Aquatic Plant Identification

NATIVE:  Common bladderwort will usually be found free floating as it has no visible roots.  It has floating stems with leaf-like branches that fork 3-7 times.  Scattered on these branches are bladders that trap young prey.  Young bladders are transparent and green tinted, but they become dark brown to black as they age.  Common bladderwort will also produce yellow flowers that protrude above the water surface.

NATIVE:  Bushy pondweed has fine branched stems that emerge from a thin rootstalk.  Leaves are narrow with a broad base where they attach to the stem.  Edges of the leaf will be finely serrated.  Tiny flowers and seeds can develop in the leaf axils.

NATIVE:  This unusual type of algae resembles a higher plant without true roots.  Main branches are often encrusted by calcium carbonate, giving it a harsh, crusty feel.  Chara is typically low growing   and can be identified by its musky odor.

NATIVE:  Clasping-leaf pondweed has oval to somewhat lance-shaped leaves that "clasp" around one-half to three-quarters of the stem circumference.  Leaves have 13-21 veins and white fibers are typically found at the leaf node.  No floating leaves are produced.  Fruiting stalks develop with cylindrical spikes that are packed with seeds.  Each seed is plump and round with a prominant beak.

NATIVE:  Coontail has long, trailing stems that lack true roots though the plant may be loosely anchored.  Leaves are stiff and arranged in whorls of 5-12.  Each leaf is forked once or twice and the leaf divisions have teeth along the margins that are tipped with a small spine.  Leaves are usually more closely spaced near the ends of branches, creating the raccoon tail appearance.

EXOTIC:  Curly-leaf has leaves that are oblong and are attached directly to the stem in an alternating pattern.  Margins of the leaves are wavy, finely serrated, and typically resemble lasagna noodles.  Curly-leaf produces small pinecone like seeds called turions that can lay dormant in a water body for 5-7 years making it very hard to eradicate.

NATIVE:  Duckweed has round to oval-shaped leaf bodies called fronds that float individually or in groups on the water surface.  Each frond has three faint nerves, one root and no stems.  Duckweed is usually found in ponds protected from the wind where wave action in minimal.

NATIVE:  Elodea has slender stems that emerge from a shallow rootstalk.  The small lance-shaped leaves attach directly to the stem.  Leaves are in whorls of three, or occasionally only two and tend to be more crowded toward the stem tips.  Elodea typically stays low growing to the bottom but can become problematic in shallow waters.

EXOTIC:  EWM has long spaghetti-like stems sometimes 2 or more meters in length.  Leaves are divided like a feather with 14-20 pairs of leaflets.  Leaves are in whorls of 4-5 and can be widely spaced.  EWM can reproduce from fruiting bodies   and from fragmentation making it hard to control   once established.

NATIVE:  The stems are strongly flattened and have an angled appearance.  Stiff linear leaves have a prominent midvein and many fine, parallel veins.  Flat-stem does not have any floating leaves except for its nutlike fruits that are arranged in a cylindrical spike that pokes out of the water. 

NATIVE:  Floating-leaf pondweed has stems that emerge from red-spotted rhizomes.  Submersed leaves are stalk-like, with no obvious leaf blade.  Floating leaves are heart-shaped at their base.  The point where the floating leaf attaches to the stalk is distinctive.  It looks like someone pinched the stalk   and bent it, so the leaf blade is at a right angle to the stalk and lays flat on the water.  Flowers and fruit are produced in a dense cylindrical spike that pokes above the water surface.  Fruit is oval to egg-shaped and plump with a wrinkled appearance on the sides and a short beak.

NATIVE:  Forked Duckweed has a simple, flattened leaf body or frond that is long stalked with three faint nerves and a single root.  Lateral fronds often remain attached to the parent frond, creating a "rowboat and oars" shape.  Flowers are seldom produced and can only be seen with magnification.  Forked Duckweed is often found just under the water surface, seldom making it a nuisance.

EXOTIC:  Phragmites have stems 2-4 meters tall that grow out of stout rhizomes.  Some of the stems are topped with spreading clusters of spikelets.  Each spikelet has 3-7 florets and long silky hairs that give a feather duster appearance.  It grows along shorelines and in a variety of wetlands.

NATIVE:  Horned Pondweed has long, linear, thread-like leaves that are mostly opposite or arranged in whorls on slender branching stems.  Leaf tips gradually taper to a point, and a thin sheath or stipule covers the basal parts of leaves.  Horned pondweed gets its name from it's seeds that occur in groups of 2-4 and are horned shaped. 

EXOTIC:  Hydrilla has a long stem that is branched with oppositely arranged leaves at the bottom.  It has whorls of three to eight leaves with the leaf having an oval shape with toothed margins.  Hydrilla can reproduce from fragmentation making it hard to  control once established.  Hydrilla has been rarely found in Wisconsin and should be reported to the   DNR if seen.

NATIVE:  Illinois Pondweed has stout stems that emerge from a thick rhizome.  Most of the submerged leaves are lanced shaped to oval and either attached directly to the stem or have a short stalk.  The leaves have 9-19 veins and often have a sharp needle like tip.  The stipules are free in the axils of the leaves and have two prominent ridges called keels.

NATIVE:  Large-leaf Pondweed has the broadest leaf (3.5-7 cm wide) of any pondweed in our region.   These leaves are arched and slightly folded.  The   leaf varies in length and is lined with many veins (25-37).  Large-leaf Pondweed has larger leaves than Illinois Pondweed and has more veins throughout the leaf.

NATIVE:  Leafy pondweed has freely branched stems that emerge from slender rhizomes.  The narrow, submersed leaves have parallel sides that narrow slightly where they attach to the stem.  The tip of the leaf usually tapers to a point.  No floating leaves are produced.  Flowers and fruit are produced on short stalks in the axils of the upper leaves.  Fruits are in tight clusters and are flattened with a wavy ridge and a short beak.

NATIVE:  NWM has stems that are sparingly branched and fairly erect in the water.  The leaves are divided like a feather and have 5-12 pairs of thread-like leaflets.  The lower leaflet pairs are longer than the upper ones, creating a Christmas tree shape.  The leaves are arranged in whorls with 4-5 leaves per whorl.

EXOTIC:  Parrot Feather has long unbranched stems emerging from roots and rhizomes.  These stems can grow to a height of 6" above the water surface.  Slender, feather-like leaves occur in whorls of 4 to 6 leaves.  Whorls are openly spaced toward the base, and more closely arranged toward the growing tip.  Each leaf will have 10 - 18 leaflet pairs.  Emmergent leaves are robust, vibrant green, and covered with a waxy coating.  Small white flowers can be found on femail plants in the axils of emmergent leaves.  Report any infestations to the DNR.

EXOTIC:  Purple Loosestrife has angled stems that emerge from a woody rootstalk.  Leaves are lance shaped, attached directly to the stem, and often have fine hairs on the surface.  Clusters of magenta flowers are produced in leaf axils of a terminal spike.  Each flower has 5-7 narrow petals that are wrinkled with a tissue paper consistency.  It is typically found in moist soils and shallow water.

EXOTIC:  Just recently found in Wisconsin, Sacred Lotus produces individual leaves and flowers directly from the root system with thick rhizomes.  The blades of the leaves either float on the surface of the water  or are held up to 6' above the water by their petioles.  Leaf margins are smooth and undulate up and down.  Individual flowers are also held up to 6' above the water.  They are 4-8" across and consist of about 15 pink petals, a golden receptacle, and dense ring of golden stamens.  Short-lived flowers open during the morning and begin to lose petals in the afternoon.  Flowers are replaced by a seed pod that becomes dark brown and eventually bend downward to release seeds into the water.  Sacred Lotus spreads by its rhizomes or seeds which have been documented to remain viable for over 1200 years!  Please report new infestations to the DNR.

NATIVE:  The stems of Sago Pondweed sprout from slender rhizomes that are peppered with starchy tubers.  The leaves are very thin and resemble pine needles, ending in a sharp point.  Each branch may be forked several times into a spreading, fan-like arrangement.  Flowers and fruits are produced on a slender stalk that may be submersed or floating on the water surface.

NATIVE:   Small pondweed has slender stems that emerge from a slight rhizome and branch repeatedly near the ends.  Submersed leaves are linear and attach directly to the stem.  The leaves have three veins and the mid-vein may be bordered by several rows of hollow cells.  No floating leaves are produced.  The flowers and fruits are produced in 1-4 whorls on   a slender stalk.  The oval fruit is rather plump and has a smooth back and short beak.

NATIVE:   There are two white-flowered and one yellow flowered water buttercup species common in our region.  Water buttercup has long, branched stems that emerge from both trailing runners and buried rhizomes.  The leaves are finely cut into thread-like divisions (white) or flattened divisions (yellow) and either attach directly to the stem or have a very short leaf stalk.  Leaves emerge along the stem in an alternate arrangement and are usually stiff enough to hold their shape when lifted out of the water.  White or yellow, five-petaled flowers are produced on stalks just above the water surface.  As flowers develop into fruit, the stalks curve back into the water and a cluster of 15-25 nutlets is produced.

NATIVE:   Wild Celery has ribbon-like leaves that emerge in clusters along a creeping rhizome.  The leaves have a prominant central stripe and cellophane-like consistency.  The leaves are mostly submersed, with just the tips trailing on the surface of the water.  Male and female flowers are produced on separate plants though they are very small (1 - 6.5 mm wide).

EXOTIC:  Water Hyacinth has leaves that are large and broadly lance-like extending from an inflated stalk.  Flowers are blue, violet, or white.  The roots are dark and fibrous.  The height of the plant ranges from a few inches to three feet tall.  Water Hyacinth can reproduce from seeds or by fragmentation making it difficult to control.  If found in a water body it should be reported to the DNR.

NATIVE:  Watermeal is composed of pale green, asymmetrical globes with no roots, stems, or true leaves.  Watermeal has the distinction   of being one of the world's smallest flowering plants, however the flowers can only be seen under magnification and are seldom present.  It typically grows in areas that are  not disturbed by wind and wave action.

NATIVE:  White water lily has a cylindrical leaf attached to a round stalk.  The flowers float on the waters surface and are borne on individual flower stalks that rise directly from the rhizome.  They have four greenish sepals and numerous white petals in a circular arrangement. 

NATIVE:  The trailing stems of widgeon grass emerge from a shallow root system.  Stiff, slender leaves are scattered on the stems.  Each leaf has an expanded open sheath at the base.  The flower stalk is long and spirally twisted.  As the flowers mature, the fruit is elevated on stalks in an umbrella-like cluster.

EXOTIC:  If Yellow Floating Heart is found in your water body please contact the DNR.  Just recently found in Wisconsin, Yellow Floating Heart can be very hard to eradicate once established.  Identified by its "heart-like" shape, yellow flowers, and wavy purple edges, it is smaller than spatterdock rarely reaching sizes larger than your hand.

NATIVE:  Spatterdock has a sturdy leaf stalk that has a flattened upper surface with a narrow wing running down each side.  Leaves of spatterdock are heart shaped with rounded lobes that are parallel or overlapping.  Flowers are globular to saucer shaped with 5-6 yellow sepals that often have a deep red patch at the base.