Leathery Knotweed - Polygonum achoreum
MNPS Threat Rank
Annual, often white with mildew. Stems prostrate to ascending, usually branched at the base,10–30 cm. Leaves short-petiolate; the blades ovate, 7–25 cm long; stipules 5–8 mm long, lacerate. Flowers 3–4 mm long, 1 to 3 in leaf axils; pedicels erect, 1–2 mm long; tepals green with yellowsih margins, the outer keeled at the tip. Achene 3-angled, yellow-brown, 2–3 mm long (Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX)
AK to QC south to NV, KS, OH, and NY (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)
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus bifarius
, Bombus flavifrons
, Bombus frigidus
, Bombus melanopygus
, Bombus sylvicola
, Bombus occidentalis
, Bombus pensylvanicus
, Bombus insularis
, and Bombus kirbiellus
(Macior 1974, 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.
- Macior, L.M. 1974. Pollination ecology of the Front Range of the Colorado Rocky Mountains. Melanderia 15: 1-59.
- 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.
- 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.