Symphyotrichum lanceolatum (Willd.) G. L. Nesom
Common Name: PANICLED ASTER
Synonym: Aster lanceolatus
Coefficient of Conservatism: 2
Coefficient of Wetness: -3
Wetness Index: FACW
Physiognomy: Nt P-Forb

Aster lanceolatus of Michigan Flora.

One of our commonest asters, especially in moist open ground including shores, river banks, edges of forests and swamps, meadows, ditches and swales, interdunal flats; wet prairies, marshes, fens; fields, along old railroads, roadsides.

Often forming large colonies from long-creeping rhizomes, but highly variable. Plants with large blue-rayed heads superficially resemble S. robynsianum, but differ in less clasping leaf bases, more imbricate phyllaries, and tendency to shorter leaves and more heads. Such plants represent S. lanceolatum var. hesperium (A. Gray) G. L. Nesom and are known from Benzie, Delta, Manistee, Osceola, and Schoolcraft Cos. Plants with pubescence uniform (rather than in lines, or absent) on the middle and lower internodes have been named var. hirsuticaule Semple & Chmiel. Plants with quite small heads (involucre under 5 mm long), very numerous and crowded on branches of the inflorescence, have been called var. interior (Wiegand) Semple & Chmiel. Plants with stems glabrous or pubescent only in lines and with heads not crowded include plants with broadly oblanceolate leaves (var. latifolium (Semple & Chmiel.) G. L. Nesom) and plants with narrow, linear to oblanceolate leaves (var. lanceolatum). These last four varieties appear to be widespread, but we have no abundance data.

Sometimes this species is confused with S. pilosum, and indeed these two species appear to hybridize, but besides its unique phyllaries, involucre shape, and cespitose habit, Symphyotrichum pilosum tends to have the pappus of the disk florets shorter than the corollas, while in S. lanceolatum and its allies, the pappus equals or exceeds the disk corollas. Plants intermediate with S. puniceum and especially S. firmum seem to be more frequent than some supposed hybrids. And a number of plants resembling S. lanceolatum but with deeply lobed disk corollas presumably have resulted from hybridization with S. lateriflorum.

Locations

Alcona County
Alger County
Allegan County
Alpena County
Arenac 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
Eaton County
Emmet County
Genesee County
Gogebic County
Grand Traverse County
Gratiot County
Hillsdale County
Houghton County
Huron County
Ingham County
Ionia County
Iron County
Jackson County
Kalamazoo County
Kalkaska County
Kent County
Keweenaw County
    Including Isle Royale
Lake County
Lapeer County
Leelanau County
Lenawee County
Livingston County
Luce County
Mackinac County
    Including Bois Blanc, Mackinac, Round Islands
Macomb County
Manistee County
Marquette County
Mason County
Mecosta County
Menominee County
Monroe County
Montcalm County
Montmorency County
Muskegon County
Newaygo County
Oakland County
Oceana County
Ogemaw County
Ontonagon County
Osceola County
Oscoda County
Otsego County
Ottawa County
Presque Isle County
Roscommon County
Sanilac County
Schoolcraft County
Shiawassee County
St. Clair County
Tuscola 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 18, 2017. http://michiganflora.net/species.aspx?id=485.