Grindelia squarrosa (Pursh) Dunal
Common Name: GUMWEED
Coefficient of Conservatism: *
Coefficient of Wetness: 3
Wetness Index: FACU
Physiognomy: Ad B-Forb

Grindelia squarrosa flowering head top J. Morefield flowering head top

Roadsides, railroads, fields, sandy and gravelly banks, and disturbed sites including vacant lots, gravel pits, and filled land. Native to the prairies and beyond, west of the Great Lakes. Adventive eastward and first collected in Michigan 1901–1905 in Kent, Marquette, St. Clair, and Wayne Cos.

A very distinctive plant, often bushy-branched, with attractive yellow heads and very resinous, curly-looking phyllaries.


Alpena County
Antrim County
Arenac County
Barry County
Benzie County
Berrien County
Branch County
Cass County
Charlevoix County
    Including Beaver Island
Cheboygan County
Clare County
Crawford County
Delta County
Dickinson County
Emmet County
Gogebic County
Grand Traverse County
Ingham County
Isabella County
Kalamazoo County
Kent County
Lake County
Lapeer County
Leelanau County
Lenawee County
Mackinac County
    Only on Bois Blanc, Mackinac, Round Islands
Marquette County
Muskegon County
Newaygo County
Oakland County
Oscoda County
Ottawa County
Sanilac County
Schoolcraft County
St. Clair County
Van Buren County
Washtenaw County
Wayne County
Wexford County


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. October 22, 2021.