Polygonum erectum Linnaeus. Common name: Erect Knotweed. Phenology: Jun-Oct; Jul-Oct. Habitat: Bottomland forests, streambanks, disturbed areas, open places. Distribution: ME, ON, and AB south to GA, LA, and NM.
Origin/Endemic status: Native
Synonymy ⓘ: = Ar, C, Can, F, FNA5, GrPl, Il, K4, Mi, Mo3, NE, NY, Pa, RAB, S, S13, Tn, Va, W, WV, Horton (1972), Mitchell & Dean (1978). Basionym: Polygonum erectum L. 1753
Links to other floras: = Polygonum erectum - FNA5
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Wetland Indicator Status:
- Atlantic and Gulf Coastal Plain: FACU
- Eastern Mountains and Piedmont: FACU
- Great Plains: FAC
- Midwest: FACU
- Northcentral & Northeast: FACU
Heliophily ⓘ: 7
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© Keith Bradley | Original Image ⭷
© Gary P. Fleming | Original Image ⭷
© Radford, Ahles and Bell | Original Image ⭷Feedback
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Horticultural Information
Intro: Erect-ascending annual of alluvial fields, stream banks, sand and gravel bars and open, disturbed areas.
Stems: Stems freely branched, hard and ribbed, with somewhat swollen nodes.
Leaves: Leaves alternate, short-petiolate and with a silvery membranous sheath (ocrea) where petiole joins stem, elliptic to lance-shaped, 1/2-3 in. long, firm, yellowish-green.
Inforescence:
Flowers: Flowers in sessile to short-stalked, axillary clusters of 1-5; greenish-white; 1/8 in. wide; consisting of 5 green, oblong tepals with bluntly rounded tips and yellow to whitish margins.
Fruits: Fruit a tiny, brown achene.
Comments:
Height: 8-30 in.
plant sale text:
bloom table text:
description: Erect-ascending annual of alluvial fields, stream banks, sand and gravel bars and open, disturbed areas.
stems: Stems freely branched, hard and ribbed, with somewhat swollen nodes.
leaves: Leaves alternate, short-petiolate and with a silvery membranous sheath (ocrea) where petiole joins stem, elliptic to lance-shaped, 1/2-3 in. long, firm, yellowish-green.
inflorescence:
flowers: Flowers in sessile to short-stalked, axillary clusters of 1-5; greenish-white; 1/8 in. wide; consisting of 5 green, oblong tepals with bluntly rounded tips and yellow to whitish margins.
fruits: Fruit a tiny, brown achene.
comments:
cultural notes:
germination code:
native range:
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