Slender Pondweed

Potamogeton pusillus

Alternate names
Small Pondweed

Leaves
Leaves are arranged alternately along the stem and are linear or ribbon-like in outline, approximately 1 to 2 inches long and only a few millimeters wide. A pair of glands occurs at the bases of the leaves, which are often difficult to see with the naked eye. The leaves also have stipules that are separate from the leaf bases and are approximately 1/3 to 2/3 inch long.

Stems
Root at the nodes when in contact with the ground.

Flowers
Small flower spikes occur on short stalks (peduncles) that arise from the area between the leaf bases and the stems.

Fruit
An achene.

Identifying Characteristics
The alternately arranged narrow, ribbon-like leaves and stipules are both characteristics that help to distinguish this weed from other aquatic plants. Slender pondweed is often confused with Southern Naiad (Najas guadalupensis), however the leaves of this aquatic are arranged oppositely along the stem and have toothed margins unlike those of slender pondweed.

Office of Programs

University of Missouri

Slender Pondweed

Potamogeton pusillus