Conium maculatum L.
Coefficient of Conservatism: *
Coefficient of Wetness: -3
Wetness Index: FACW
Physiognomy: Ad B-Forb

Roadsides, fields, disturbed places, clearings, banks and bluffs, shores. First collected in 1882 in Mackinac Co. but established at a number of places across Michigan by the 1890’s. The species has an unpleasant odor. It can grow to 2 m or even more in height; the purple-spotted, slightly glaucous stem, lacy foliage, and white umbels make it very conspicuous.

Although toxicity varies among plants and with the season, as well as the part of the plant, this is a very poisonous species, promptly producing symptoms when ingested and often death from respiratory failure. Both livestock and humans are affected. Socrates is the best known victim of poison-hemlock.


Allegan County
Baraga County
Bay County
Berrien County
Cheboygan County
Emmet County
Hillsdale County
Houghton County
Ionia County
Isabella County
Jackson County
Kalamazoo County
Kent County
Leelanau County
Lenawee County
Mackinac County
    Including Bois Blanc, Mackinac, Round Islands
Mason County
Newaygo County
Oakland County
Oceana County
Ogemaw County
Ottawa County
St. Clair County
Washtenaw County
Wayne County


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. May 25, 2022.