Oenothera triloba

Oenothera triloba
Conservation status
Apparently Secure  (NatureServe) [1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Myrtales
Family:	Onagraceae
Genus:	Oenothera
Species:	O. triloba
Binomial name
Oenothera triloba Nutt.
Synonyms [2]
Lavauxia nuttalliana Lavauxia triloba Lavauxia watsonii Oenothera rhizocarpa Oenothera roemeriana

Oenothera triloba, with common names stemless evening primrose and sessile evening primrose ^[3] is a flowering plant in the primrose family. It is native to North America, where it is primarily found in northern Mexico and in the south-central United States. ^[4] It is found in dry, open areas such as glades, prairies, and sometimes even lawns. It appears to respond positively to soil disturbance. ^{[5] [6]}

It is a winter annual that produces large yellow flowers in the spring. The flowers open near sunset. ^[5]

Taxonomy

Oenothera triloba was scientifically described and named by Thomas Nuttall in 1821. It is classified in the genus Oenothera as part of the family Onagraceae. According to Plants of the World Online it has no accepted varieties, but it has 8 synonyms including five species and three varieties. ^[2]

Table of Synonyms

Name	Year	Rank	Notes
Lavauxia nuttallianaSpach	1835	species	= het.
Lavauxia triloba(Nutt.) Bartl.	1837	species	≡ hom.
Lavauxia triloba var. watsoniiBritton	1894	variety	= het.
Lavauxia watsoniiSmall	1903	species	= het.
Oenothera rhizocarpaSpreng.	1825	species	= het.
Oenothera roemerianaScheele	1849	species	= het.
Oenothera triloba var. parvifloraS.Watson	1877	variety	= het.
Oenothera triloba var. watsonii(Britton) F.C.Gates	1939	variety	= het.
Notes: ≡ homotypic synonym  ; = heterotypic synonym

Uses

Among the Zuni people, the plant is used as an ingredient of "schumaakwe cakes" and used externally for rheumatism and swelling. ^[7] They also grind the roots and use them as food. ^[8]

References

1. NatureServe (5 September 2025). "Oenothera triloba". NatureServe Explorer. Arlington, Virginia. Retrieved 19 September 2025.
2. "Oenothera triloba Nutt". Plants of the World Online . Royal Botanic Gardens, Kew . Retrieved 19 September 2025.
3. USDA GRIN Taxonomy , retrieved 15 June 2016
4. Kartesz, John T. (2014). "Oenothera triloba". County-level distribution map from the North American Plant Atlas (NAPA). Biota of North America Program (BONAP). Retrieved 17 January 2017.
5. Shinners and Mahler's Illustrated Flora of North Central Texas Online
6. "Flora of the Southern and Mid-Atlantic States".
7. Matilda Coxe Stevenson (1915). Ethnobotany of the Zuni Indians. SI-BAE Annual Report #30. p. 55.
8. Albert B. Reagan (1929). "Plants used by the White Mountain Apache Indians of Arizona". Wisconsin Archeologist . 8: 143–161.