Medicago sativa L.
Common Name: ALFALFA
Coefficient of Conservatism: *
Coefficient of Wetness: 5
Wetness Index: UPL
Physiognomy: Ad P-Forb

Medicago sativa B. S. Walters

Roadsides, fields, and disturbed ground everywhere. A very important and variable crop plant, long cultivated and first collected in Michigan in 1859 in Washtenaw Co. Apparently a human-selected tetraploid hybrid of uncertain origin, widely naturalized.

The corolla of typical alfalfa is blue-purple (white in albinos), and the fruit is coiled at least 1.5–2 times at maturity. A yellow-flowered alfalfa with straight to C-shaped fruits has been called M. falcata L. or treated as a subspecies of M. sativa. It has not been collected in Michigan (although one cannot be certain of yellow-flowered plants lacking fruit). Our relatively frequent yellow-flowered plants are hybrids, which have been called M. ×varia Martyn. Insofar as they have fruit, they are indeed intermediate. The corollas may also be blue-green or variegated.

Locations

Alger County
Allegan County
Alpena County
Antrim County
Arenac County
Baraga County
Barry County
Benzie County
Berrien County
Cass County
Charlevoix County
    Including Beaver Island
Cheboygan County
Chippewa County
Clare County
Clinton County
Crawford County
Delta County
Dickinson County
Eaton County
Emmet County
Genesee County
Gladwin County
Grand Traverse County
Hillsdale County
Houghton County
Huron County
Ingham County
Ionia County
Isabella County
Jackson County
Kalamazoo County
Kent County
Keweenaw County
Lake County
Lapeer County
Leelanau County
    Including Fox Islands
    Including Manitou Islands
Lenawee County
Livingston County
Mackinac County
    Including Bois Blanc, Mackinac, Round Islands
Marquette County
Mason County
Mecosta County
Menominee County
Monroe County
Montcalm County
Montmorency County
Muskegon County
Oakland County
Oceana County
Otsego County
Ottawa County
Presque Isle County
Roscommon County
Sanilac County
Shiawassee County
St. Clair 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. December 11, 2017. http://www.michiganflora.net/species.aspx?id=1332.