Mountain Starthistle - Centaurea montana
Montane Knapweed, Mountain Cornflower, Mountain Bluet
Perennials, 30-70 cm tall. Stems simple or sparingly branched, sparsely tomentose. Leaves mostly 7-18 mm long, 1-4 mm wide, entire or nearly so. Inflorescence corymbiform or heads solitary; peduncles 1.5-7 cm long; involucres 2-2.5 chm high and as broad or broader; bracts imbricate, lanceolate to ovate-triangular with prominent blackish pectinate-lacerate margins extending to the base or nearly so, lacking a definte terminal appendage (except sometimes the inner); outer flowers blue, enlarged and subradiate; inner ones purplish; anthers blackish-purple; achenes short-hairy (pappus 1-1.5 mm long) (adapted from: Welsh et al., 1993, A Utah Flora, 2nd ed.).
Introduced as ornamental; scattered across northern parts of North America, less so in Great Plains and southern tier states and Southeast (Kartesz in prep. 2012).
Observations in Montana Natural Heritage Program Database
Number of Observations:
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(Observations spanning multiple months or years are excluded from time charts)
Persisting and sometimes spreading from cultivation.
The following animal species have been reported as pollinators of this species or genera where their geographic ranges overlap: Bombus vagans
, Bombus bifarius
, Bombus centralis
, Bombus fervidus
, Bombus rufocinctus
, Bombus ternarius
, Bombus terricola
, Bombus occidentalis
, Bombus griseocollis
, Bombus impatiens
, Bombus insularis
, and Bombus suckleyi
(Thorp et al. 1983, Johnson 1986, Colla and Dumesh 2010, Koch et al. 2012, Williams et al. 2014, Tripoldi and Szalanski 2015).
- 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.
- Flora of North America Editorial Committee. 2006. Flora of North America North of Mexico. Vol. 19. Magnoliophyta: Asteridae, part 6: Asteraceae, part 1. Oxford Univ. Press, New York. xxiv + 579 pp.
- Johnson, R.A. 1986. Intraspecific resource partitioning in the bumble bees Bombus ternarius and B. pennsylvanicus. Ecology 67:133-138.
- Koch, J., J. Strange, and P. Williams. 2012. Bumble bees of the western United States. Washington, DC: USDA Forest Service, Pollinator Partnership. 143 p.
- Thorp, R.W., D.S. Horning, and L.L. Dunning. 1983. Bumble bees and cuckoo bumble bees of California (Hymenoptera: Apidae). Bulletin of the California Insect Survey 23:1-79.
- Tripoldi, A.D. and A.L. Szalanski. 2015. The bumble bees (Hymenoptera: Apidae: Bombus) of Arkansas, fifty years later. Journal of Melittology 50: doi: http://dx.doi.org/10.17161/jom.v0i50.4834
- Williams, P., R. Thorp, L. Richardson, and S. Colla. 2014. Bumble Bees of North America. Princeton, NJ. Princeton University Press.
- Additional ReferencesLegend: View Online Publication
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- Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.