Geranium robertianum L.
Common Name: HERB ROBERT
Coefficient of Conservatism: 3
Coefficient of Wetness: 3
Wetness Index: FACU
Physiognomy: Nt A-Forb

Rich deciduous forests (oak-hickory or more often beech-maple), especially in clearings, along roads and trails, and at borders; rocky openings, gravelly shores, generally a calciphile; rarely associated with cedar. A circumpolar species, presumably native in our area although sometimes occurring in disturbed places. Sometimes considered introduced in western North America.

Reported by the First Survey, though no specimens appear to have survived; the first collection in Michigan dates from 1861, on Mackinac Island, and for some years, almost all of the collections were from or near the shores of the Great Lakes, especially northwards and on Islands. The first collection from an inland County in southern Michigan was by Emma Cole in Kent Co., in 1898, but only more recently has it been found widely inland and throughout southern Michigan, so it appears to have expanded its range in the state. Recent occurrences as an annoying weed in gardens and other urbanized and dirturbed sites may well represent plants more recently introduced, perhaps from Europe.

The whole plant has a strong and rather unpleasant scent, quite evident especially after specimens have been shut in a confined space, not entirely unlike that of Solanum dulcamara.



Alger County
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    Including Beaver Island
Cheboygan County
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    Including Drummond Island
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    Including Fox Islands
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MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. September 27, 2022.