Please try our next iteration of the Michigan Flora Online here. Beginning on February 1, 2023, will point to this new site.

The new site offers several benefits over the existing website, including real coordinate mapping, giving a clearer view of the density of documentation as well as more precision about plant distributions and their link to landforms. We will also have the ability to update species pages more regularly, both in terms of new collections and as more existing Michigan specimens are georeferenced. In addition, we have a better photo display, and offer indented keys.

Silphium integrifolium Michx.
Common Name: ROSIN WEED
Coefficient of Conservatism: 10
Coefficient of Wetness: 0
Wetness Index: FAC
Physiognomy: Nt P-Forb
Status: T

Michigan is at the northeastern edge of the range of this species of mostly wet prairies, savannas, and prairie fens. Our collections are from dry to wet prairies, sedge meadows, and moist open ground at borders of forests.

Showy and sometimes cultivated, collections from Mason and Mecosta Cos. are adventive, as is the Washtenaw Co. record from along a railway. Now sometimes also included in so called prairie plantings, and collected as "Persisting ...about 20 years" in such a planting in Lenawee Co. (not mapped).

See comments under Heliopsis on possible confusion with that genus.


Berrien County
Cass County
Kalamazoo County
Mason County
Mecosta County
Van Buren County
Washtenaw County


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. January 29, 2023.