Cypripedium parviflorum Salisb.
Common Name: YELLOW LADY-SLIPPER
Synonym: Cypripedium calceolus
Coefficient of Conservatism: 5
Coefficient of Wetness: 0
Wetness Index: FAC
Physiognomy: Nt P-Forb

C. calceolus of Michigan Flora.

In a great diversity of habitats except the driest: moist forests (coniferous, mixed, deciduous), fens, meadows, borders of forests and clearings, often under cedar, and mostly in clearly calcareous soils. Two somewhat intergrading varieties occur; var. pubescens (Willd.) O. W. Knight is large-flowered (lip (2.2–) 2.5–4.8 cm long), with greenish or yellowish, slightly twisted lateral petals, and hairy upper sheathing bracts, and var. makasin (Farw.) Sheviak has a smaller flower (lip 1.5–2.9 cm), with dark purple-brown, twisted lateral petals, and nearly glabrous upper sheathing bracts. Variety pubescens occurs throughout Michigan, often in forests, whereas var. makasin is found mostly in the lower half of the Lower Peninsula, with a few records north to Drummond Island, and occurs frequently in swamps, shrub thickets, fens, and wet meadows. Variety makasin was discussed as C. calceolus var. parviflorum in Michigan Flora.

Locations

Alcona County
Alger County
Allegan County
Alpena County
Antrim County
Arenac County
Baraga County
Barry County
Bay County
Benzie County
Berrien County
Calhoun County
Cass County
Charlevoix County
    Including Beaver Island
Cheboygan County
Chippewa County
    Including Drummond Island
Clare County
Clinton County
Delta County
Dickinson County
Eaton County
Emmet County
Gladwin County
Gogebic County
Grand Traverse County
Gratiot 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
Lapeer County
Leelanau County
    Including Fox Islands
    Including Manitou Islands
Lenawee County
Livingston County
Luce County
Mackinac County
    Including Bois Blanc, Mackinac, Round Islands
Macomb County
Marquette County
Mecosta County
Menominee County
Midland County
Montcalm County
Montmorency County
Muskegon County
Oakland County
Ogemaw County
Ontonagon County
Osceola County
Oscoda County
Otsego County
Presque Isle County
Roscommon County
Saginaw County
Sanilac County
Schoolcraft County
St. Clair County
St. Joseph County
Tuscola County
Washtenaw County
Wayne County

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. September 26, 2017. http://www.michiganflora.net/species.aspx?id=1806.