Lolium perenne L.
Common Name: RYEGRASS
Coefficient of Conservatism: *
Coefficient of Wetness: 3
Wetness Index: FACU
Physiognomy: Ad P-Grass

Roadsides, yards, and disturbed places; spreading in forests and on shores. An occasional weed or waif first collected in Ingham Co. in 1887; often planted as a cover crop but not so common out of cultivation as many of our forage grasses.

We have both var. perenne and var. aristatum Willd., the latter often recognized as a distinct species, L. multiflorum Lam. It differs from typical L. perenne in the following characters: lemmas awned (not awnless), 10 or more in a spikelet (not 10 or fewer); rachis scabrous on convex surface as well as edges (not on edges only); auricles prominent, elongate (not absent or small); leaf blades in young shoots inrolled at the margins (not merely folded lengthwise); plants annual or biennial (not perennial). The two taxa evidently hybridize, and our populations include so many specimens that are somewhat intermediate as to make recognition of two entities arbitrary.


Alcona County
Allegan County
Alpena County
Baraga County
Barry County
Bay County
Benzie County
Berrien County
Calhoun County
Charlevoix County
    Including Beaver Island
Cheboygan County
Chippewa County
Crawford County
Eaton County
Emmet County
Grand Traverse County
Gratiot County
Hillsdale County
Houghton County
Ingham County
Iosco County
Kalamazoo County
Kalkaska County
Kent County
Keweenaw County
    Only on Isle Royale
Lake County
Lapeer County
Leelanau County
Lenawee County
Mackinac County
Macomb County
Manistee County
Marquette County
Mason County
Mecosta County
Menominee County
Monroe County
Muskegon County
Newaygo County
Oakland County
Oscoda County
Ottawa County
Presque Isle County
Schoolcraft County
St. Clair County
St. Joseph 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. September 27, 2022.