Ambrosia trifida Linnaeus var. trifida . Phen: Jul-Nov. Hab: Floodplains, moist pastures, disturbed ground. Dist: NS and BC south to n. peninsular FL, Panhandle FL, TX, and CA.
Origin/Endemic status: Native
Taxonomy Comments: The distinction between var. trifida and var. texana (or at the specific rank A. trifida and A. aptera) warrants additional study.
Synonymy: = C, F, G, GrPl, Il, NE; = Ambrosia trifida L. – S; < Ambrosia trifida L. – Fl7, FNA21, K3, K4, Mi, Mo2, NY, Oh3, Ok, Pa, RAB, SE1, Tn, Va, WH3, McMillan & Prevost (2022)