Tufted Evening-primrose - Oenothera caespitosa
MNPS Threat Rank
Acaulescent perennial with a simple or branched caudex surmounting a taproot. Herbage strigose. Leaves oblanceolate, 2–15 cm long with entire to serrate margins. Flowers white, opening at night, turning pink the following morning; hypanthium 2–8 cm long; sepals 1–3 cm long; petals 15–35 mm long; stigma lobes 3–6 mm long. Capsule erect, narrowly ovoid to ellipsoid, 12–40 mm long, woody, vaguely 4-angled, usually bumpy, sometimes pedicellate, often partly below ground (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX)
Our plants are subspecies caespitosa
WA to SK, south to CA, NM, TX and Mexico (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
Observations in Montana Natural Heritage Program Database
Number of Observations:
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Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
Sandy or clay, usually sparsely-vegetated soil of open slopes, badlands, sandhills, roadsides; plains, valleys to subalpine (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX)
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus pensylvanicus
and Bombus impatiens
(Colla and Dumesh 2010).
- Literature Cited AboveLegend: View Online Publication
- Colla, S.R. and S. Dumesh. 2010. The bumble bees of southern Ontario: notes on natural history and distribution. Journal of the Entomological Society of Ontario 141: 39-68.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Jones, W. W. 1901. Preliminary flora of Gallatin County. M.S. Thesis. Bozeman, MT: Montana State College. 78 pp.
- Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
- Mackie, R.J. 1965. Range ecology and relationships of mule deer, elk, and cattle in the Missouri River breaks. Ph.D Dissertation. Bozeman, MT: Montana State University. 229 p.
- Martin, S.A. 1985. Ecology of the Rock Creek bighorn sheep herd, Beartooth Mountains, Montana. M.Sc. Thesis. Bozeman, MT: Montana State University. 152 p.
- Quire, R.L. 2013. The sagebrush steppe of Montana and southeastern Idaho shows evidence of high native plant diversity, stability, and resistance to the detrimental effects of nonnative plant species. M.Sc. Thesis. Bozeman, MT: Montana State University. 124 p.
- Rundquist, V.M. 1973. Avian ecology on stock ponds in two vegetational types in north-central Montana. Ph.D. Dissertation. Bozeman, MT: Montana State University. 112 p.
- Seipel, T.F. 2006. Plant species diversity in the sagebrush steppe of Montana. M.Sc. Thesis. Bozeman, MT: Montana State University. 87 p.