Persicaria setacea (Baldwin) Small. Section: Persicaria. Common name: Swamp Smartweed. Phenology: Jul-Nov. Habitat: Swamp forests, bottomland forests. Distribution: MA, MI, MO, and OK south to s. FL and TX. Discovered in Ripley County, IN (S. Namestnik, pers.comm. 2022).
Origin/Endemic status: Native
Synonymy ⓘ: = Ar, Fl4, FNA5, Il, K4, Mo3, NE, NY, Pa, S, S13, Tn, Tx, Va; = Polygonum hydropiperoides Michx. var. setaceum (Baldwin) Gleason — C, G; = Polygonum setaceum Baldwin — GW2, NcTx, RAB, Tat, W, WH3, Horton (1972), Mitchell & Dean (1978); > Polygonum setaceum Baldwin var. interjectum Fernald — F; > Polygonum setaceum Baldwin var. setaceum — F; > Polygonum setaceum Baldwin var. tonsum Fernald — F. Basionym: Polygonum setaceum Baldwin 1821
Links to other floras: = Persicaria setacea - FNA5
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Wetland Indicator Status:
- Atlantic and Gulf Coastal Plain: OBL
- Eastern Mountains and Piedmont: OBL
- Great Plains: OBL
- Midwest: OBL
- Northcentral & Northeast: OBL
Heliophily ⓘ: 6
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Horticultural Information
Intro: Erect perennial of swamp and bottomland forests, brackish and maritime swamps.
Stems: Stems simple or branching from middle or upper nodes, slightly ridged, hairy.
Leaves: Leaves alternate, petiolate and with a long-fringed and hairy membranous sheath (ocrea) where petiole joins stem; lance-shaped to linear; 2 1/4-6 in. long; smooth or rough-hairy above and smooth or hairy beneath.
Inforescence:
Flowers: Flowers in erect, dense spikes at ends of branches; greenish-white to pinkish; less than 1/4 in. long; consisting of 5 tepals that are joined at the base and usually not fully spreading.
Fruits:
Comments:
Height: 1 1/2-4 ft.
plant sale text:
bloom table text:
description: Erect perennial of swamp and bottomland forests, brackish and maritime swamps.
stems: Stems simple or branching from middle or upper nodes, slightly ridged, hairy.
leaves: Leaves alternate, petiolate and with a long-fringed and hairy membranous sheath (ocrea) where petiole joins stem; lance-shaped to linear; 2 1/4-6 in. long; smooth or rough-hairy above and smooth or hairy beneath.
inflorescence:
flowers: Flowers in erect, dense spikes at ends of branches; greenish-white to pinkish; less than 1/4 in. long; consisting of 5 tepals that are joined at the base and usually not fully spreading.
fruits:
comments:
cultural notes:
germination code:
native range:
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