SERRATE-LEAF EVENING PRIMROSE
File Size: 66 KB
 
Oenothera serrulata  Nutt.
[=Calylophus serrulatus  (Nutt. ) Raven]
Mitchell County, Kansas
Perennial
Height: 6-30 inches
Family: Onagraceae - Evening Primrose Family
Flowering Period:   May, June, July, August
Also Called: Plains yellow primrose.
Stems: Erect or decumbent, few to many, simple or branched from base, glabrous or hairy.
Leaves: Alternate, simple, sessile, linear-oblong to narrowly lanceolate, 1/2 to 4 inches long, less than 1/2 inch wide, nearly glabrous or hairy above, gray-hairy below, often folded lengthwise; margins toothed or entire; tips pointed to rounded.
Inflorescences: Solitary flowers, in axils of upper leaves.
Flowers: 1-2 inches wide, floral tubes less than 3/5 inch long; sepals 4, distinctly keeled; petals 4, 1/4 to 3/4 inch long, about as wide, bright yellow, fading to pale yellow or pinkish; stamens 8; stigma disc-shaped, 4-lobed, extending nearly to tips of stamens.
Fruits: Capsules, linear-cylindric, 1/2 to 1 inch long, 4-angled, thick-walled, slightly grooved, silvery-hairy; seeds many, small, brown.
Habitat: Dry rocky, gravelly, or sandy prairies, hillsides, roadsides, and open woods.
Distribution: Throughout Kansas.
Forage Value: Serrate-leaf evening primrose is palatable and nutritious to livestock, particularly the new growth. It decreases on overgrazed rangeland.
Comments: Serrate-leaf evening primrose is drought resistant. In addition to an extensive root system, the leaves fold in the midday sun, reducing water loss through their surfaces.

Serrate-leaf evening primrose sepals and leaves
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Osborne County, Kansas
Serrate-leaf evening primrose stamens and stigma
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Russell County, Kansas
Serrate-leaf evening primrose
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Russell County, Kansas
Serrate-leaf evening primrose
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Mitchell County, Kansas
Serrate-leaf evening primrose
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Russell County, Kansas
Serrate-leaf evening primrose
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Riley County, Kansas
Serrate-leaf evening primrose
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Big Basin, Clark County, Kansas
Serrate-leaf evening primrose flower
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Mitchell County, Kansa
Serrate-leaf evening primrose
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Riley County, Kansas
Serrate-leaf evening primrose
129 KB
Riley County, Kansas
Serrate-leaf evening primrose flower
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Riley County, Kansas
Serrate-leaf evening primrose habit
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Clark County, Kansas
Serrate-leaf evening primrose
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Riley County, Kansas
Serrate-leaf evening primrose
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Riley County, Kansas
Serrate-leaf evening primrose
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Ottawa County, Kansas