Submerged Vegetation

Submerged plants are rooted with most of their vegetative mass below the water surface, although some portions may stick above the water.  One discerning characteristic of submerged plants is their flaccid or soft stems, which is why they do not usually rise above the water’s surface.

Coontail: Coontail is a dark olive-green, rootless submerged plant that often forms dense colonies. Leaves are relatively stiff, whorled with many forks and small teeth along one edge. The tips of branches are crowded with leaves giving it a “coontail” resemblance.


Elodea: Elodea is a rooted multi-branched plant with dark green blade-like leaves are in whorls of three with finely toothed margins. The flowers of Elodea have three white petals with a waxy coating that makes them float.

Floating Pondweeds: There are several different varieties of floating pondweeds (American, Illinois, and Variable Leaf, among others).  They can be distinguished by having both floating and submerged leaves. The floating leaves are usually elliptical in shape on long petioles. Submerged leaves are not abundant and are blade-like and smaller than floating leaves. Fruits often are on spikes that often stand above the water’s surface and are brownish to reddish or green.

Hydrilla: Hydrilla forms dense branching colonies which after reaching the surface extend across it forming thick mats. Leaves are blade-like with small tooth margins and spines on the underside of the midrib which make them feel rough. Leaves are usually 4 to 8 in a whorl.  Hydrilla can form mats on the water’s surface in water up to 20 feet deep.

Naiads: There are many different varieties of Naiads (Brittle, Marine and Spiny, among others).  For the most part they are all rooted submerged plants with smaller green leaves (½” to 1 ½” long) that can be highly toothed.  Flowers are typically smaller and at the base of the leaves and they often can only be observed with magnification.

Submerged Pondweeds: There are many different varieties of submerged pondweeds (Sago, Baby and Curly-leaf, among others).  All are characterized by having very thin leaves that can grow very long but come to a tapering point, with thin stems that are long and highly branching.  One variety, Curly-leafed pondweed, has rippled or wavy submerged leaves.

Vallisneria: Vallisneria is also called Eelgrass, for its long, thin ribbon like leaves that can grow up to 3 or 4 feet and ½ to ¾ inches wide.  It is often found in flowing water.

Water Milfoil: Water Milfoil has stems are multi-branched, somewhat reddish in color, with gray-greenish feather-like leaves. The leaves are in whorls of 3 to 5 around the stem with each leaf divided into 12 or more pairs of thin thread-like leaflets that look like small feathers.


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