Weed of the Week: Cutleaf Evening-primrose
Written by: Garret Montgomery, Jason Bond, and Tom Eubank
Cutleaf Evening-primrose
Family: Onagraceae
Scientific Name: Oenothera laciniata Hill
Synonyms: Evening primrose, primrose, sundrops
Cutleaf evening-primrose seedling
Cutleaf evening-primrose is a herbaceous winter annual or biennial dicot plant with extremely wide variation in growth habits and leaf shapes. Cotyledons are kidney-shaped and have petioles. Leaves initially develop as a basal rosette, are variable in shape, can be coarsely toothed or irregularly lobed along the margin, and have hairs on tops of leaf blades and no hairs underneath. Stems are hairy and usually red in color and can range from very simple to highly branched. Flowers are yellow or red. Key identifying characteristics of the species are the distinctive white mid-vein found on most leaves and a reddish base when cut with a sharp knife near the soil line.
Cutleaf evening-primrose is native to the United States and can be found across most of the eastern parts of the country. It is common in agronomic fields, pastures, roadsides, gardens, and waste sites in Mississippi. Cutleaf evening-primrose can be a severe problem for spring burndown, especially in fields where all tillage is completed in the fall. Glyphosate is generally ineffective when applied alone. Tank mixtures of 2,4-D or dicamba with glyphosate applied in early-spring should adequately control cutleaf evening-primrose prior to planting. Although it is not toxic, this weed is most problematic in pastures because its texture makes it unsuitable for forage and it also lowers hay quality.
Bryson, C.T. and M.S. DeFelice. 2009. Weeds of the South. Athens, GA: University of Georgia Press. pp. 250.
Virginia Tech Weed Identification Guide. http://www.ppws.vt.edu/scott/weed_id/oeola.htm
Photo: Virginia Tech Weed ID Guide
Irregular leaf shapes of young cutleaf evening-primrose
I am trying to identify the most unusual pale yellow cutleaf evening primrose that has come up every year in my wildflower field for the last five years in Brookshire, Texas. Guests sit around in chairs enthralled to watch the flower buds pop open in the blink of an eye at exactly 8:00 in the evening in late April to mid May. Do all evening primroses behave that way? It is spectacular to witness.
Its leaf most resembles the oenothera grandis drawing in A Field Guide to Southwestern and Texas Wildflowers. The flower can reach 5 cm. Thanks for any info you can give me. Janeen
Not all evening-primrose species flower at sunset. This phenomenon is an identifying characteristic of common evening-primrose (Oenothera biennis). Showy evening-primrose (Oenothera speciosa) produces white flowers that open in the evening in the northern portions of its range (Oklahoma, Kansas, Missouri, etc.); however, in the southern portions of its range along the Gulf, it produces pink flowers that open in the morning. The flowers of cutleaf evening-primrose (Oenothera laciniata) open in the evening and wither by morning.
Cutleaf Evening Primrose is an annual, biennial or shorted lived perennial weed.