Lactuca canadensis L.
Common Name: WILD LETTUCE, TALL LETTUCE
Coefficient of Conservatism: 2
Coefficient of Wetness: 3
Wetness Index: FACU
Physiognomy: Nt B-Forb

In much the same diverse habitats as L. biennis: borders and trails in forests; promptly invading disturbed sites and clearings; sandy pine plains, conifer swamps, rocky ground, shores, fields; roadsides and railroads.

This species and L. biennis are the two widespread common native wild lettuces in Michigan, and they can be easily separated by pappus color: silky white in L. canadensis and dark in L. biennis. The two species are known to hybridize but presumed hybrids, with intermediate characters, are apparently quite scarce in Michigan.

Some plants have many of the leaves unlobed and ± lanceolate, but usually the leaves are all or mostly lobed and the lobes tend to be narrowly lanceolate in contrast with the broad lobes in L. biennis. The foliage is amazingly variable in both species.

Locations

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
Crawford County
Delta County
Dickinson County
Emmet County
Gogebic County
Grand Traverse County
Gratiot County
Hillsdale County
Houghton County
Huron County
Ingham 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
Livingston County
Luce County
Mackinac County
    Including Bois Blanc, Mackinac, Round Islands
Macomb County
Manistee County
Marquette County
Mason County
Mecosta County
Midland County
Monroe County
Muskegon County
Newaygo County
Oakland County
Oceana County
Ogemaw County
Ontonagon County
Oscoda County
Otsego County
Ottawa County
Presque Isle County
Roscommon County
Sanilac County
Schoolcraft County
St. Clair County
St. Joseph County
Van Buren 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 12, 2017. http://michiganflora.net/species.aspx?id=385.