Burke: Oenothera curtiflora vs. Oenothera elata

	Oenothera curtiflora	Oenothera elata
	small-flowered gaura, velvet weed, velvetweed	Hooker's evening primrose
Habit	Annual from a taproot, the stem single, simple below and branched above, 0.2-2 m. tall, puberulent, but also with soft, spreading hairs 2 mm. long.
Leaves	Leaves alternate, the basal leaves spatulate, the lower cauline leaves oblong, the others oblong-lanceolate to lanceolate, 4-15 cm. long, entire to wavy-dentate, gradually reduced upward to very small, linear floral bracts.
Flowers	Inflorescence of many-flowered spikes, 1-3 dm. long; calyx tube very slender, 2-3 mm. long, with 4 distinct, reflexed lobes 2-3 mm. long; petals 4, short-clawed, pinkish, 2 mm. long; stamens 8, filaments without basal scales; ovary inferior, 4-celled.
Fruits	Fruit hardened, 6-10 mm. long, spindle-shaped, glabrous, 4-angled by not winged.

	Oenothera curtiflora	Oenothera elata
Flowering time	June-September	June-September
Habitat	Meadows, stream banks, roadsides, sandy or rocky slopes, often where disturbed.	Sagebrush hills to mid elevations in the mountains, generally where moist.
Distribution	Occurring east of the Cascades crest in Washington; south-central Washington to eastern Oregon, Nevada, and Arizona, east to North Dakota,, Iowa, and Louisiana; introduced in California and the eastern U.S., South America, Asia, and Australia. [WildflowerSearch map] [BONAP county map]	Occurring chiefly east of the Cascades crest in Washington; Washington to California, east to the Rocky Mountains and southern Great Plains in the U.S. [WildflowerSearch map] [BONAP county map]
Origin	Introduced from the central U.S.	Native
Conservation status	Not of concern	Not of concern
Sibling taxa	O. biennis, O. cespitosa, O. elata, O. flava, O. glazioviana, O. pallida, O. suffrutescens	O. biennis, O. cespitosa, O. curtiflora, O. flava, O. glazioviana, O. pallida, O. suffrutescens
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Oenothera elata

small-flowered gaura, velvet weed, velvetweed

Hooker's evening primrose

Habit

Annual from a taproot, the stem single, simple below and branched above, 0.2-2 m. tall, puberulent, but also with soft, spreading hairs 2 mm. long.

Leaves

Leaves alternate, the basal leaves spatulate, the lower cauline leaves oblong, the others oblong-lanceolate to lanceolate, 4-15 cm. long, entire to wavy-dentate, gradually reduced upward to very small, linear floral bracts.

Flowers

Inflorescence of many-flowered spikes, 1-3 dm. long;

calyx tube very slender, 2-3 mm. long, with 4 distinct, reflexed lobes 2-3 mm. long;

petals 4, short-clawed, pinkish, 2 mm. long;

stamens 8, filaments without basal scales;

ovary inferior, 4-celled.

Fruits

Fruit hardened, 6-10 mm. long, spindle-shaped, glabrous, 4-angled by not winged.

Oenothera curtiflora

Oenothera elata

Flowering time

June-September

Habitat

Meadows, stream banks, roadsides, sandy or rocky slopes, often where disturbed.

Sagebrush hills to mid elevations in the mountains, generally where moist.

Distribution

Occurring east of the Cascades crest in Washington; south-central Washington to eastern Oregon, Nevada, and Arizona, east to North Dakota,, Iowa, and Louisiana; introduced in California and the eastern U.S., South America, Asia, and Australia.

[WildflowerSearch map]

[BONAP county map]

Occurring chiefly east of the Cascades crest in Washington; Washington to California, east to the Rocky Mountains and southern Great Plains in the U.S.

[WildflowerSearch map]

[BONAP county map]

Origin

Introduced from the central U.S.

Native

Conservation status

Not of concern

Sibling taxa