Urtica gracilis W. Aiton ssp. gracilis . Common name: American Stinging Nettle. Phenology: May-Jul; Jul-Sep. Habitat: Bottomland forests and edges, particularly over limestone or mafic rocks. Distribution: NL (Labrador) and NS west to AK, south to sw. VA, w. NC, s. OH, s. IL, s. MO, n. TX, s. NM, and se. AZ.

Origin/Endemic status: Native

Taxonomy Comments: The native stinging nettle of North America is best treated as specifically distinct from U. dioica of Europe. Woodland (1982) and Woodland, Bassett, Crompton, & Forget (1982) showed that U. gracilis differs from U. dioica in a variety of morphologic characters (see key), chromosome number (2n = 26 for U. gracilis, 2n = 52 for U. dioica), breeding system (monoecy vs. dioecy), and distribution (North American vs. Eurasian); furthermore, the two taxa could not be crossed. Woodland (1982) chose subspecific status, apparently to emphasize the close relationship of the two (and a third taxa in w. North America). The combination of morphological distinctiveness, allopatry, major differences in species biology, and incompatibility warrants separation as species. F (as U. procera), G (as U. dioica var. procera) and S include NC in the range; Woodland (1982), however, showed the range as extending only south to VA. Henning et al. (2014) further validated the idea that American "U. dioica" is specifically distinct from European U. dioica.

Synonymy ⓘ: = Can, NY, POWO, Grosse-Veldmann & Weigend (2017), Henning et al (2014); = Urtica dioica L. ssp. gracilis (Aiton) Selander — FNA3, GrPl, K4, Mi, Mo3, NE, NS, Pa, Tn, Woodland (1982); = Urtica dioica L. var. procera (Muhl. ex Willd.) Wedd. — C; = Urtica gracilis Aiton — Ar, Il, S, S13, Tx, Va, WV; < Urtica dioica L. — RAB, Tat, W; > Urtica dioica L. var. procera (Muhl. ex Willd.) Wedd. — G; > Urtica gracilis Aiton — F; > Urtica procera Muhl. — F; > Urtica viridis Rydb. — F, G. Basionym: Urtica gracilis Aiton 1789

Links to other floras: = Urtica dioica ssp. gracilis - FNA3

Show in key(s)

Show parent genus | Show parent in key(s)

Wetland Indicator Status:

• Atlantic and Gulf Coastal Plain: FAC (taxonomic split from wetland indicator species)
• Eastern Mountains and Piedmont: FACU (taxonomic split from wetland indicator species)
• Great Plains: FAC (taxonomic split from wetland indicator species)
• Midwest: FACW (taxonomic split from wetland indicator species)
• Northcentral & Northeast: FAC (taxonomic split from wetland indicator species)

Heliophily ⓘ: 3