USGS - science for a changing world

Northern Prairie Wildlife Research Center

  Home About NPWRC Our Science Staff Employment Contacts Common Questions About the Site

Aquatic and Wetland Vascular Plants of the Northern Great Plains

55. Potamogetonaceae, the Pondweed Family

1. Potamogeton L. -- Pondweed

11. Potamogeton natans L. -- Floatingleaf pondweed

Stems slightly compressed, 0.8-2 mm thick, simple or rarely branched, to 2 m long. Submersed leaves reduced to linear, bladeless phyllodes, these often disintegrating with age, 10-20 cm long, 1-2 mm wide, tapering to an obtuse tip. Floating leaves ovate-lanceolate to ovate-elliptic, 3-10 cm long, 1-5 cm wide, mostly 19- to 35-nerved, acute to obtuse at the tip, rounded to cordate at the base; petioles usually much exceeding the blade in length, usually forming an angle with the blade at their juncture; stipules free, fibrous, persistent or shredding with age, 4-10 cm long. Spikes dense, cylindric, 2-5 cm long; peduncles thicker than the stem, 3-10 cm long. Fruits greenish-brown to brown, obliquely elliptic-obovoid, 3-5 mm long, often pitted on the sides, the dorsal keel sharp or rounded with age, the lateral keels obscure. Jul--Aug. Shallow to rather deep water of lakes and ponds; frequent in the Turtle Mts., ND, and NE Sand Hills, otherwise uncommon; (Circumboreal, in N.Amer. s to PA, IN, IA, n KS, NM, AZ and CA).
GIF- Distribution Map

Map key

Previous Section -- Potamogeton illinoensis Morong -- Illinois pondweed
Return to Family -- Potamogetonaceae - The Pondweed Family
Next Section -- Potamogeton nodosus Poir. -- Longleaf pondweed

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Webmaster
Page Last Modified: Saturday, 02-Feb-2013 06:45:35 EST
Sioux Falls, SD [sdww55]