Field Sowthistle - Sonchus arvensis
Perennial Sow-thistle, Perennial Sowthistle, Corn Sow Thistle, Gutweed, Swine Thistle, Tree Sow Thistle
Rhizomatous perennial. Stems erect, 30–140 cm, sometimes branched above. Leaves linear-oblanceolate, pinnately lobed, 4–30 cm long, winged-petiolate below to sessile and auriculate above. Involucres 1–2 cm high; phyllaries glabrous or rarely stipitate-glandular. Ray ligules 7–13 mm long. Achenes brown, 2–4 mm long, minutely bumpy (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX)
We have subspecies arvensis
Introduced; across most of North America.
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)
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus vagans
, Bombus bifarius
, Bombus fervidus
, and Bombus terricola
(Thorp et al. 1983, 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.
- 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.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Lesica, P., M.T. Lavin, and P.F. Stickney. 2012. Manual of Montana Vascular Plants. Fort Worth, TX: BRIT Press. viii + 771 p.
- Simanonok, M. 2018. Plant-pollinator network assembly after wildfire. Ph.D. Dissertation. Bozeman, MT: Montana State University. 123 p.