, 199. (1830) |
Web links |