Some Common Algae and Aquatic Weeds of Canada and U.S. Basic Identification and Information Guide Revision Date: November 1, 2004 START MENU

Some Common Algae and Aquatic Weeds of Canada and U.S.

Basic Identification and Information GuideBasic Identification and Information Guide

Revision Date: November 1, 2004Revision Date: November 1, 2004

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Nitella spp.Chara spp.Filamentous or Planktonic

Algae can be generally categorized by the form it takes in water (ex. planktonic, filamentous, erect), or by algal groups (ex. green algae, blue-green algae etc.)

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Planktonic and Filamentous AlgaePlanktonic and Filamentous Algae

PlanktonicPlanktonic algae are floating microscope algae are floating microscope plants that are normal and essential plants that are normal and essential inhabitants of sunlit surface waters. There inhabitants of sunlit surface waters. There are literally millions of floating planktonic are literally millions of floating planktonic algae that turn pond water shades of green, algae that turn pond water shades of green, blue-green, brown or variations in between. blue-green, brown or variations in between. Planktonic algae that colors the water is often Planktonic algae that colors the water is often called a “bloom” or “algae bloom”. Many called a “bloom” or “algae bloom”. Many species of planktonic algae can be present at species of planktonic algae can be present at the same time in a water bodythe same time in a water body11. .

FilamentousFilamentous algae are single algae cells that algae are single algae cells that form long visible chains, threads, or filaments. form long visible chains, threads, or filaments. These filaments intertwine forming a mat that These filaments intertwine forming a mat that resembles wet wool. Filamentous algae starts resembles wet wool. Filamentous algae starts growing along the bottom in shallow water or growing along the bottom in shallow water or attached to structures in the water (like rocks or attached to structures in the water (like rocks or other aquatic plants). Often filamentous algae other aquatic plants). Often filamentous algae floats to the surface forming large mats, which floats to the surface forming large mats, which are commonly referred to as “pond scums”. are commonly referred to as “pond scums”. There are many species of filamentous algae There are many species of filamentous algae and often more than one species will be and often more than one species will be present at the same timepresent at the same time11..

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Some common Some common types of planktonic types of planktonic algae include: algae include: Chlamydomonas, Chlamydomonas, Chlorella, Chlorella, Euglena,Closterium, Euglena,Closterium, Anacystis spp., etc.Anacystis spp., etc.

Some common Some common types of filamentous types of filamentous algae include: algae include: Spirogyra, Spirogyra, Anabaena, Anabaena, Oscillatoria, Oscillatoria, Lyngbya, Pithophora Lyngbya, Pithophora spp., etcspp., etc

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Green Algae:Green Algae: a very large and diverse group of algae (mostly freshwater). Typically a very large and diverse group of algae (mostly freshwater). Typically green, but not always. During a bloom, water generally looks greenish in colour. green, but not always. During a bloom, water generally looks greenish in colour. Some are motile, while others are sessile. Some common Green Algae are shown Some are motile, while others are sessile. Some common Green Algae are shown belowbelow66::

Blue-Green Algae (Cyanobacteria):Blue-Green Algae (Cyanobacteria): Used to be considered algae, but is actually more Used to be considered algae, but is actually more closely related to bacteria. A cyanobacteria bloom is obvious when the water turns a closely related to bacteria. A cyanobacteria bloom is obvious when the water turns a blue-green colour. Some common Cyanobacteria are shown belowblue-green colour. Some common Cyanobacteria are shown below66::

Different Algae GroupsDifferent Algae Groups

Planktonic forms Filamentous forms

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Diatoms:Diatoms: Usually yellow-brown in colour, with rigid looking cell walls. Diatoms are Usually yellow-brown in colour, with rigid looking cell walls. Diatoms are usually sessile and can be numerous in fresh water. Some common diatoms are usually sessile and can be numerous in fresh water. Some common diatoms are shown belowshown below66::

Red AlgaeRed Algae:: Not very common in fresh water, and not always red. Most Red Algae is Not very common in fresh water, and not always red. Most Red Algae is marine. Often during a bloom, water will appear brown or reddish. Some common marine. Often during a bloom, water will appear brown or reddish. Some common Red Algae are shown belowRed Algae are shown below66::

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Desmids:Desmids: Fairly common freshwater algae. Many have 2 semi cells that are mirror Fairly common freshwater algae. Many have 2 semi cells that are mirror images. Some of the very large desmids can be seen without magnification. Some images. Some of the very large desmids can be seen without magnification. Some common desmids are shown belowcommon desmids are shown below66::

Please click on the link below, then click on Please click on the link below, then click on ALGAEALGAE on the webpage for on the webpage for further algae informationfurther algae information

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Chara spp.Chara spp.

Chara is often called muskgrass or skunkweed because of its foul, musty almost Chara is often called muskgrass or skunkweed because of its foul, musty almost garlic-like odor. Chara is a gray-green branched multicellular algae that is often garlic-like odor. Chara is a gray-green branched multicellular algae that is often confused with submerged flowering plants. However, Chara has no flower, will not confused with submerged flowering plants. However, Chara has no flower, will not extend above the water surface, and often has a “grainy” or “crunchy” texture. extend above the water surface, and often has a “grainy” or “crunchy” texture. Chara has cylindrical, whorled branches with 6 to 16 branchlets around each Chara has cylindrical, whorled branches with 6 to 16 branchlets around each nodenode11. .

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Distribution:

Worldwide

Nitella spp.Nitella spp.

A special kind of algae that grows only in fresh water is Nitella (also known as A special kind of algae that grows only in fresh water is Nitella (also known as stoneworts). They resemble small tress and grow in miniature forests at the stoneworts). They resemble small tress and grow in miniature forests at the lake bottom; they are known for their unpleasant smell. Nitella is branched lake bottom; they are known for their unpleasant smell. Nitella is branched multicellular algae that is often confused with submerged flowering plants. multicellular algae that is often confused with submerged flowering plants. However, it has no flower and will not extend above the water surface. Nitella However, it has no flower and will not extend above the water surface. Nitella has no odor and is soft to the touch, unlike Chara. Stoneworts are light to dark has no odor and is soft to the touch, unlike Chara. Stoneworts are light to dark green in color with forked, bushy branches 1/16 to 1/8 inches in diametergreen in color with forked, bushy branches 1/16 to 1/8 inches in diameter11. .

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Distribution:

Worldwide

Aquatic PlantsAquatic Plants

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Floating Submersed Emergent

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Floating Aquatic PlantsFloating Aquatic Plants

Duckweed Watermeal Watershield

Water Hyacinth White Water Lily Yellow Water Lily

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Common Duckweed is a very small light green free-floating, seed bearing plant. Common Duckweed is a very small light green free-floating, seed bearing plant. Duckweed has 1 to 3 leaves - 1/16 – 1/8 inch in length. A single root hair protrudes Duckweed has 1 to 3 leaves - 1/16 – 1/8 inch in length. A single root hair protrudes from each tiny leaf. Giant or big duckweed is still relatively small 1/16 to 1/4 inch with from each tiny leaf. Giant or big duckweed is still relatively small 1/16 to 1/4 inch with 1 to 4 leaves with three or more roots hairs protruding from each leaf. Duckweeds 1 to 4 leaves with three or more roots hairs protruding from each leaf. Duckweeds tend to grow in dense colonies in undisturbed waters or ponds, and can be tend to grow in dense colonies in undisturbed waters or ponds, and can be aggressive invaders of ponds. These plants should be controlled before they cover aggressive invaders of ponds. These plants should be controlled before they cover the entire surface of the pondthe entire surface of the pond11..

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Distribution:

Worldwide

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Duckweed – Lemna spp., Spirodela spp.Duckweed – Lemna spp., Spirodela spp.

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Watermeal - Watermeal - Wolfia spp.Wolfia spp.

Watermeal is a very tiny (<1mm) light green Watermeal is a very tiny (<1mm) light green free-floating, rootless plant. Watermeal tends to free-floating, rootless plant. Watermeal tends to grow in dense colonies in undisturbed water. grow in dense colonies in undisturbed water. Often watermeal will be associated with Often watermeal will be associated with colonies of duckweeds. Watermeal can be an colonies of duckweeds. Watermeal can be an aggressive invader of ponds and are often aggressive invader of ponds and are often found mixed in with duckweeds and other found mixed in with duckweeds and other aquatic plants. If colonies cover the surface of aquatic plants. If colonies cover the surface of the water, then oxygen depletions and fish kills the water, then oxygen depletions and fish kills can occur. These plants should be controlled can occur. These plants should be controlled before they cover the entire surface of the before they cover the entire surface of the pondpond11. .

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Distribution:

Worldwide


Watershield - Watershield - Brasenia spp.Brasenia spp.

Watershield is an aquatic floating perennial. Leaves are alternate, floating, oval to Watershield is an aquatic floating perennial. Leaves are alternate, floating, oval to elliptic in outline, and approximately 4 1/2 inches long and 2 1/2 inches wide. elliptic in outline, and approximately 4 1/2 inches long and 2 1/2 inches wide. Leaves are green and shiny on the upper surface and purple on the lower Leaves are green and shiny on the upper surface and purple on the lower surface. The undersides of the leaves are covered with a thick, jelly-like surface. The undersides of the leaves are covered with a thick, jelly-like substance. The leaves occur on petioles that range from 4 to 12 inches in length. substance. The leaves occur on petioles that range from 4 to 12 inches in length. Stems are branched and may reach 6 feet in length. Primarily a weed of poorly-Stems are branched and may reach 6 feet in length. Primarily a weed of poorly-managed lakes or ponds that most commonly occurs in water up to about 5 feet managed lakes or ponds that most commonly occurs in water up to about 5 feet deepdeep44. .

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Distribution: Throughout most of US to Southern Canada


Water Hyacinth – Water Hyacinth – Eichhoria crassipesEichhoria crassipes

Water Hyacinth is a free-floating perennial plant that can grow to a height of 3 feet. Water Hyacinth is a free-floating perennial plant that can grow to a height of 3 feet. The dark green leave blades are circular to elliptical in shape attached to a The dark green leave blades are circular to elliptical in shape attached to a spongy, inflated petiole. Underneath the water is a thick, heavily branched, dark spongy, inflated petiole. Underneath the water is a thick, heavily branched, dark fibrous root system. The water hyacinth has striking light blue to violet flowers fibrous root system. The water hyacinth has striking light blue to violet flowers located on a terminal spike. Water hyacinth is a very aggressive invader and can located on a terminal spike. Water hyacinth is a very aggressive invader and can form thick mats. If these mats cover the entire surface of the pond they can cause form thick mats. If these mats cover the entire surface of the pond they can cause oxygen depletions and fish kills. Water hyacinths should be controlled so they do oxygen depletions and fish kills. Water hyacinths should be controlled so they do not cover the entire pondnot cover the entire pond11. .

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Distribution:

Southern US


White Water Lily – White Water Lily – Nymphaea spp.Nymphaea spp.

The White Water Lily is a perennial plant that often forms dense colonies. The leaves The White Water Lily is a perennial plant that often forms dense colonies. The leaves arise on flexible stalks from large thick rhizomes. The leaves are round, bright green, 6 arise on flexible stalks from large thick rhizomes. The leaves are round, bright green, 6 to 12 inches in diameter with the slit about 1/3 the length of the leaf. Leaves usually to 12 inches in diameter with the slit about 1/3 the length of the leaf. Leaves usually float on the water's surface. Flowers arise on separate stalks, have brilliant white float on the water's surface. Flowers arise on separate stalks, have brilliant white petals (25 or more per flower) with yellow centers. The flowers may float or stick above petals (25 or more per flower) with yellow centers. The flowers may float or stick above the water and each opens in the morning and closes in the afternoon. White water lily the water and each opens in the morning and closes in the afternoon. White water lily can spread from seeds or the rhizomescan spread from seeds or the rhizomes11. .

Distribution:

Throughout North

America

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Yellow Water Lily – Yellow Water Lily – Nuphar spp.Nuphar spp.

Yellow Water Lilies are Yellow Water Lilies are perennial plants that arise on perennial plants that arise on flexible stalks from rhizomes flexible stalks from rhizomes and large fleshy roots that can and large fleshy roots that can resemble bananas. Leaves resemble bananas. Leaves are oval heart-shape, 3 to 6 are oval heart-shape, 3 to 6 inches in diameter, shiny dark inches in diameter, shiny dark green on top and reddish-green on top and reddish-purple underneath Leaves purple underneath Leaves float on the surface and are float on the surface and are seldom emergent. Flowers are seldom emergent. Flowers are large (2 1/2 to 4 inches) bright large (2 1/2 to 4 inches) bright yellow and usually stand above yellow and usually stand above the water on separate stalks. the water on separate stalks. Yellow water lilies can Yellow water lilies can reproduce from seeds or by reproduce from seeds or by spreading of the rhizomesspreading of the rhizomes11. .

Distribution:

Throughout North America


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Submersed Aquatic PlantsSubmersed Aquatic Plants

Bladderwort Coontail Curly-leaf Pondweed

Elodea

Eurasian Watermilfoil

Richardson Pondweed

Sago Pondweed

Tapegrass



Bladderwort – Bladderwort – Utricularia vulgarisUtricularia vulgaris

Bladderwort is a submersed aquatic Bladderwort is a submersed aquatic plant that floats freely throughout plant that floats freely throughout the water and have no true roots. the water and have no true roots. The bladders that occur on the The bladders that occur on the stems and leaves of all the stems and leaves of all the UtriculariaUtricularia species helps to species helps to distinguish these weeds from any distinguish these weeds from any other floating or submerged aquatic other floating or submerged aquatic weedsweeds44..

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Distribution:

Throughout Northern

Hemisphere

Coontail – Coontail – Ceratophyllum demersumCeratophyllum demersum

Coontail (sometimes called hornwort) Coontail (sometimes called hornwort) is a dark olive-green, rootless is a dark olive-green, rootless submerged perennial plant that often submerged perennial plant that often forms dense colonies. Leaves are forms dense colonies. Leaves are relatively stiff, whorled with many relatively stiff, whorled with many forks and small teeth along one edge. forks and small teeth along one edge. The tips of branches are crowded The tips of branches are crowded with leaves giving it a “coontail” with leaves giving it a “coontail” resemblance. Coontail reproduces by resemblance. Coontail reproduces by seeds and fragmentationseeds and fragmentation11. .


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Distribution:

Worldwide

Curly-leaf Pondweed – Curly-leaf Pondweed – Potamogeton crispusPotamogeton crispus

Curly-leafed pondweed is a perennial Curly-leafed pondweed is a perennial plant that is native to Europe and gets plant that is native to Europe and gets it name from the rippled or wavy it name from the rippled or wavy nature of its submerged leaves. The nature of its submerged leaves. The leaves are 3/4 to 4 inches long and ¼ leaves are 3/4 to 4 inches long and ¼ to ½ inch wide. Mature leaves are to ½ inch wide. Mature leaves are toothed with a distinct midrib with toothed with a distinct midrib with paired parallel lateral veins, nearly paired parallel lateral veins, nearly translucent. Fruits are seldom found. translucent. Fruits are seldom found. There are small “bur” like reproductive There are small “bur” like reproductive structures at the base of some leaves. structures at the base of some leaves. Curly-leafed pondweed can be an Curly-leafed pondweed can be an aggressive invader that can cover aggressive invader that can cover large portions of pondslarge portions of ponds11. .

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Distribution:

Nearly Worldwide

Elodea - Elodea - Egeria spp.Egeria spp.

Brazilian elodea (Egeria) looks very Brazilian elodea (Egeria) looks very much like a larger, more robust version much like a larger, more robust version of its commonly-found native relative, of its commonly-found native relative, Elodea canadensisElodea canadensis (Canada (Canada Waterweed)Waterweed)55. Egeria is native to South . Egeria is native to South America but has become naturalized in America but has become naturalized in much of the Southeastern U.S. The much of the Southeastern U.S. The dark green lance-like leaves are in dark green lance-like leaves are in whorls of 4 to 6 which become more whorls of 4 to 6 which become more dense near the tip of the stem (near the dense near the tip of the stem (near the surface). Leaves are about ½ inch wide surface). Leaves are about ½ inch wide and from ¾ to 1 ¼ inches long with and from ¾ to 1 ¼ inches long with finely toothed margins. Flowers are finely toothed margins. Flowers are white about 3/8 to ¾ inches in diameter white about 3/8 to ¾ inches in diameter on short stalks which commonly are on short stalks which commonly are emergent. Egeria is often confused with emergent. Egeria is often confused with the native Elodea or the non-native the native Elodea or the non-native Hydrilla. Hydrilla has one or more teeth Hydrilla. Hydrilla has one or more teeth on the underside of the midrib, neither on the underside of the midrib, neither Elodea nor Egeria have these midrib Elodea nor Egeria have these midrib teeth. The teeth make Hydrilla feel teeth. The teeth make Hydrilla feel rough when drawn through your hand rough when drawn through your hand from base to tipfrom base to tip11. .

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Distribution:

Areas of North America

Eurasian Watermilfoil – Eurasian Watermilfoil – Myriophyllum spicatumMyriophyllum spicatum

Eurasian Watermilfoil is considered Eurasian Watermilfoil is considered one of the most aggressive and one of the most aggressive and problematic plants in North America problematic plants in North America because of the dense colonies which it because of the dense colonies which it forms. The stems are multi-branched, forms. The stems are multi-branched, somewhat reddish in color, with gray-somewhat reddish in color, with gray-greenish feather-like leaves. The greenish feather-like leaves. The leaves are in whorls of 3 to 5 around leaves are in whorls of 3 to 5 around the stem with each leaf divided into 12 the stem with each leaf divided into 12 or more pairs of thin thread-like or more pairs of thin thread-like leaflets. Reddish flowers are borne on leaflets. Reddish flowers are borne on leafless spikes that rise above the leafless spikes that rise above the surface a few inches. Eurasian surface a few inches. Eurasian watermilfoil is non-native and should watermilfoil is non-native and should not be spreadnot be spread11. .

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Distribution:

Widespread in North America

Richardson Pondweed – Richardson Pondweed – Potamogeton richardsoniiPotamogeton richardsonii

Richardson Pondweed has densely spaced, lance shaped leaves, 2-13 cm long, 1-3 Richardson Pondweed has densely spaced, lance shaped leaves, 2-13 cm long, 1-3 cm wide, and have wavy often curved backwards margins. Stem often branched to 1 cm wide, and have wavy often curved backwards margins. Stem often branched to 1 m long. Flowers in 4-12 whorls on short spikes. Flower stalks generally just longer m long. Flowers in 4-12 whorls on short spikes. Flower stalks generally just longer than the spike, but sometimes much longerthan the spike, but sometimes much longer1111..

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Distribution:

Widespread throughout

North America


Sago Pondweed – Sago Pondweed – Potamogeton pectinatusPotamogeton pectinatus

Sago pondweed is a perennial plant Sago pondweed is a perennial plant that has no floating leaves. The stems that has no floating leaves. The stems are thin, long and highly branching are thin, long and highly branching with leaves very thin and filament-like, with leaves very thin and filament-like, about 1/16 of an inch wide and 2 to about 1/16 of an inch wide and 2 to over 12 inches long tapering to a over 12 inches long tapering to a point. The fruit is nut-like 1/8 to 1/4 point. The fruit is nut-like 1/8 to 1/4 inches long and 1/10 to 1/8 inches inches long and 1/10 to 1/8 inches widewide11. .

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Distribution:

Worldwide

Tapegrass - Tapegrass - Vallisneria americanaVallisneria americana

Tapegrass, Eelgrass, or Wild Celery are all Tapegrass, Eelgrass, or Wild Celery are all common names for common names for VallisneriaVallisneria. Tapegrass is . Tapegrass is a rooted submerged plant often found in a rooted submerged plant often found in flowing water. It has long, thin, ribbon-like flowing water. It has long, thin, ribbon-like leaves (1/2 – ¾ inches wide) that are leaves (1/2 – ¾ inches wide) that are commonly 3 to 4 feet long. The vein pattern commonly 3 to 4 feet long. The vein pattern in the leaves of eelgrass is very distinctive in the leaves of eelgrass is very distinctive and resembles celery. Tapegrass has a vast and resembles celery. Tapegrass has a vast rhizome system that allows it to form dense rhizome system that allows it to form dense colonies and usually excludes other colonies and usually excludes other submerged plantssubmerged plants11. .

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Distribution:

Throughout most of North

America


Emergent Aquatic PlantsEmergent Aquatic Plants



Arrowhead Bulrush Cattail Fanwort

Horsetail Pickerelweed Purple Loosestrife Sedges

Smartweed Water Plantain Water Stargrass White Water Buttercup

Arrowhead – Arrowhead – Sagittaria spp.Sagittaria spp.

There are many species of There are many species of SagittariaSagittaria but all are perennial but all are perennial plants that have arrowhead-shaped plants that have arrowhead-shaped leaves. Usually leaves have 3 leaves. Usually leaves have 3 points giving it the arrowhead points giving it the arrowhead shape but some are narrow and shape but some are narrow and almost grass-like. Arrowheads can almost grass-like. Arrowheads can grow in shallow water or in wet grow in shallow water or in wet areas. Leaves grow in clusters areas. Leaves grow in clusters from the base and can be from less from the base and can be from less than a foot tall to over 4 feet. Leaf than a foot tall to over 4 feet. Leaf petioles are long, often spongy and petioles are long, often spongy and have a milky-like fluid if crushed. have a milky-like fluid if crushed. Rhizomes can be extensive and Rhizomes can be extensive and some species have large tubers off some species have large tubers off the roots. Flowers are borne on the roots. Flowers are borne on separate stalks above the water in separate stalks above the water in whorls of three and are usually whorls of three and are usually white to light pink with three petals. white to light pink with three petals. Arrowheads spread rapidly by Arrowheads spread rapidly by seeds and extensive rhizomesseeds and extensive rhizomes11. .

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Distribution:

Southern Canada and US

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Bulrush - Scirpus spp.Bulrush - Scirpus spp.

There are several species of bulrushes. Bulrushes are perennial grass-like There are several species of bulrushes. Bulrushes are perennial grass-like plants and can grow to 10 feet tall in shallow water or in moist soils. Soft-stem plants and can grow to 10 feet tall in shallow water or in moist soils. Soft-stem bulrush can grow to 10 feet and grows in dense colonies from rhizomes. Soft-bulrush can grow to 10 feet and grows in dense colonies from rhizomes. Soft-stem bulrush has a round (in cross section), light gray-green, relatively soft stem bulrush has a round (in cross section), light gray-green, relatively soft stem that comes to a point with no obvious leaves (only sheaths at the base of stem that comes to a point with no obvious leaves (only sheaths at the base of the stems). Flowers usually occur just below the tip of the stemthe stems). Flowers usually occur just below the tip of the stem11..

Giant bulrush can also grow to 10 feet, is dark green with a hard, triangular Giant bulrush can also grow to 10 feet, is dark green with a hard, triangular stem and no obvious leaves (sheaths at the base of the stems)stem and no obvious leaves (sheaths at the base of the stems)11..

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Distribution:

North America to Worldwide


Cattail - Cattail - Typha spp.Typha spp.

Cattails have flat to slightly rounded Cattails have flat to slightly rounded leaves that twist slightly over their leaves that twist slightly over their length and can grow to 5 or 10 feet in length and can grow to 5 or 10 feet in height. Flowers form a dense dark height. Flowers form a dense dark brown, cigar-shaped at the end of brown, cigar-shaped at the end of spikes (called the catkin). Cattails can spikes (called the catkin). Cattails can be partially submerged or in boggy be partially submerged or in boggy areas with no permanently standing areas with no permanently standing water. Cattails spread rapidly because water. Cattails spread rapidly because their seeds blow in the wind and float their seeds blow in the wind and float on the water's surface and vegetatively on the water's surface and vegetatively they spread from underground they spread from underground rhizomesrhizomes11. .

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Distribution:

Worldwide

Fanwort –Fanwort – Cabomba carolinianaCabomba caroliniana

Fanwort is a rooted submersed plant. Fanwort is a rooted submersed plant. It may have submersed and floating It may have submersed and floating leaves of different shapes. Fanwort leaves of different shapes. Fanwort generally grows in 3-10 ft of water, and generally grows in 3-10 ft of water, and is found in ponds, lakes and quiet is found in ponds, lakes and quiet streams. Fanwort stems are long and streams. Fanwort stems are long and much-branched. Fanwort has fan-like much-branched. Fanwort has fan-like underwater leaves, which are about underwater leaves, which are about two inches across. The submersed two inches across. The submersed leaves are frequently divided, and are leaves are frequently divided, and are arranged oppositely or in whorls along arranged oppositely or in whorls along the stem. The floating leaves are the stem. The floating leaves are small, diamond-shaped, and are small, diamond-shaped, and are infrequent. Fanwort flowers are white infrequent. Fanwort flowers are white to pink to purplish and are about 1/2 to pink to purplish and are about 1/2 inch across. The flowers are on stalks inch across. The flowers are on stalks which arise from the tips of the which arise from the tips of the stemsstems1010. .

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Distribution:

Mostly Eastern US


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Horsetail – Horsetail – Equisetum hyemaleEquisetum hyemale

Horsetail is a perennial plant with dark-Horsetail is a perennial plant with dark-green hollow, jointed or segmented green hollow, jointed or segmented stems 1/4 to 1/2 inch tick with no true stems 1/4 to 1/2 inch tick with no true leaves. Stems may be singular or leaves. Stems may be singular or have whorls of branches. Only single have whorls of branches. Only single stems produce the cone-shaped spore stems produce the cone-shaped spore producing body at the tip. Horsetails producing body at the tip. Horsetails can be standing in water or in wet can be standing in water or in wet areas. Horsetail stems contain silicon areas. Horsetail stems contain silicon crystals (i.e. sand) embedded in its crystals (i.e. sand) embedded in its tissue. This gritty texture gives it a tissue. This gritty texture gives it a common name of "scouring rush“common name of "scouring rush“11. .


Distribution:

Northern Hemisphere

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Pickerelweed – Pontederia spp.Pickerelweed – Pontederia spp.

Pickerelweed is a perennial plant that Pickerelweed is a perennial plant that can grow up to 3 1/2 feet tall. Leaves can grow up to 3 1/2 feet tall. Leaves are shiny green, heart-to-lance are shiny green, heart-to-lance shaped(up to 7 inches long) singly shaped(up to 7 inches long) singly attached to a long petiole which grow attached to a long petiole which grow in a rosette from the roots. Each stem in a rosette from the roots. Each stem can produce a terminal flower spike 3 can produce a terminal flower spike 3 to 4 inches long. The numerous to 4 inches long. The numerous tubular flowers on the spike are violet-tubular flowers on the spike are violet-blue in color. Each flower lasts only blue in color. Each flower lasts only one day. Pickerelweed reproduces one day. Pickerelweed reproduces from seeds and rhizomesfrom seeds and rhizomes11. .


Distribution:

Temperate North and South America

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Purple Loosestrife - Purple Loosestrife - Lythrum salicariaLythrum salicaria

Purple loosestrife is a perennial, emergent aquatic Purple loosestrife is a perennial, emergent aquatic plant. As many as 30 -50 herbaceous, erect, annual plant. As many as 30 -50 herbaceous, erect, annual stems rise to about nine feet tall from a persistent stems rise to about nine feet tall from a persistent perennial tap root and spreading rootstock. The perennial tap root and spreading rootstock. The showy, magenta flowering stems end in a 4-16 inch showy, magenta flowering stems end in a 4-16 inch flowering spike. Purple loosestrife is invasive and flowering spike. Purple loosestrife is invasive and competitive and unavailing to native wildlife. It can competitive and unavailing to native wildlife. It can quickly adapt to environmental changes and expand quickly adapt to environmental changes and expand its range to replace native plantsits range to replace native plants55..


Distribution:

Throughout North America and areas

Worldwide(5)

Sedges – Sedges – Carex spp.Carex spp.

There are many types of sedges (over There are many types of sedges (over 100) and they are difficult to identify 100) and they are difficult to identify without using detailed botanical keys. without using detailed botanical keys. In general, sedges are perennial plants In general, sedges are perennial plants that resemble grasses, grow in shallow that resemble grasses, grow in shallow water or moist soils, and can reach 4 water or moist soils, and can reach 4 feet in height. Sedges often grow in feet in height. Sedges often grow in thick clusters. Stems of sedges are thick clusters. Stems of sedges are usually triangular. Spikes occur on the usually triangular. Spikes occur on the upper sections of the plant and can be upper sections of the plant and can be single or in groupssingle or in groups11. .


Distribution:

Worldwide

(1)

Smartweed – Smartweed – Polygonium spp.Polygonium spp.

Smartweed is a perennial plant Smartweed is a perennial plant that forms dense colonies in that forms dense colonies in shallow water or moist soils and shallow water or moist soils and can grow to 3 feet tall. Stems are can grow to 3 feet tall. Stems are jointed or have swollen leaf nodes jointed or have swollen leaf nodes that are surrounded by a tubular that are surrounded by a tubular sheath. Leaves are alternate, sheath. Leaves are alternate, lance-shaped up to 4 inches long lance-shaped up to 4 inches long but usually less than 1/2 inch but usually less than 1/2 inch wide. Flowers are on spikes at the wide. Flowers are on spikes at the end of stems (often numerous end of stems (often numerous spikes on the same plant). spikes on the same plant). Flowers begin as greenish then Flowers begin as greenish then turn whitish or a light pink in color turn whitish or a light pink in color as they mature. Fruits are flat, as they mature. Fruits are flat, triangular (1/8 inch), dark brown to triangular (1/8 inch), dark brown to blackblack11. .


Distribution:

Nearly Worldwide

(10)

Water Plantain – Water Plantain – Alisma spp.Alisma spp.

These perennial plants typically grow on wet soil or in These perennial plants typically grow on wet soil or in shallow water. Look for parallel veined leaves rising from shallow water. Look for parallel veined leaves rising from the plant base. The small white or occasionally pink the plant base. The small white or occasionally pink flowers occur on delicate stalks arranged in whorls flowers occur on delicate stalks arranged in whorls around the main flower stalk. Stiff leaves generally stand around the main flower stalk. Stiff leaves generally stand above the water surface, but young plants often have above the water surface, but young plants often have ribbon-like underwater leaves. What appear to be stems ribbon-like underwater leaves. What appear to be stems are actually long leaf stalks. The stem is a bulb-like, are actually long leaf stalks. The stem is a bulb-like, usually buried in sediment. White to pinkish individual usually buried in sediment. White to pinkish individual flowers to 7 mm across. They occur in whorls on slender flowers to 7 mm across. They occur in whorls on slender branches arranged around a central flower-stalkbranches arranged around a central flower-stalk1111. .

Copyright property of the Conservation Commission of the

State of Missouri (11)

(11)(11)Photograph by Clayton Antieau

Distribution:

Nearly worldwide


Water Stargrass – Water Stargrass – Heterantheria dubiaHeterantheria dubia

Water Stargrass is grass-like with thin Water Stargrass is grass-like with thin branching dark-green stems and alternate branching dark-green stems and alternate leaves with no prominent midvein. Water leaves with no prominent midvein. Water Stargrass can grow up to 6 feet long and Stargrass can grow up to 6 feet long and can form floating colonies. Flowers rise can form floating colonies. Flowers rise above the surface and are bright yellow, above the surface and are bright yellow, star-shaped, with 6 narrow petals. Water star-shaped, with 6 narrow petals. Water Stargrass reproduces from seeds and Stargrass reproduces from seeds and through fragmentationthrough fragmentation11. .


Distribution:

Throughout most of North

America

(1)

(1)

White Water Buttercup – White Water Buttercup – Ranunculus AquatilisRanunculus Aquatilis

White water buttercup is an White water buttercup is an aquatic, perennial wildflower with aquatic, perennial wildflower with submerged stems measuring from submerged stems measuring from 10-100 cm long. The leaves 10-100 cm long. The leaves alternate along the stems, the alternate along the stems, the submerge leaves dissected into submerge leaves dissected into many needle-like segments. The many needle-like segments. The lower leaves are typically sessile lower leaves are typically sessile while the upper leaves may have while the upper leaves may have petioles measuring up to 2 cm long. petioles measuring up to 2 cm long. The floating leaves are similar to The floating leaves are similar to the lower leaves but are 5-15 mm the lower leaves but are 5-15 mm long and nearly twice as wide, the long and nearly twice as wide, the blades shallowly to deeply 3-lobed blades shallowly to deeply 3-lobed and with toothed or lobed and with toothed or lobed segmentssegments1212. . Distribution:

Throughout most of North America

(12)


Other Online Aquatic Plant ID GuidesOther Online Aquatic Plant ID Guides

Virginia Tech Weed Guide: Virginia Tech Weed Guide: www.ppws.vt.edu/scott/weed_id/aquatics.htmwww.ppws.vt.edu/scott/weed_id/aquatics.htm

University of Florida Invasive Aquatic Plant ID Guide: University of Florida Invasive Aquatic Plant ID Guide: http://aquat1.ifas.ufl.edu/photocat.htmlhttp://aquat1.ifas.ufl.edu/photocat.html

Washington State Department of Ecology – Plant ID Manual Online: Washington State Department of Ecology – Plant ID Manual Online: www.ecy.wa.gov/programs/wq/plants/plantid2/categories.htmlwww.ecy.wa.gov/programs/wq/plants/plantid2/categories.html

Texas Agricultural Extension Service – Aquaplant ID: Texas Agricultural Extension Service – Aquaplant ID: http://aquaplant.tamu.edu/Plant_Id.htmhttp://aquaplant.tamu.edu/Plant_Id.htm

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Information and Image SourcesInformation and Image Sources11Texas Cooperative Extension: Texas Cooperative Extension: http://aquaplant.tamu.edu/Floating%20Plants/Floating_Plant_Index.htmhttp://aquaplant.tamu.edu/Floating%20Plants/Floating_Plant_Index.htm, Texas A & M University, Plant , Texas A & M University, Plant

Identification, 2004Identification, 2004

22Non-Native Invasive Aquatic Plants in the United States: Non-Native Invasive Aquatic Plants in the United States: http://aquat1.ifas.ufl.edu/seagrant/myrspi.jpghttp://aquat1.ifas.ufl.edu/seagrant/myrspi.jpg, Center for Aquatic and Invasive Plants, , Center for Aquatic and Invasive Plants, University of Florida, 2001University of Florida, 2001

33Simmons, Kent. Eurasian Water Milfoil: Simmons, Kent. Eurasian Water Milfoil: http://io.uwinnipeg.ca/~simmons/ysesp/exotic4.htmhttp://io.uwinnipeg.ca/~simmons/ysesp/exotic4.htm, University of Winnipeg, 2004, University of Winnipeg, 2004

44Virginia Cooperative Extension. Aquatic Weeds: Virginia Cooperative Extension. Aquatic Weeds: www.ppws.vt.edu/scott/weed_id/aquatics.htmwww.ppws.vt.edu/scott/weed_id/aquatics.htm, Virginia Tech, 2004, Virginia Tech, 2004

55Problem Aquatic Plants: Problem Aquatic Plants: www.wapms.og/plants/index.htmlwww.wapms.og/plants/index.html, Western Aquatic Plant Management Society , 2004, Western Aquatic Plant Management Society , 2004

66Egmond, Wim Van. Algae:Egmond, Wim Van. Algae:http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/, On-view.net Ltd., Microscopy , On-view.net Ltd., Microscopy UK, 1995UK, 1995

77Parmentier, Jan. Asterionella: Parmentier, Jan. Asterionella: http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/, On-view.net Ltd., , On-view.net Ltd., Microscopy UK, 1995Microscopy UK, 1995

88Morgan, Mike. Some Observations on a Freshwater Algae: Morgan, Mike. Some Observations on a Freshwater Algae: http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/, On-view.net Ltd., Microscopy UK, 2000, On-view.net Ltd., Microscopy UK, 2000

99MSU Extension Bulletin. Aquatic Plant Identification and Management: MSU Extension Bulletin. Aquatic Plant Identification and Management: http://www.pested.msu.edu/BullSlideNews/bulletins/pdf/2437/E-2437_Chap5.pdfhttp://www.pested.msu.edu/BullSlideNews/bulletins/pdf/2437/E-2437_Chap5.pdf, Michigan State University, 2004, Michigan State University, 2004

1010Aquatic and Wetland Plant and Invasive Plants: Aquatic and Wetland Plant and Invasive Plants: http://aquat1.ifas.ufl.edu/photocat.htmlhttp://aquat1.ifas.ufl.edu/photocat.html, Center for Aquatic and Invasive Plants, University of , Center for Aquatic and Invasive Plants, University of Florida, 2001-2002Florida, 2001-2002

1111Aquatic Plant Identification Manual for Washingtons Freshwater Plants: Aquatic Plant Identification Manual for Washingtons Freshwater Plants: http://www.ecy.wa.gov/programs/wq/plants/plantid2/categories.htmlhttp://www.ecy.wa.gov/programs/wq/plants/plantid2/categories.html, , Washington State Department of Ecology * distribution info found hereWashington State Department of Ecology * distribution info found here

1212Wright, John. Wildflowers of Ontario – White Water Buttercup: Wright, John. Wildflowers of Ontario – White Water Buttercup: www.wildflowers.reach.netwww.wildflowers.reach.net, 2001., 2001.

1313Mehrhoff, Lesli, J. Invasive Plant Atlas of New England Mehrhoff, Lesli, J. Invasive Plant Atlas of New England http://webapps.lib.uconn.edu/ipane/jpg/images.cfm?unique_identifier=uconn_ipane_cabomcarol_02http://webapps.lib.uconn.edu/ipane/jpg/images.cfm?unique_identifier=uconn_ipane_cabomcarol_02, 2003, 2003

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Some Common Algae and Aquatic Weeds of Canada and U.S. Basic Identification and Information Guide Revision Date: November 1, 2004 START MENU