Potamogeton amplifolius Tuck.
Common Name: LARGE-LEAVED PONDWEED
Coefficient of Conservatism: 6
Coefficient of Wetness: -5
Wetness Index: OBL
Physiognomy: Nt P-Forb

Potamogeton amplifolius flowers G. E. Crow flowers

In lakes and larger rivers, usually at depths less than 3 m.

Some specimens of P. praelongus, especially from deep water (1.5–2 m or more), may have only rounded or even somewhat tapered leaf bases, and hence could run here in the key. They may, however, generally be distinguished from P. amplifolius by their very strongly whitish stipules and at most slightly tapered subsessile leaf bases. In P. amplifolius the stipules, while also prominent, are strongly tinged with brown or green and, particularly in deep water, the leaves are strongly narrowed at the base and/or definitely petiolate. The leaves of P. praelongus tend to have fewer nerves than those of P. amplifolius and are, of course, never floating.

Locations

Alcona County
Alger County
Allegan County
Alpena County
Antrim County
Arenac County
Baraga County
Barry County
Benzie County
Berrien County
Branch 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
Emmet County
Gogebic County
Grand Traverse County
Gratiot County
Hillsdale County
Houghton County
Ingham County
Iosco County
Iron County
Jackson County
Kalamazoo County
Kent County
Keweenaw County
    Including Isle Royale
Lake County
Lapeer County
Leelanau County
    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
Missaukee County
Montcalm County
Montmorency County
Muskegon County
Newaygo County
Oakland County
Ogemaw County
Ontonagon County
Osceola County
Otsego County
Ottawa County
Presque Isle County
Roscommon County
Schoolcraft County
St. Clair County
St. Joseph County
Van Buren County
Washtenaw County
Wayne County
Wexford County

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 15, 2017. http://michiganflora.net/species.aspx?id=2320.