Western Hairy Rockcress - Arabis hirsuta
Arabis eschscholtziana, Arabis pycnocarpa
MNPS Threat Rank
Biennial or short-lived perennial. Stems 15–60 cm, simple or branched at the base. Basal leaves oblong with wavy to serrate margins, 2–12 cm long. Stem leaves lanceolate, auriculate-clasping. Vestiture of simple or branched hairs below, glabrous above. Petals 4–9 mm long. Fruits 2–5 cm × up to 1 mm, strictly erect. Our plants are variety pycnocarpa (M.Hopkins) Rollins (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX)
AK to QC south to CA, NM, MN and GA (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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(Observations spanning multiple months or years are excluded from time charts)
Sparsely vegetated, often disturbed, often stony soil of meadows, open forest; 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 bimaculatus
, Bombus griseocollis
, 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?
- Forcella, F. 1977. Flora, chorology, biomass and productivity of the Pinus albicaulis-Vaccinium scoparium association. M.S. Thesis. Bozeman, MT: Montana State University. 99 pp.
- 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.
- 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.
- Seipel, T.F. 2006. Plant species diversity in the sagebrush steppe of Montana. M.Sc. Thesis. Bozeman, MT: Montana State University. 87 p.
- Simanonok, M. 2018. Plant-pollinator network assembly after wildfire. Ph.D. Dissertation. Bozeman, MT: Montana State University. 123 p.