Actaea pachypoda Elliott
Coefficient of Conservatism: 7
Coefficient of Wetness: 5
Wetness Index: UPL
Physiognomy: Nt P-Forb

Actaea pachypoda Ann Arbor Natural Area Preservation

Rich deciduous forests and northern hardwoods, less often under pine, cedar, or other conifers. Often growing with one or both color forms of A. rubra.

Readily distinguished from A. rubra in fruit, by its striking elongate raceme of porcelain-like berries on thick red stalks. In A. rubra, the raceme is more often compact and the pedicels remain very slender. Young flowering material, before the pedicels have begun to thicken, is more difficult to determine, although the peculiar tips of the petals are helpful (the sepals fall off very early). The broad stigma in A. pachypoda seems to be more clearly sessile (the style, if any, broad and thick beneath it) than in A. rubra, where the pistil tends to narrow somewhat beneath the stigma. Differences in leaf pubescence cannot be relied upon, although in A. pachypoda the leaves are more often glabrous or nearly so beneath, while in A. rubra there is usually at least some small pubescence along the veins beneath. A red-fruited form of A. pachypoda is known [f. rubrocarpa (Killip) Fernald] but seems to be very rare in Michigan, represented by one collection from Kent Co.

Specimens truly intermediate between the species are also rare but some hybridization occurs, producing Actaea ×ludovici B. Boivin. Suspected hybrids are known from Keweenaw and Oakland Cos., and doubtless occur elsewwhere. These hybrids are best discerned in fruit, and vary in berry color, as expected, but are often reddish berried, though typically not as dark as those of A. rubra. They differ most clearly in having intermediate pedicel widths; proportionately longer and thinner than those of A. pachypoda and only dull reddish in color, but thicker  than those of A. rubra, and with clearly thickened bases. Examining live material in the field, where contrasts with the likely parents can be readily made, is the best way of detecting these hybrids.



Alcona County
Alger County
Allegan County
Alpena County
Antrim County
Arenac County
    Including Charity Island
Baraga County
Barry County
Bay County
Benzie County
Berrien County
Branch County
Calhoun County
Charlevoix County
    Including Beaver Island
Cheboygan County
Chippewa County
    Including Drummond Island
Clare County
Clinton County
Crawford County
Delta County
Dickinson County
Eaton County
Emmet County
Gogebic County
Grand Traverse County
Hillsdale County
Houghton County
Huron County
Ingham County
Ionia County
Iosco County
Iron County
Isabella County
Jackson County
Kalamazoo County
Kalkaska County
Kent County
Keweenaw County
    Including Isle Royale
Lake County
Lapeer County
Leelanau County
    Including Fox Islands
    Including Manitou Islands
Lenawee County
Luce County
Mackinac County
    Including Bois Blanc, Mackinac, Round Islands
Macomb County
Manistee County
Marquette County
Mason County
Menominee County
Midland County
Montcalm County
Montmorency County
Muskegon County
Newaygo County
Oakland County
Ogemaw County
Ontonagon County
Osceola County
Oscoda County
Ottawa County
Presque Isle County
Saginaw County
Sanilac County
Schoolcraft County
Shiawassee County
St. Clair County
St. Joseph County
Tuscola 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. November 30, 2022.