Cornus amomum Mill.
Coefficient of Conservatism: 2
Coefficient of Wetness: -3
Wetness Index: FACW
Physiognomy: Nt Shrub

Cornus amomum B. S. Walters

Wet (very rarely upland) sites: marshes, swamps (including cedar-tamarack), bogs and fens; margins of ponds, lakes, and streams and on banks of streams and rivers; often forming dense thickets at the edges of swamps and bodies of water.

Most of our specimens are C. amomum subsp. obliqua (Raf.) J. S. Wilson. Subspecies amomum has been collected in Michigan only along fence-rows and fields in Monroe Co.; it has the underside of the leaf blades not papillose and the veins with mostly rust-colored hairs. In subsp. obliqua, the lower leaf surface is usually very minutely and densely papillose [20×–30×] and the hairs along the veins are often mostly if not entirely whitish. There are also differences in leaf shape; the blades of subsp. obliqua is lance-ovate (relatively narrower and more cuneate at the base), and they are also pale beneath, whence the common name. New young shoots of C. amomum (especially the petioles and branchlets) have mostly rust-colored hairs, while in C. foemina the new shoots (and the inflorescence) are glabrous or with very sparse mostly or entirely whitish hairs. Hybrids between this species and C. foemina have been found in several counties, and are intermediate in length of calyx lobes, pubescence, fruit color, inflorescence shape, and other characters; they have mostly inviable pollen.


Allegan County
Alpena County
Antrim County
Arenac County
    Only on Charity Island
Barry County
Bay County
Benzie County
Berrien County
Branch County
Calhoun County
Cass County
Charlevoix County
    Including Beaver Island
Cheboygan County
Chippewa County
    Only on Drummond Island
Clare County
Clinton County
Delta County
Eaton County
Emmet County
Genesee County
Gladwin County
Grand Traverse County
Gratiot County
Hillsdale County
Huron County
Ingham County
Ionia County
Isabella County
Jackson County
Kalamazoo County
Kalkaska County
Kent County
Lake County
Lapeer County
Leelanau County
    Including Manitou Islands
Lenawee County
Livingston County
Mackinac County
Macomb County
Manistee County
Mason County
Mecosta County
Menominee County
Midland County
Monroe County
Montcalm County
Montmorency County
Muskegon County
Newaygo County
Oakland County
Oceana County
Osceola County
Ottawa County
Presque Isle County
Roscommon County
Saginaw County
Sanilac County
Schoolcraft County
Shiawassee County
St. Clair County
Van Buren County
Washtenaw County
Wayne County


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. August 15, 2022.