MISSOURI EVENING PRIMROSE
File Size: 94 KB
 
Oenothera macrocarpa  Nutt.  subsp. macrocarpa 
Tallgrass Prairie National Preserve, Chase County, Kansas
Perennial
Height: 6-18 inches
Family: Onagraceae - Evening Primrose Family
Flowering Period:   May, June, July
Stems: Decumbent to ascending, few to many, sometimes branched, frequently reddish, appressed-hairy.
Leaves: Alternate, simple, stalked or uppermost sessile, numerous, oblanceolate to elliptic-lanceolate, 2 to 6 inches long, .25 to 1.5 inches wide, thick, leathery, green, young leaves and buds grayish, appressed-hairy; margins entire or shallowly toothed; tips pointed or rounded; mature buds usually erect.
Inflorescences: Solitary flowers, in leaf axils.
Flowers: Showy, 3 to 6 inches wide, floral tubes 2 to 6 inches long; sepals 4, linear-lanceolate to lanceolate, bending abruptly downward and toward 1 side, often purple-spotted; petals 4, 1 to 2 inches long, nearly as wide, yellow, fading reddish or orange; stamens 8, filaments nearly as long as petals; stigma deeply 4-lobed, cross-shaped.
Fruits: Capsules, 1.5 to 4 inches long, conspicuously 4-winged; seeds numerous, small, angular, corky.
Habitat: Dry rocky prairies, limestone hillsides, road-cuts, and disturbed areas.
Distribution: East 3/4 of Kansas.
Comments: The flowers open near sunset and close by mid-morning of the following day. Night-flying moths pollinate the flowers, which face upward at first, and then turn downward after pollination. Missouri evening primrose is drought-resistant. Three other subspecies of Oenothera macrocarpa occur in Kansas.

Missouri evening primrose leaves
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Tallgrass Prairie National Preserve, Chase County, Kansas
Missouri evening primrose flower
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Tallgrass Prairie National Preserve, Chase County, Kansas
Missouri evening primrose
147 KB
Russell County, Kansas
Missouri evening primrose
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Russell County, Kansas
Missouri evening primrose sepals
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Konza Prairie, Riley County, Kansas
Missouri evening primrose
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Geary County, Kansas
Missouri evening primrose
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Geary County, Kansas