Silphium laciniatum Linnaeus. Phen: Jun-Sep. Hab: Prairies, limestone barrens, calcareous glades, also sometimes cultivated (including outside of its native distribution). Dist: S. ON, MI. WI, s. MN, and e. SD south to se. TN, s. AL, c. MS, s. LA, c. TX, and n. NM. Populations discovered at outlying sites to the east (Chester Co. VA, Chain Bridge in Washington DC in the 1880s, etc.) are ambiguous as to nativity (R. Wright, pers. comm. 2012).
Origin/Endemic status: Native
Synonymy: = Ar, C, FNA21, G, GrPl, K3, K4, Mi, NcTx, NY, Oh3, SE1, Tn, Tx; = n/a – Pa; > Silphium laciniatum L. var. laciniatum – F, Il, K1, Perry (1937); > Silphium laciniatum L. var. robinsonii L.M.Perry – F, Il, K1, Perry (1937)