Collinsonia canadensis Linnaeus. Common name: Richweed, Northern Horsebalm. Phenology: Late Jul-Sep; Sep-Oct. Habitat: Cove forests, rich forests, especially over calcareous or mafic substrates. Distribution: QC, MI, and WI, south to Panhandle FL and LA. Recently found on Crowleys Ridge in the AR Coastal Plain.
Origin/Endemic status: Native
Synonymy ⓘ: = C, Fl6, G, Il, K4, Mi, Mo3, NE, NY, Pa, S, Tat, Tn, Va, W, WH3, WV, Shinners (1962b); = Collinsonia canadensis L. var. canadensis — F; < Collinsonia canadensis L. — RAB, Peirson, Cantino, & Ballard (2006); Collinsonia canadensis L. — (basionym)
Wetland Indicator Status:
- Atlantic and Gulf Coastal Plain: FAC (taxonomic split from wetland indicator species)
- Eastern Mountains and Piedmont: FAC (taxonomic split from wetland indicator species)
- Midwest: FAC (taxonomic split from wetland indicator species)
- Northcentral & Northeast: FAC (taxonomic split from wetland indicator species)
Heliophily ⓘ: 3
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Horticultural Information
Intro: Erect to ascending perennial found in the understory of cove and other rich forests, especially over calcareous or mafic substrates.
Stems: Stems 4-angled, few-branched, mostly smooth.
Leaves: Leaves opposite, petiolate (upper ones nearly sessile), oval, 2-8 in. long, coarsely toothed, smooth.
Inforescence:
Flowers: Flowers in a loose, wide-branching panicle, pale yellow, ½ in. long, bilaterally symmetric, tubular and 2-lipped (lower lip prominently fringed), with 2 long-protruding stamens and an elongated style.
Fruits:
Comments: Ranging broadly over much of temperate eastern North American, this mint gives off a lemony scent when a plant is bruised or crushed.
Height: 2-3 ft.
plant sale text:
bloom table text:
description: Erect to ascending perennial found in the understory of cove and other rich forests, especially over calcareous or mafic substrates.
stems: Stems 4-angled, few-branched, mostly smooth.
leaves: Leaves opposite, petiolate (upper ones nearly sessile), oval, 2-8 in. long, coarsely toothed, smooth.
inflorescence:
flowers: Flowers in a loose, wide-branching panicle, pale yellow, ½ in. long, bilaterally symmetric, tubular and 2-lipped (lower lip prominently fringed), with 2 long-protruding stamens and an elongated style.
fruits:
comments: Ranging broadly over much of temperate eastern North American, this mint gives off a lemony scent when a plant is bruised or crushed.
cultural notes:
germination code:
native range: eastern North America