Grindelia squarrosa (Pursh) Dunal. Curly-top Gumweed. Phen: Jul-Oct. Hab: Roadsides, other disturbed areas. Dist: ON west to BC, south to TX, CA, and n. Mexico (CHH, COA, and NLE); also adventive widely in the e. United States.

Origin/Endemic status: Native

Taxonomy Comments: Some authors (primarily Diggs et al. 1999 [NcTX] and Nesom 1990) afford segregate names for discoid plants loosely (?) referable to G. squarrosa. These perhaps warrant some recognition, especially since there are additional differences beyond head type. See Strother and Wetter (2006a) for succinct descriptions of some notable potential segregates.

Synonymy: = K4; = Grindelia squarrosa (Pursh) Dunal var. squarrosa – C, G, GrPl, Il, K1, SE1; > Grindelia nuda Alph.Wood – NcTx; > Grindelia nuda var. nuda; < Grindelia squarrosa (Pursh) Dunal – Ar, FNA20, K3, Mex, Mi, NE, Pa, Tat; > Grindelia squarrosa (Pursh) Dunal – NcTx; > Grindelia squarrosa (Pursh) Dunal var. nuda (Alph.Wood) A.Gray – F, NY, Tx; > Grindelia squarrosa (Pursh) Dunal var. quasiperennis Lunell – F; > Grindelia squarrosa (Pursh) Dunal var. serrulata (Rydb.) Steyerm. – F, Oh3; > Grindelia squarrosa (Pursh) Dunal var. squarrosa – F, NY, Oh3, Tx

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Wetland Indicator Status:

• Atlantic and Gulf Coastal Plain: FACU
• Eastern Mountains and Piedmont: FACU
• Great Plains: UPL
• Midwest: FACU
• Northcentral & Northeast: FACU

Heliophily: 9