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Johnston's Knotweed - Polygonum sawatchense
Other Names:
Polygonum douglasii ssp. johnstonii
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General Description
Annual. Stems erect, simple or branched at the base, 5–35 cm. Leaves short-petiolate; blades 8–20 mm long, linear-oblong, reduced above; stipules lacerate, 2–10 mm long. Flowers 3–4 mm long, 1 to 4 in leaf axils; pedicels erect, 1–4 mm long; tepals green with white to pink margins. Achene 3-sided, 2–3 mm long, shiny black (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX ).
Range Comments
BC to SK south to CA, AZ and NM. One collection from an alpine, stony, calcareous slope in Beaverhead County (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX ).
Observations in Montana Natural Heritage Program Database
Number of Observations: 3
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Relative Density
Recency
(Observations spanning multiple months or years are excluded from time charts)
Habitat
Ecology
POLLINATORS 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).
Stewardship Responsibility
References
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